DuPuis Family Cobra Build

[SoonerAviator]

I've seen those. Not enough light for me to consider putting them up. I like really, really bright in my garage. That was my favorite feature of the Ohio garage - it was bright enough in there that I rarely needed a shop light at all.

Well, I think they're plenty bright in my garage, but I only have an 8' ceiling and white walls. If you have a taller ceiling and darker walls, their light output would probably start to become a factor. With 6 in my garage, I could work on just about anything exterior or on the top of the engine without needing additional lighting. My fathers shop which is closer to 40x60 w/10' ceiling has 8 4' dual bulb T5 light fixtures and is almost like a surgical room with all of them on.

 

[Ted]

Well, I think they're plenty bright in my garage, but I only have an 8' ceiling and white walls. If you have a taller ceiling and darker walls, their light output would probably start to become a factor. With 6 in my garage, I could work on just about anything exterior or on the top of the engine without needing additional lighting. My fathers shop which is closer to 40x60 w/10' ceiling has 8 4' dual bulb T5 light fixtures and is almost like a surgical room with all of them on.

I have a taller ceiling, it's about 10' total. Then there's the beam that comes down around 18". The ceilings have popcorn on them (which for those who haven't tried hurts lighting quite a bit) and a large percentage of the walls are covered somehow or another. In Ohio the walls were a light to medium grey, so they weren't white. These walls are standard cheap white.

Those LED lights I linked above might be worth trying, though...

 

[Craig]

Watch the color temp on the led's. Most of the big box ones run about 4000K. I run non led's in my garage with a color temp of 6500K. I'm looking to replace them with led's with color temps in the 6000K range.

 

[Ted]

I've been watching those. 5000-6000k is the ideal for me.

 

[Ted]

Revisiting the engine question for the guys who know SBFs, since I quite honestly don't. I know more about oddballs like Jaguar V12s.

Originally I'd decided on a 302-based engine. Bought the donor car that had a 302 which had Edelbrock Performer heads with 2.02/1.60 valves in them. Still plan on using the heads, but the block itself is bored 50 over and has scoring in it, so I started thinking about another path and was thinking about getting a 351W since short blocks for those (freshly rebuilt) can be had pretty cheaply.

However that idea never felt quite right to me. It goes against the concept of "reduce weight and add lightness" which I want to do on this car as much as is practical. Furthermore, it adds 50 lbs of weight right in the front of the engine, and also has a heavier rotating assembly (which is more bad).

I also talked to a friend who built a Mk4. He had a 351W in it and then put in a 408W after he blew up the 351. He said that on paper it sounds great, but the reality is that it's more power on the street than is usable. On his car he's able to break the tires loose in 3rd and 4th gear, which is really not fun. That came around with the 408 more than the 351, but he said if he could do it again he would've done a 302-based block as he thinks the car would've been more balanced that way.

Although it'll cost me more, I'm starting to think that a 331 is the answer, as some people had suggested previously. Gets the weight of the 302 and a lighter weight/more revvy rotating assembly most of the displacement of the 351. Should keep the torque at appropriate levels to still be stupidly fast without breaking tires loose in the upper gears. Reality is that at 2400 lbs, even a stock 302 provides fairly ridiculous power.

Looking around, I can also do a 347 for about the same price as a 331. However my general thought is that the angles and clearances when you get to a 347 end up being somethign I don't want on the street car. Redline will be around 6500 RPM per my goal.

Am I on the right track with these theories? Obviously the cam and other things will determine the total power band, but with the larger 2.02/1.60 valves am I going to have too much airflow for that size engine? While part of me wants to build a 7500 RPM engine my understanding is that stock 302 blocks won't handle that well and will come from together when pushed that high.

 

[SoonerAviator]

I still maintain that you won't be able to feel 50lbs of increased engine weight. Get the 351w short block (or build short block from bare), and grab the Edelbrock Performer heads/intake/carb. You'll have ample power, it will rev just as quick as a 347, and the engine won't be remotely stressed. It's simple, proven, and parts are plentiful. I seriously doubt that the 351w power levels are going to be markedly different from a 331/347 unless you really start getting crazy with cams/compression. If the 351w is able to break the tires loose in 3rd/4th, the hopped up 331/347 will likely do the same.

I think you're over-analyzing this part of the build. The engines are very similar and the differences between a 331/347/351w are on the cusp of imperceptible aside from on a dyno and at what RPM peak power comes in (even though they will be close in power band).

