DuPuis Family Cobra Build

Remember this thread? https://www.pilotsofamerica.com/community/threads/cheap-kit-car.112444/

It's better to spend the money and get something you like.

I do remember, and I agree overall. That said I also think the exocet would’ve been a ton of fun and I would’ve enjoyed it. However given my luck with parts cars I would’ve been in it for closer to $20k by the time I messed around with the engine and transmission to my liking, and at that point I would’ve been better off doing the factory five like I did.

So ultimately I’m happy I went with the Cobra by a long shot, and my wife will like it a lot more which is also good. We’ll see if I regret the solid rear axle once I start driving it, and if I decide I want a 302/T-5 I can always build some of those up and swap in at a later point.

Really though, I’m pretty certain that I’ll be very happy with it and then I’ll move on to building an XJ13 or GT40.
 
That kitty cat did NOT look happy, Ted.

The kittens have jobs to do - take care of the mice. Of course they aren’t happy, they’re at work. ;)
 
Ya know, your kids are going to think you are the smartest person in the world for building a car.

At least until they are teenagers....:lol::lol:
 
Ya know, your kids are going to think you are the smartest person in the world for building a car.

At least until they are teenagers....:lol::lol:

Oh don't worry, I already get the "Dad you're such an idiot" from my son. Kid's too smart to think I'm smart. ;)
 
Here's an overdue video from last weekend that I shot, just uploaded:


A few minor updates, specifically I sealed and torqued down the timing cover and water pump. Progress!

The main thing I'm thinking about and figuring on is what to do regarding the intake studs. If you look in the video you'll see what I'm talking about, but on the center 4 studs on each side there's not too much thread sticking up. There's certainly not good space for a washer in there (well, by "good" I mean "any"). So I could put the nuts on without washers, or get some flange nuts. Curious what others would think make sense there. I could also unscrew the studs from the head a turn or so to get more room, but I'm not sure how I feel about that.

I think the next thing I'm going to work on while I consider what to do with the intake will be the radiator. Well, and finish up the fuel lines, but I still need to order those adapters to finish that up. I'm in a spot where I can install the radiator, though, so I may as well do that and throw out the box. I'm flying dogs today and tomorrow so I probably won't do anything on that this weekend.
 
Here's an overdue video from last weekend that I shot, just uploaded:


A few minor updates, specifically I sealed and torqued down the timing cover and water pump. Progress!

The main thing I'm thinking about and figuring on is what to do regarding the intake studs. If you look in the video you'll see what I'm talking about, but on the center 4 studs on each side there's not too much thread sticking up. There's certainly not good space for a washer in there (well, by "good" I mean "any"). So I could put the nuts on without washers, or get some flange nuts. Curious what others would think make sense there. I could also unscrew the studs from the head a turn or so to get more room, but I'm not sure how I feel about that.

I think the next thing I'm going to work on while I consider what to do with the intake will be the radiator. Well, and finish up the fuel lines, but I still need to order those adapters to finish that up. I'm in a spot where I can install the radiator, though, so I may as well do that and throw out the box. I'm flying dogs today and tomorrow so I probably won't do anything on that this weekend.

They really didn't give you a good option on those two nuts in the center. Are you sure you can't slide a bolt in there? It looks like the holes in the manifold are a good bit larger than the bolt thread. Maybe if you tried sliding the bolts in with the manifold off the engine it would work. If that won't work, I'd go ahead and back them out a couple of more threads. Given the choice between tightening a steel nut directly against cast aluminum and backing the stud out a few threads, I'd go for backing out the studs. With manifold bolts I'm guessing you're looking at 25 - 30 foot pounds, and a couple threads less shouldn't be an issue.

Sure would have been nice if they had machined a relief for those two studs like they did for the others, but that would require some sort of an odd two piece cutting tool.
 
They really didn't give you a good option on those two nuts in the center. Are you sure you can't slide a bolt in there? It looks like the holes in the manifold are a good bit larger than the bolt thread. Maybe if you tried sliding the bolts in with the manifold off the engine it would work. If that won't work, I'd go ahead and back them out a couple of more threads. Given the choice between tightening a steel nut directly against cast aluminum and backing the stud out a few threads, I'd go for backing out the studs. With manifold bolts I'm guessing you're looking at 25 - 30 foot pounds, and a couple threads less shouldn't be an issue.