 

[Ted]

I probably am over-analyzing it. Note that the breaking tires loose in 3rd an 4th was the 408 (which is probably a 500+ HP motor) not the 351, which he estimated around 400. Some of this also has to do with rear end gearing, and I'm not sure what he was running there.

Horsepower wise I expect it'll be about the same, but theoretically a 351 vs. a 331 should move the power band down a bit, probably around 500 RPM or so and change that torque profile.

50 lbs if roughly 2-2.5% of total weight of the car. So not hugely significant, but it's there. Acceleration wise I agree it won't be particularly noticeable, it'll just be fast. What I'm more going for are some of the things that are less perceptible on paper, like generally being nimble and free-revving. Those are the sorts of minor details that I do notice. Additionally, although people say they still have plenty of room to work with the 351 vs. the 302, the 302 is smaller and thus more room to work underhood, and more clearance.

When you read reviews about the original 289 vs. 427 Cobras, the general consensus has typically been that the 427 is faster no doubt, but the 289 is more balanced and handles better. This is going to be a street car but I do imagine once it's done it'll be something I'll start taking to track days, or spend time looking for some more windy backroads (we do actually have some if you go to the Missouri side of the border here) where the less weight will be more noticeable.

Yeah, I'm sure I'm overthinking it, but reduced stress is less of a concern in my case. If this thing sees 5,000 miles a year I think that will be pretty high.

 

[FormerHangie]

I probably am over-analyzing it. Note that the breaking tires loose in 3rd an 4th was the 408 (which is probably a 500+ HP motor) not the 351, which he estimated around 400. Some of this also has to do with rear end gearing, and I'm not sure what he was running there.

Horsepower wise I expect it'll be about the same, but theoretically a 351 vs. a 331 should move the power band down a bit, probably around 500 RPM or so and change that torque profile.

50 lbs if roughly 2-2.5% of total weight of the car. So not hugely significant, but it's there. Acceleration wise I agree it won't be particularly noticeable, it'll just be fast. What I'm more going for are some of the things that are less perceptible on paper, like generally being nimble and free-revving. Those are the sorts of minor details that I do notice. Additionally, although people say they still have plenty of room to work with the 351 vs. the 302, the 302 is smaller and thus more room to work underhood, and more clearance.

When you read reviews about the original 289 vs. 427 Cobras, the general consensus has typically been that the 427 is faster no doubt, but the 289 is more balanced and handles better. This is going to be a street car but I do imagine once it's done it'll be something I'll start taking to track days, or spend time looking for some more windy backroads (we do actually have some if you go to the Missouri side of the border here) where the less weight will be more noticeable.

Yeah, I'm sure I'm overthinking it, but reduced stress is less of a concern in my case. If this thing sees 5,000 miles a year I think that will be pretty high.

If you can get half a day off on October 11th, go do this: https://www.tracknightinamerica.com/events/1991287-track-night-2018-topeka-october-11. Sign up as a novice, they have a very nice setup for first time track drivers. Pretty much any car will do, especially in the novice group.

That's at Heartland Park Topeka:

I'm not sure what configuration they use for this event, but whichever one it is, I think you'll find that you spend more time braking and turning than accelerating. If it were me, I'd go with the lighter engine that has more room under the hood. The Roadster you're building does have the engine set back fairly far, but that's still 50 extra pounds that will be mostly on the front wheels. If you're mostly looking at taking it to the strip, then by all means get the 351, but for road course use, either the 302 or 331 is plenty.

I'm not familiar at all with the specifics of small block Fords, so I can't help on valve sizes. There are people who make a living doing that sort of thing, I would let one of them be my guide.

 

[Ted]

If you can get half a day off on October 11th, go do this: https://www.tracknightinamerica.com/events/1991287-track-night-2018-topeka-october-11. Sign up as a novice, they have a very nice setup for first time track drivers. Pretty much any car will do, especially in the novice group.

That's at Heartland Park Topeka:

I'm not sure what configuration they use for this event, but whichever one it is, I think you'll find that you spend more time braking and turning than accelerating. If it were me, I'd go with the lighter engine that has more room under the hood. The Roadster you're building does have the engine set back fairly far, but that's still 50 extra pounds that will be mostly on the front wheels. If you're mostly looking at taking it to the strip, then by all means get the 351, but for road course use, either the 302 or 331 is plenty.