Sure would have been nice if they had machined a relief for those two studs like they did for the others, but that would require some sort of an odd two piece cutting tool.

I tend to agree with you that a thread or two out of the studs would be fine, and then maybe just take a dremel to that top part of the studs which has no thread on it. Would probably get me what I need and so it's probably what I'll do.

I understand why they made it the way they did, and to some extent appreciate it. The intake has a straight shot, and an equal straight shot, for each of the 8 throttle bodies into its cylinder. But I do feel like they could've put a bit more thought and R&D into it and come up with a better solution. Then again, as I said in the video, it's cheap, so you get what you pay for. Quality wise they seem to have gotten it where it counts.
 
Today I ran by the hardware store and spent some time on Summit Racing to get some of what I needed.

I bought the shorter bolt I needed for that rearmost position on the intake manifold. I would've liked a bolt that used an allen head instead of a standard hex head, but all they had was hex head. That's fine, it'll work. It's the right length at 1/2" shorter than what I had, and should work fine.

I then got some 6-point nuts for those center studs on the intake manifold, which will also work. I'll cut off the non-threaded tops of the studs and then put it all together. The 6-point nuts are also a bit shorter than the 12-point nuts that ARP included, which I think is a benefit in this case. It won't win any shows since there will be 3 different types of fasteners, but it will have what it needs to work. Good enough for me, I'm happy. I also got a piece of aluminum that I think would be better than the one I bought before for making the fuel rail brackets.

Summit, I had to order a bunch of different fittings to finish up the fuel lines. I think I've ordered what I need to make it work at this point, and so everything will be either inverted flare or -6 AN rather than some sort of compression fitting or hoses with barbed fittings, which I would rather avoid in this case. Again, trying to get all the same color wasn't going to happen but it'll work fine. Once the box from Summit arrives (should ship today they said, so probably Wednesday or Thursday) I'll be able to finish up the fuel lines, and then at that point start riveting on those rear aluminum panels.

Laurie heads to work tomorrow so my hoped for agenda for this week will be:

- Torque down the intake and call that job "done" (although I still need a thermostat housing)
- Finish up the fuel lines
- Install the oil pan
- Make the brackets for the fuel rails and install those
- Install the radiator

I don't really need to install the radiator at this point, but I'm getting close to the point where it does need to happen and it would let me get rid of another box. Throwing out boxes = progress!
 
I'm thinking about which sort of harmonic balancer I want to go with. Being a 28 oz external balance engine, I do need to have a proper harmonic balancer.

To get a good harmonic balancer is something in the $300-400 range. But those are also in the range of 12-15 lbs of rotating mass, which of course I'm trying to minimize as much as possible. Since I'm going to go with EDIS ignition I also need something that has the trigger wheel, like this:


102140.jpg


The 5.0 Explorers (which used this system) were 50 oz external balance not 28 oz. So I can't just put on an Explorer balancer. This gets me in the realm of needing something custom. Since I'm looking for super lightweight, that's gotten me looking at these guys:

https://innovatorswest.com/

They offer a bunch of lightweight balancers, even as low as about 5 lbs. Significant weight savings which translates into more responsive, which is the whole point. Cost is a bit higher than a heavier good quality balancer, but I think I may give them a call and see what they'd quote me to put something together.

I confirmed the hardware I bought will work on the intake manifold. So, getting close to putting that thing on...
 
The balancer issue seems to be the next one on my list of things requiring substantial thought.

I called Innovators West the other day and then had a few email exchanges. They aren't able to provide a balancer that meets my needs for EDIS. They, or at least have claimed that so far. I may try some additional communications with them. See below for a view of the back of the damper:

20191107_111845.jpg

The counterweight on the back (remember this is an externally balanced engine) they confirmed is steel. I could attach a trigger wheel to that, although the hard part/question might be doing so in a way that would remain stable and attached around the entire circumference of the damper.

Although I want to minimize weight, this is also making me think maybe I should just give up on this aluminum damper idea and go with a normal steel one, accepting the weight penalty. I'm looking at ATI and Romac options as well and am going to look for some tech support ideas from them.

I could alternately ditch the EDIS idea entirely and instead go with a normal distributor, but I don't really want to do that. I like having the total control with a computer given the direction the car has taken, even if it adds some effort to get there.