I'm not familiar at all with the specifics of small block Fords, so I can't help on valve sizes. There are people who make a living doing that sort of thing, I would let one of them be my guide.

@bradg33 keeps on trying to get me to go to the various track nights and thus far I've not been able to make any. I'm also somewhat concerned about blowing up my E55 on the track, which is the only car I have that would be worth tracking. It does have 227k miles on it.

That said I'm not a stranger to performance driving and agree with you that you spend a lot less time accelerating than turning. This was about half of my drive to town every day for 6 years:



Many of us who lived around there knew that road very well, as well as the surrounding roads and found the "8 minute" estimate from Google maps to be on the high side. I'll just leave it at that.

And that's part of why I'm leaning now towards the 331. I had my V12 Jaguar, my 3000GT VR-4, my liter class sportbikes (along with a bunch of other motorcycles), various other cars and trucks that I ran on that road. With any vehicle knowing how to drive it and what its strengths and limitations are matters, but from a general enjoyment and satisfaction perspective, lighter weight tended to be more fun.

I am not and never have been into drag racing, and even if I was, I don't really think a Cobra is an ideal drag car. While I do want it to be reliable, this isn't something I'm looking to get 200k miles out of, and also realistically as a general street car the engine will be understressed on the whole. So I'm generally not all that worried about the engine being overstressed. It's not going in an airplane, and if it was I would be going with the smaller engine anyway to make it lighter weight. I'd also be going with an aluminum block. Note, our dearly departed friend Ben Hass (@N801BH) put a 347 built on an aluminum block in his Zenith 801. It was reliable for him.

 

[jsstevens]

I do not have nearly the experience with engines and builds you have, but reading through all the discussion, I remember what an experimental aircraft builder told me just before my first flight in an LSA: "Horsepower's nice, but weight's the thing." I think you're on the right track with the 331. Colin Chapman would be happy with the keep it light mantra as well.

John

 

[FormerHangie]

@bradg33 keeps on trying to get me to go to the various track nights and thus far I've not been able to make any. I'm also somewhat concerned about blowing up my E55 on the track, which is the only car I have that would be worth tracking. It does have 227k miles on it.

That said I'm not a stranger to performance driving and agree with you that you spend a lot less time accelerating than turning. This was about half of my drive to town every day for 6 years:

View attachment 67564

Many of us who lived around there knew that road very well, as well as the surrounding roads and found the "8 minute" estimate from Google maps to be on the high side. I'll just leave it at that.

And that's part of why I'm leaning now towards the 331. I had my V12 Jaguar, my 3000GT VR-4, my liter class sportbikes (along with a bunch of other motorcycles), various other cars and trucks that I ran on that road. With any vehicle knowing how to drive it and what its strengths and limitations are matters, but from a general enjoyment and satisfaction perspective, lighter weight tended to be more fun.

I am not and never have been into drag racing, and even if I was, I don't really think a Cobra is an ideal drag car. While I do want it to be reliable, this isn't something I'm looking to get 200k miles out of, and also realistically as a general street car the engine will be understressed on the whole. So I'm generally not all that worried about the engine being overstressed. It's not going in an airplane, and if it was I would be going with the smaller engine anyway to make it lighter weight. I'd also be going with an aluminum block. Note, our dearly departed friend Ben Hass (@N801BH) put a 347 built on an aluminum block in his Zenith 801. It was reliable for him.

Sounds like you know what you want. There were five or six track nights at Heartland this year, should be plenty of opportunities next year. The Track Night concept is to have an event that's lower key and less of a commitment than a track day, and they have a run group just for new/low time drivers.

I do not have nearly the experience with engines and builds you have, but reading through all the discussion, I remember what an experimental aircraft builder told me just before my first flight in an LSA: "Horsepower's nice, but weight's the thing." I think you're on the right track with the 331. Colin Chapman would be happy with the keep it light mantra as well.

John

Any of the engines Ted has been looking at should be plenty for that car. People keep thinking they need/want huge amounts of power in a car, but cars set up like that are not really that satisfying to drive.

 

[Ted]

I do not have nearly the experience with engines and builds you have, but reading through all the discussion, I remember what an experimental aircraft builder told me just before my first flight in an LSA: "Horsepower's nice, but weight's the thing." I think you're on the right track with the 331. Colin Chapman would be happy with the keep it light mantra as well.

Coming from the Jaguar world, we often quoted the "Reduce weight and add lightness" mantra, even though Jaguar's mantra was "Grace, space, pace." Most of us were modifying the cars in some way, shape, or form, typically removing a number of the pieces, parts, and complexities that Jaguar put in that didn't add. Especially if they were related to emissions.

The point about weight vs. horsepower is very true. Just look at liter class sportbikes for extreme examples of that. Sure, it's only a 1.0L engine making ~120 HP, but when the total weight of bike + rider is around 600 lbs...

Even then, my wife's Triumph Daytona 675 was in many ways more fun than my RC51 because it was about 50-100 lbs lighter.

Sounds like you know what you want. There were five or six track nights at Heartland this year, should be plenty of opportunities next year. The Track Night concept is to have an event that's lower key and less of a commitment than a track day, and they have a run group just for new/low time drivers.

Any of the engines Ted has been looking at should be plenty for that car. People keep thinking they need/want huge amounts of power in a car, but cars set up like that are not really that satisfying to drive.

In the Jaguar world there was the constant debate of V12 vs. I6 in the XJ-S. The point often made was that the I6 was more nimble being a couple hundred lbs heavier, and the V12 was just bigger, more complex, and harder to work on. On the whole that was correct although there's something about a V12, and for the grand touring sort of driving I was doing at the time, it was a great engine but that was more for highway touring. The XJ-S is also a bigger, heavier car all around. The people who pulled out the 6s or the 12s in favor of V8s typically ended up with a car that handled better and performed better in all respects, since even the 6-cylinders weighed close to what a big block weighed and the V12 was noticeably heavier still.

Similarly you have that debate in the Cobra world. Perhaps most telling is that the people who build these things professionally have pointed out is that a lot of times the most satisfying cars they build are ones with just a standard 302 in them.

 

[Bill]

Just look at liter class sportbikes for extreme examples of that. Sure, it's only a 1.0L engine making ~120 HP, but when the total weight of bike + rider is around 600 lbs...

BMW S1000RR, 199hp at the crank, 459# fully fueled. It's the sickest vehicle I've yet owned/ridden/driven. Absolutely stunning and breath taking. Fast just doesn't describe it. Got rid of it because at middle age, the riding position was pure torture.

 

[Ted]

BMW S1000RR, 199hp at the crank, 459# fully fueled. It's the sickest vehicle I've yet owned/ridden/driven. Absolutely stunning and breath taking. Fast just doesn't describe it. Got rid of it because at middle age, the riding position was pure torture.

Looked it up and my RC51 was rated at 133 HP, and 440 lbs. With me that put it at around 620 lbs.

I just loved the visceral nature of the thing and its seemingly limitless midrange. Got rid of it largely because it was hard to ride under 90 MPH.

 

[Ted]

Yesterday was the big day - the Cobra arrived! Many people will recognize the trailer, because Stewart Transport transports many RVs and other kitbuilds. Basically they tend to transport Factory Five kits westbound from Massachusetts and then RV-whatevers, etc. eastbound.

A lot of people on the forums complain about Stewart and frankly I don't understand why. My "completion date" was 9/8, and it took about 3-4 weeks for it to arrive at my house, which is exactly what it looked like it would be. Want overnight call FedEx and it'll cost you 10x the price. For $1300 from MA to my house in the middle of the country, it would've cost me more to do it myself just in fuel, hotels, tolls (not to mention wear and tear on the truck and trailer). Driver had good communication and was friendly. No complaints.

I did my inventorying. There were a few items that were missing or wrong. I am also fairly certain that I missed some of the things that are likely missing from the kit. A lot of the parts don't have part numbers on them or aren't necessarily clearly labeled. But I did find a few significant omissions. Overall, I'm really impressed with just how much is included. Their claim is that if you have an '87-'04 Mustang and the base kit, you can build a car. From looking at the kit, they're absolutely right. It's an overall impressive arrangement.

A few friends came over (thanks @Matthew !) and helped me get the car off the trailer and in the garage. Because the first thing you have to do is pull the body off anyway, we pulled the body off and that made it much easier to pick up the frame. More handholds on it and plus probably removed about 75-100 lbs. I would guess that the frame as it sits is around 400 lbs or so. For the 4 of us it wasn't bad to pick up really. 6 people probably would've made it a bit easier.

So now it's in the garage, and I have to start making real design decisions. Well, and tell Factory Five what they screwed up.

 

[Ted]

Oh, right. Pictures.