So far I haven't done anything on the car this week while Laurie's been at work. It's just been a busy week and I've been too tired in the evenings to do much, but hopefully this weekend I'll get some things done.
 
The balancer issue seems to be the next one on my list of things requiring substantial thought.

I called Innovators West the other day and then had a few email exchanges. They aren't able to provide a balancer that meets my needs for EDIS. They, or at least have claimed that so far. I may try some additional communications with them. See below for a view of the back of the damper:

View attachment 79531

The counterweight on the back (remember this is an externally balanced engine) they confirmed is steel. I could attach a trigger wheel to that, although the hard part/question might be doing so in a way that would remain stable and attached around the entire circumference of the damper.

Although I want to minimize weight, this is also making me think maybe I should just give up on this aluminum damper idea and go with a normal steel one, accepting the weight penalty. I'm looking at ATI and Romac options as well and am going to look for some tech support ideas from them.

I could alternately ditch the EDIS idea entirely and instead go with a normal distributor, but I don't really want to do that. I like having the total control with a computer given the direction the car has taken, even if it adds some effort to get there.

So far I haven't done anything on the car this week while Laurie's been at work. It's just been a busy week and I've been too tired in the evenings to do much, but hopefully this weekend I'll get some things done.

If you can get an off the shelf piece I'd do that, even if there is a weight penalty. You're not building a race car, plus if the balancer and trigger wheel come from together, the pieces could do a lot of damage.

Besides, you're going to be busy with your new VTOL aircraft, and this will save some time.
 
If you can get an off the shelf piece I'd do that, even if there is a weight penalty. You're not building a race car, plus if the balancer and trigger wheel come from together, the pieces could do a lot of damage.

Besides, you're going to be busy with your new VTOL aircraft, and this will save some time.

I would definitely accept the weight penalty if there was an off-the-shelf option. However, I have not been able to find one. The Explorer's balancer would be off the shelf (I think) but it's a 50 oz external balance and I need 28. Putting the wrong balancer on would not work out well at all.
 
I'd work hard to find a solution that allows for EDIS. Once I got mine dialed in on a dyno, it made for good around town driveability and great response when I laid into the happy pedal.
 
I'd work hard to find a solution that allows for EDIS. Once I got mine dialed in on a dyno, it made for good around town driveability and great response when I laid into the happy pedal.

That's my thought as well. The other thing is that I realistically don't need that damper until it's time to start the engine so I do have time to work on it while I work on all the other things (including the electrical, which is a bigger deal).
 
Well, this was a very productive weekend, the most productive weekend I've had on the Cobra in a while.

The intake manifold is officially on and torqued down. I'm not entirely thrilled with how it all went together, but I think it should seal just fine. I ended up cutting the tops off of the inner 4 studs with the dremel and then unscrewing them from the head bout a turn. Torqued in the appropriate pattern. It doesn't look especially pretty because of the mismatched fasteners at different heights, but really a lot of that has to do with the intake itself. They could have designed it to be easier to install, but they didn't.

I then went and made the longer brackets that I thought I needed for the fuel rails using Ford injectors. Not particularly hard but took about an hour. When I went to get the hardware out of the bag, I realized that the intake had come with two sets of brackets and, you guessed it, one was longer and fit Ford style injectors. I had to laugh at that and give myself the idiot of the day award. One of the brackets touched the throttle body it was attached to, so I had to trim it down again. Machining on this intake definitely leaves something to be desired.

But, the fuel rails and injectors are on, and the intake is in. I then did some looking at it to figure out how I want to run the fuel system. I need to buy a different fitting for the aft of the passenger side fuel rail, specifically a 90-degree fitting. I did some thinking about how I wanted to route everything, and decided that the rear will be the crossover, and then the front ports will be the inlet and outlet. I'll need to do some more thinking to figure out exactly how I want to plumb all of that and where to mount the fuel pressure regulator. There are a few areas that look promising but I also need to make sure they'll have adequate clearance for the body.

I also got the fuel lines effectively done. There's a little more clean-up to do in the back where I have the fuel filter mounted (or rather where it needs to be mounted - right now just sitting) , but I'm happy with how the lines are routed and they're attached mostly. Fittings need to all get tightened, and then I need to bend the lines up front in the engine bay.

I was going to put the starter on, but decided that I was going to get a new one after all. This one works but with the oil pan I'm using, replacing it is a pain. Some have said you have to remove the oil pan to get the starter off. I'm skeptical of that, but it would be a pain since the race pan goes underneath the starter. And then after my issue with my tube of Right Stuff, I couldn't put the oil pan on anyway. So those items got taken off the list.

I then looked at the radiator, and ultimately decided I don't want to put that on until I'm fairly close to being ready for first start. As much as I'd like to "close up" each system one at a time, the radiator is going to ultimately be very in the way, and until the body gets put on the bottom portion of it is held in place by zip ties. Those two things strike me as just asking for trouble. So I think what I want to do is get the car otherwise ready to run, install the radiator last, then fill the system with coolant and do the first start and go-karting, before putting the body on.

Today I then went ahead and riveted on one of the trunk panels, specifically the upper on. There were a couple of lines of holes I hadn't drilled, so I had to get my 1/8" drill bit out and do those. Didn't take long and then got those siliconed on. Factory Five includes both 1/4" and 1/2" length rivets, and I apparently have used some 1/2" ones in places they didn't need to be (and/or drilled too many holes... probably a bit of both) and I will need to buy more. I had just enough for this panel.

I then figured I'd keep on going with progress and rivet on the lower trunk panel. However, first I need to trim it. There are some triangular panels on the sides of the inner trunk that I thought could go on first. Well, apparently I was wrong and the lower trunk aluminum panel is now just a hair too wide to fit. Oops. Not a hard fix, just have to grind some material away. But I wasn't going to do that today.

I also started playing around with the throttle cable some. I'm going to have to make a bracket on the intake for it, but I got it mounted to the body. The gas pedal I got I'm also going to need to do a bit of adjustment on to make the cable fit on it correctly.

One thing that I started working on but am thinking about how I want to handle is the hand brake cables. Factory Five has you run the Mustang cables underneath one of the 4" round tubes. In other words, every time you pull on the hand brake lever it literally will be rubbing the cables on the tube. Realistically for how much (little) the hand brake is used, this is unlikely to cause a problem. However I inherently don't like the idea of running something such that it, by design, touches something else.

So, good progress. Several boxes thrown out, some big parts finished. I'm guessing that the fuel system is going to require two more orders from Summit to get everything that I need to finish it up although I may get away with one. The gas pedal is close to doing what it's supposed to, at which point all three pedals will be physically doing what they're supposed to.

I want to finish up the fuel system components and the throttle cable (including bracket), and of course install the starter and oil pan. But after that, I think the next step will be electrical. Maybe working on the HVAC first or in parallel to some extent.

But, this makes me smile:

77228727_964451639313_1169721363674431488_n.jpg
 
Well, this was a very productive weekend, the most productive weekend I've had on the Cobra in a while.

The intake manifold is officially on and torqued down. I'm not entirely thrilled with how it all went together, but I think it should seal just fine. I ended up cutting the tops off of the inner 4 studs with the dremel and then unscrewing them from the head bout a turn. Torqued in the appropriate pattern. It doesn't look especially pretty because of the mismatched fasteners at different heights, but really a lot of that has to do with the intake itself. They could have designed it to be easier to install, but they didn't.

I then went and made the longer brackets that I thought I needed for the fuel rails using Ford injectors. Not particularly hard but took about an hour. When I went to get the hardware out of the bag, I realized that the intake had come with two sets of brackets and, you guessed it, one was longer and fit Ford style injectors. I had to laugh at that and give myself the idiot of the day award. One of the brackets touched the throttle body it was attached to, so I had to trim it down again. Machining on this intake definitely leaves something to be desired.

But, the fuel rails and injectors are on, and the intake is in. I then did some looking at it to figure out how I want to run the fuel system. I need to buy a different fitting for the aft of the passenger side fuel rail, specifically a 90-degree fitting. I did some thinking about how I wanted to route everything, and decided that the rear will be the crossover, and then the front ports will be the inlet and outlet. I'll need to do some more thinking to figure out exactly how I want to plumb all of that and where to mount the fuel pressure regulator. There are a few areas that look promising but I also need to make sure they'll have adequate clearance for the body.

I also got the fuel lines effectively done. There's a little more clean-up to do in the back where I have the fuel filter mounted (or rather where it needs to be mounted - right now just sitting) , but I'm happy with how the lines are routed and they're attached mostly. Fittings need to all get tightened, and then I need to bend the lines up front in the engine bay.