 

[PaulS]

Coyote engine, quit screwing around, make it a beast.

 

[Ted]

Coyote engine, quit screwing around, make it a beast.

No.

I personally don't understand putting a Coyote in these things. The engines are too big so they don't fit great. Plus they're heavier (albeit not by much).

Making 700 HP is ridiculous in a 2400 lb car. You just can't put it to the ground on street tires. Factory Five says that they recommend 300-350 HP for a best balanced street car. Some people like to flex their muscles and say "I'm a better driver! I can handle more power! You're a crappy driver!" Whatever. Breaking the tires loose in 3rd and 4th gear isn't fun. You just can't put it to the ground.

It'll either be some sort of 302 derivative or maybe a 351. A friend of mine built a Cobra with a 351W and then put in a 408 stroker after he blew up the 351. He said if he could do it again he'd do a 302 derivative. Reduce weight and add lightness. I would do an aluminum block but those cost too much.

 

[rtk11]

When did Stewart Transportation start using child labor? Whatever the case, they got your Cobra on a flat bed and backed into your driveway like a pro!

Great looking Cobra! Looking forward to the next steps!

 

[Ted]

When did Stewart Transportation start using child labor? Whatever the case, they got your Cobra on a flat bed and backed into your driveway like a pro!

Great looking Cobra! Looking forward to the next steps!

I'm fully planning on using child labor for this build.

 

[SCCutler]

A nice 302, five-speed, fairly tall gearing, done. Well-sorted, understressed, handle well, fun, last forever.

 

[Matthew]

This sticker was on the body. It should have added, "Warning: may cause increased heart rate, rapid breathing, and dilated pupils."

 

[Ted]

A nice 302, five-speed, fairly tall gearing, done. Well-sorted, understressed, handle well, fun, last forever.

It might be a 302, but still figuring 331 or maybe even 347. My heads are going to need some airflow or else be too big. Revs or more displacement.

Not planning on too tall of gearing, but we'll see. I'm talking with some engine builders on what they recommend for redlines on their blocks. 6500 is what I'm seeing as the norm on those blocks. I'd like a higher revving engine that'll scream and better support a big lopey cam.

 

[SCCutler]

It might be a 302, but still figuring 331 or maybe even 347. My heads are going to need some airflow or else be too big. Revs or more displacement.

Not planning on too tall of gearing, but we'll see. I'm talking with some engine builders on what they recommend for redlines on their blocks. 6500 is what I'm seeing as the norm on those blocks. I'd like a higher revving engine that'll scream and better support a big lopey cam.

I meant 302-based, of course.

You'll have enough torque, no matter what, that Laurie will be able to make smoke easily in the first three gears - so good to have a tall enough rear end to cruise comfortably at good speed without discomfort. NB: that cool exhaust note when you're runnin' the gears becomes a painful drone after an hour or so on the road. I'm not suggesting a 2.73 or anything like that - but low threes would seem the sweet-spot. Maybe a 3.31? Apologies for my ignorance, but how "over" is the 5th-gear ratio?

 

[PaulS]

No.

I personally don't understand putting a Coyote in these things. The engines are too big so they don't fit great. Plus they're heavier (albeit not by much).

Making 700 HP is ridiculous in a 2400 lb car. You just can't put it to the ground on street tires. Factory Five says that they recommend 300-350 HP for a best balanced street car. Some people like to flex their muscles and say "I'm a better driver! I can handle more power! You're a crappy driver!" Whatever. Breaking the tires loose in 3rd and 4th gear isn't fun. You just can't put it to the ground.

It'll either be some sort of 302 derivative or maybe a 351. A friend of mine built a Cobra with a 351W and then put in a 408 stroker after he blew up the 351. He said if he could do it again he'd do a 302 derivative. Reduce weight and add lightness. I would do an aluminum block but those cost too much.

About 460 hp, that's what my buddy's is, but it started up and ran well, first time. His fit perfectly, the coyote is a 5 liter (4.951L), which is a 302 (at least up to this year, now it's 307 ci). You still have to be a good driver with 300 to 350 horsepower in those cars, not something I'd let a 17 year old kid take out unsupervised. But your car, go for what you want.

 

[SoonerAviator]

About 460 hp, that's what my buddy's is, but it started up and ran well, first time. His fit perfectly, the coyote is a 5 liter (4.951L), which is a 302 (at least up to this year, now it's 307 ci). You still have to be a good driver with 300 to 350 horsepower in those cars, not something I'd let a 17 year old kid take out unsupervised. But your car, go for what you want.