I was going to put the starter on, but decided that I was going to get a new one after all. This one works but with the oil pan I'm using, replacing it is a pain. Some have said you have to remove the oil pan to get the starter off. I'm skeptical of that, but it would be a pain since the race pan goes underneath the starter. And then after my issue with my tube of Right Stuff, I couldn't put the oil pan on anyway. So those items got taken off the list.

I then looked at the radiator, and ultimately decided I don't want to put that on until I'm fairly close to being ready for first start. As much as I'd like to "close up" each system one at a time, the radiator is going to ultimately be very in the way, and until the body gets put on the bottom portion of it is held in place by zip ties. Those two things strike me as just asking for trouble. So I think what I want to do is get the car otherwise ready to run, install the radiator last, then fill the system with coolant and do the first start and go-karting, before putting the body on.

Today I then went ahead and riveted on one of the trunk panels, specifically the upper on. There were a couple of lines of holes I hadn't drilled, so I had to get my 1/8" drill bit out and do those. Didn't take long and then got those siliconed on. Factory Five includes both 1/4" and 1/2" length rivets, and I apparently have used some 1/2" ones in places they didn't need to be (and/or drilled too many holes... probably a bit of both) and I will need to buy more. I had just enough for this panel.

I then figured I'd keep on going with progress and rivet on the lower trunk panel. However, first I need to trim it. There are some triangular panels on the sides of the inner trunk that I thought could go on first. Well, apparently I was wrong and the lower trunk aluminum panel is now just a hair too wide to fit. Oops. Not a hard fix, just have to grind some material away. But I wasn't going to do that today.

I also started playing around with the throttle cable some. I'm going to have to make a bracket on the intake for it, but I got it mounted to the body. The gas pedal I got I'm also going to need to do a bit of adjustment on to make the cable fit on it correctly.

One thing that I started working on but am thinking about how I want to handle is the hand brake cables. Factory Five has you run the Mustang cables underneath one of the 4" round tubes. In other words, every time you pull on the hand brake lever it literally will be rubbing the cables on the tube. Realistically for how much (little) the hand brake is used, this is unlikely to cause a problem. However I inherently don't like the idea of running something such that it, by design, touches something else.

So, good progress. Several boxes thrown out, some big parts finished. I'm guessing that the fuel system is going to require two more orders from Summit to get everything that I need to finish it up although I may get away with one. The gas pedal is close to doing what it's supposed to, at which point all three pedals will be physically doing what they're supposed to.

I want to finish up the fuel system components and the throttle cable (including bracket), and of course install the starter and oil pan. But after that, I think the next step will be electrical. Maybe working on the HVAC first or in parallel to some extent.

But, this makes me smile:

77228727_964451639313_1169721363674431488_n.jpg


That was a lot of progress for the weekend, and you have a pretty picture to show for it.
 
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That was a lot of progress for the weekend, and you have a pretty picture to show for it.

Yeah, I was really pleased with how much I got done. I've always said that every time I work on this car I feel like I've made positive progress, but this was really productive, especially after how slow things have been the past few weeks. It's nice to be so close to starting electrical.
 
Nice progress, Ted. I admire your ability to visualize and press on; not certain how well I could do Thant!

Question: you reference an electric AC unit above. Details? I’m curious.
 
Man, I want a copy of that engine, it just looks cool.
 
Excellent. Just in time to reward yourself with a premiere showing of a certain Matt Damon/Christian Bale movie. ;)

Yes! Unfortunately I won't be able to drive the car to it as I'd hoped. However, the Cobra Club president also flaked out on his original suggestion of a group drive to see it. My wife and I are going to make a date night/night without the kids of it, so we'd be driving a more practical car anyway (maybe we'll take the XKR). So not a big deal.

Nice progress, Ted. I admire your ability to visualize and press on; not certain how well I could do Thant!

Question: you reference an electric AC unit above. Details? I’m curious.

My plan is to get one of the Masterflux compressors that you first introduced me to some years back. Their smallest one is the right size for the Cobra, and that will allow me to do a few things. 1) Play with it (I've been looking for a project to do this on for a while) 2) Mount the compressor in the trunk, which helps with weight distribution 3) Let me stick to the alternator being the only thing I drive off of the engine.

The visualizing the end goal and working with the engineering design decisions is part of the fun for me. :)

Man, I want a copy of that engine, it just looks cool.

Thanks. :) The Edelbrock valve covers are growing on me, but they're still going to get replaced with something else. In fact I think I'm going to order the new ones (whatever they are) and put them on sooner rather than later.

It should come as no surprise that I'm already thinking of what I might do for a more unique/custom engine for this car (if I decided . One of my friends is a strong student of engine design, even moreso than me to a large extent, and we've been talking about what would be a "better design" engine. For a number of reasons I don't see myself changing the drivetrain on this car, but as I said a number of pages ago there were some decisions on the drivetrain I made that were cost-driven (and ease of acquisition driven) at least to some extent. The thoughts could play into what I might do on a future build or what I might do if for some reason I decided that I should do something different with this car or apply the ideas to a future build on a different vehicle.

A couple of things I've thought about include a de-stroked, flat-plane crankshaft based on a 351W block (but displacing something more in the 302-327 range) with an aluminum block, designed for high revs, like in the 9,000 RPM range. I'd thought about this before and it would be a lot of fun. This would also better lend itself to a built up T5 vs. the TKO for a few reasons, and would shave around 100 lbs out of the drivetrain while making something really fun.

Reality is I'll drive the car and enjoy it just the way it is, then I'll want to start working on the XJ13.
 
So now I'm thinking about fuel pressure regulators, and what to do about them.

The fuel rails aren't designed for a fuel pressure regulator built-in, but all sorts of things can happen with fittings. I could try to mount a pressure regulator on the fuel rail, or I could mount it elsewhere in the engine bay. I need to look at it some more, but I probably am better off just mounting the fuel pressure regulator elsewhere and then running the fuel lines.

I'm also looking at different pressure regulators. There's the Summit Racing brand for around $100, Holley makes one for around $65, and Aeromotive for about $145. I suspect any of them would be fine. But I need to do some thinking before putting together another order with Summit.
 
I did some more looking at the car last night. I'm at a phase now where piddling on it for a little bit each evening is less appealing to me. Although I have some tasks that could theoretically get done within that time period, I'm more at the point where I just want to be able to spend the better part of a Saturday (or at least a few hours in a stretch) working on it.

I'm still not sure where I want to mount the fuel pressure regulator. I think my real answer is that I want to mount it to the fuel rail and doing so would make the most sense, although I'm not sure about the weight there as well as making sure it's clocked properly may make that not feasible.

This requires more thinking.

I also am thinking some more regarding the trigger wheel. I think one of these could be quite thin, and if anything bolting it to aluminum could be beneficial since then there wouldn't be interference from a steel trigger ring. I need to do some more measurements and figure this out, but I think it should be doable. This is getting me back on the Innovators West idea. Lighter weight plus aluminum for the main housing. I do need to do some more measuring, though, and really I also need to get a VR sensor to install to help with some of these measurements to make sure that I get this figured out correctly.

Over the weekend I recorded a video, but I didn't like how it turned out. So I did a "take 2" (even though all my videos are 1-takes) last night and uploaded it today.


Laurie and I are going to see Ford v. Ferrari on Friday. The Cobra won't be driving, obviously, but it's cold enough that we wouldn't want to take it anyway. We'll take the XKR probably.
 
The Romec tech folks got back and have a 7 lb balancer with 28 oz external balance, and the price is less than ATI or Innovators West. Probably more of a balancer. Now that has my attention. I asked for some pictures so I could see what it looked like. I need to look into it some more, but that might be getting me more of what I want. I'm sure it's not SFI approved but a lot of what I'm doing on this engine doesn't meet SFI standards so that by itself isn't too big of a deal.

I made a post on the Factory Five group asking for suggestions of places to mount the fuel pressure regulator. Several people have done the firewall mount, and then I got some responses saying "that's not safe!" and also pointing out how any fuel pressure gauge should have an isolator so fuel can't get into the cabin. Part of me laughs at that given that just about every fuel injected plane (at least the ones I've flown) runs a line with 100LL into the cabin for the fuel flow/fuel pressure gauge. So I'm less worried about a gasoline line in a car. I'm also not entirely sure about having a fuel pressure gauge in the car.
 
The Romec tech folks got back and have a 7 lb balancer with 28 oz external balance, and the price is less than ATI or Innovators West. Probably more of a balancer. Now that has my attention. I asked for some pictures so I could see what it looked like. I need to look into it some more, but that might be getting me more of what I want. I'm sure it's not SFI approved but a lot of what I'm doing on this engine doesn't meet SFI standards so that by itself isn't too big of a deal.

I made a post on the Factory Five group asking for suggestions of places to mount the fuel pressure regulator. Several people have done the firewall mount, and then I got some responses saying "that's not safe!" and also pointing out how any fuel pressure gauge should have an isolator so fuel can't get into the cabin. Part of me laughs at that given that just about every fuel injected plane (at least the ones I've flown) runs a line with 100LL into the cabin for the fuel flow/fuel pressure gauge. So I'm less worried about a gasoline line in a car. I'm also not entirely sure about having a fuel pressure gauge in the car.

Some of our race cars had fuel pressure gauges, most did not. It's not like an airplane with multiple tanks where a flickering fuel pressure gauge indicates you're about to run one dry and it's time to switch, or you want to see some positive indication that the boost pump is working. If I were building a race car today I wouldn't install one, I don't recall getting much useful information out of them.
 
Some of our race cars had fuel pressure gauges, most did not. It's not like an airplane with multiple tanks where a flickering fuel pressure gauge indicates you're about to run one dry and it's time to switch, or you want to see some positive indication that the boost pump is working. If I were building a race car today I wouldn't install one, I don't recall getting much useful information out of them.

When I was a mechanic it was often useful as a diagnostic tool when something went wrong. And since often the conditions were when running, a fuel pressure gauge on the rail itself wouldn't be particularly useful and so we normally had a pressure gauge hanging out from under the hood and clamped under the windshield wipers. So the mechanic in me says that would be useful to have in the car.

I still haven't decided for sure what I'm going to be doing for gauges and haven't ordered them. I imagine that there will be some Black Friday/Cyber Monday deals going on so that would probably be a good time for me to try to order the bulk of the remaining expensive components (like those).
 
I had a fuel pressure gauge on the fuel rail in my Megasquirt 911. Only used it to adjust the regulator and check pressure when the engine was running. Not sure what I would have done with it visible from the passenger compartment
 
I had a fuel pressure gauge on the fuel rail in my Megasquirt 911. Only used it to adjust the regulator and check pressure when the engine was running. Not sure what I would have done with it visible from the passenger compartment

When you have fuel problems the pressure gauge can help you understand whether that problem is in the pump, regulator, or something electronic/computerized based on the behavior while driving, especially under load. A weak fuel pump can make pressure at idle and then go down to around 0 once under load.
 
The Romec tech folks got back and have a 7 lb balancer with 28 oz external balance, and the price is less than ATI or Innovators West. Probably more of a balancer. Now that has my attention. I asked for some pictures so I could see what it looked like. I need to look into it some more, but that might be getting me more of what I want. I'm sure it's not SFI approved but a lot of what I'm doing on this engine doesn't meet SFI standards so that by itself isn't too big of a deal.

I made a post on the Factory Five group asking for suggestions of places to mount the fuel pressure regulator. Several people have done the firewall mount, and then I got some responses saying "that's not safe!" and also pointing out how any fuel pressure gauge should have an isolator so fuel can't get into the cabin. Part of me laughs at that given that just about every fuel injected plane (at least the ones I've flown) runs a line with 100LL into the cabin for the fuel flow/fuel pressure gauge. So I'm less worried about a gasoline line in a car. I'm also not entirely sure about having a fuel pressure gauge in the car.
I remember a certain Debonair that had the fuel pressure gauge fill with 100LL

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I get the use of the FP gauge as a potential troubleshooting tool, but how often does that need arise? Once you’ve got the engine sorted out, I doubt you’d have much use for it. I’d rather just plumb in a bung you could attach one temporarily if you needed to diagnose an issue, or find a techy way to do it with a Bluetooth pressure sensor.
 
I get the use of the FP gauge as a potential troubleshooting tool, but how often does that need arise? Once you’ve got the engine sorted out, I doubt you’d have much use for it. I’d rather just plumb in a bung you could attach one temporarily if you needed to diagnose an issue, or find a techy way to do it with a Bluetooth pressure sensor.

I agree that the need for troubleshooting like that is pretty rare. The fuel pressure regulators I'm looking at all have ports for a gauge built-in to them. I'm looking at this one as an option as well:

https://www.summitracing.com/parts/aei-13130/overview/

Which comes as a complete package, including a gauge. I could leave all of that set up under the hood and then if I had a diagnostic need just put on some fittings with a flexible line to run the gauge to someplace I could fit it. Really, that probably makes more sense.

The way the stock dashboard is set up, you have 5 2 1/16" gauges. The standard ones most people use are oil pressure, oil temp, coolant temp, fuel level, and clock. I'm not going to put in a clock in. I've never run oil temp in a normal car before (my Ram is the first road vehicle I've owned with an oil temp gauge) so I'm somewhat wondering whether I want to run that. My oil pan does have a port for an oil temp probe, so it's possible.

I know I want oil pressure, coolant temp, and fuel level. What I do with the other two, not sure. Having an air/fuel ratio gauge would be more useful, or two given the fact that each bank could be different. Really one would probably be fine. I can also add gauge holes.

But, I think fair points that I don't really need a fuel pressure gauge in the cockpit.
 
I agree that the need for troubleshooting like that is pretty rare. The fuel pressure regulators I'm looking at all have ports for a gauge built-in to them. I'm looking at this one as an option as well:

https://www.summitracing.com/parts/aei-13130/overview/

Which comes as a complete package, including a gauge. I could leave all of that set up under the hood and then if I had a diagnostic need just put on some fittings with a flexible line to run the gauge to someplace I could fit it. Really, that probably makes more sense.

The way the stock dashboard is set up, you have 5 2 1/16" gauges. The standard ones most people use are oil pressure, oil temp, coolant temp, fuel level, and clock. I'm not going to put in a clock in. I've never run oil temp in a normal car before (my Ram is the first road vehicle I've owned with an oil temp gauge) so I'm somewhat wondering whether I want to run that. My oil pan does have a port for an oil temp probe, so it's possible.

I know I want oil pressure, coolant temp, and fuel level. What I do with the other two, not sure. Having an air/fuel ratio gauge would be more useful, or two given the fact that each bank could be different. Really one would probably be fine. I can also add gauge holes.

But, I think fair points that I don't really need a fuel pressure gauge in the cockpit.

No ammeter/voltimeter? Also, most of the AFR gauges are pretty pointless unless you're doing a wideband 02 setup. Most guys that have them with narrow-band and end up with pretty much meaningless data. Even a manifold vacuum gauge might be as useful as a fuel pressure guage for diagnosis.
 
No ammeter/voltimeter? Also, most of the AFR gauges are pretty pointless unless you're doing a wideband 02 setup. Most guys that have them with narrow-band and end up with pretty much meaningless data. Even a manifold vacuum gauge might be as useful as a fuel pressure guage for diagnosis.

I'm planning on WBO2 sensors on the car. Right now I'm planning both banks, although I may downgrade that to one bank, and I could also downgrade it to neither. MegaSquirt has the ability to self-tune with a WBO2 to a "target AFR" you put in.

There's the question about how much I care about that during normal use, but AFR is one of those things that can get too lean and the engine will seem to still run fine but then have detonation. With my estimated 400 HP out of a 351W, the engine will definitely have the ability to detonate.

Voltmeter would be a good standard and might be the more logical thing to go with for the 5-pack. I don't worry about ammeters.
 
I'm planning on WBO2 sensors on the car. Right now I'm planning both banks, although I may downgrade that to one bank, and I could also downgrade it to neither. MegaSquirt has the ability to self-tune with a WBO2 to a "target AFR" you put in.

There's the question about how much I care about that during normal use, but AFR is one of those things that can get too lean and the engine will seem to still run fine but then have detonation. With my estimated 400 HP out of a 351W, the engine will definitely have the ability to detonate.

Voltmeter would be a good standard and might be the more logical thing to go with for the 5-pack. I don't worry about ammeters.

Yeah, I'd go with Voltmeter, too. I have an ammeter in the boat (with single-wire alternator), but that's just how they did it back in 1976. Most people don't like having the power load running up to the dash for an ammeter vs a voltmeter, from a safety standpoint. The AFR is just one of those gauges that tends to swing back and forth a bit depending on operating conditions and such, which often makes it less useful unless fighting a detonation problem or trying to optimize the AFR for a particular operating range (like WOT or cruise RPM). I guess it just depends on if you want you gauge package to be a systems monitor, or a diagnostic/tuning center (not that those are always mutually exclusive).
 
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