I think his main complaint is that it's too big, in terms of dimensions. The DOHC of the Coyote takes up more space in the engine bay than the old SOHC pushrod 302. I can understand mixing "old with the new" on cars like these, especially if you wanted to make it truly a track-monster. Smooth powerbands, EFI/smooth throttle are much more predictable on the track than a carbed pushrod V8. However, for nostalgia and general romping around town, the old SBF is just fine.

 

[Ted]

I meant 302-based, of course.

You'll have enough torque, no matter what, that Laurie will be able to make smoke easily in the first three gears - so good to have a tall enough rear end to cruise comfortably at good speed without discomfort. NB: that cool exhaust note when you're runnin' the gears becomes a painful drone after an hour or so on the road. I'm not suggesting a 2.73 or anything like that - but low threes would seem the sweet-spot. Maybe a 3.31? Apologies for my ignorance, but how "over" is the 5th-gear ratio?

There's a lot of debate on which gearset makes the most sense. The transmission I'm looking at is likely going to be 0.62 top gear, which is pretty tall. Numerically, something like this leaves a 3.55 or 3.73 as optimal, largely to make 1st gear be reasonable.

There are folks who've done 3.27s and are happy with that, too. 3.27 is a stock gearset for a lot of Mustangs, so what I'll likely do is

About 460 hp, that's what my buddy's is, but it started up and ran well, first time. His fit perfectly, the coyote is a 5 liter (4.951L), which is a 302 (at least up to this year, now it's 307 ci). You still have to be a good driver with 300 to 350 horsepower in those cars, not something I'd let a 17 year old kid take out unsupervised. But your car, go for what you want.

Sorry, I didn't mean to imply that all Coyotes are 700 HP. But a lot of people go that route. I'm aiming for 400-450 HP. Kids won't be driving it anytime soon anyway.

It's also too big of an engine, which is my main complaint as @SoonerAviator guessed. Plus, my car was ordered (and showed up) as 302/351 mounts and a 3-link solid rear. So that's what I'm doing.

Now whether I do 302-based or 351 based, still figuring that out.

 

[SCCutler]

I so envy you this whole project!

 

[Zeldman]

Making 700 HP is ridiculous in a 2400 lb car.

No, it isn't, but yes. I know I kid you about putting in a Boss 529, but it would be waaay too much of an engine. Too much HP is sometimes not fun.

In 1984 I had a 1970 Chevy C-10. No power anything, drum brakes all around. It had a warmed over 283 that I had put in it years ago. Now all my friends had faster trucks, so I had to do something.

I bought a Chevy 427 that came with papers showing it was legal to run in NASCAR at Daytona and Talladega speedways. (back when big blocks were acceptable in NASCAR) This engine was designed to power a 4000 pound race car at 200+ MPH. In a 3200 pound pickup it was a total beast. At 100 MPH in 4th gear I could spin the rear tires. Tires back then were not as advanced as todays tires. When the tires started spinning the rear of the truck would want to pass the front of the truck. Not a fun thing in a non power steering dinosaur of a truck. I eventually put non street legal racing tires on the rear and avoided water like the plague.

According to the RPMs, gear ratio and tire size I estimated that at one time I had it up to 150 MPH, but I am hear to tell ya that it was a totally terrifying ride. After about 6 months I pulled the 427 and put in a mildly warmed over 396. The 427 went into a race car that was used to race at the old Texas World Speedway and other short track races. After a couple years I sold the car with engine to a team in Alabama.

 

[Ted]

I so envy you this whole project!

https://factoryfive.com

 

[Ted]

Too much HP is sometimes not fun.

That's really the point. If you can't put it to the ground and are breaking tires loose at high speeds, that's just not fun or useful. Can I drive a car like that? Of course I can. But I want to have fun.

 

[Bill]

Breaking the tires loose in 3rd and 4th gear isn't fun. You just can't put it to the ground.

I had a '14 Mustang with the Coyote. On a coolish day (45F), a half-hearted stab at the throttle in third gear at, say 4000rpm, would spin up both rear tires. Torsen diff, so it spun both, and that thankfully was more predictable than the 'stangs with open differentials. Still, going sideways at the end of the onramp merging into traffic is always fun.

 

[SCCutler]

https://factoryfive.com

Heh.

Maybe after I've moved to Fredericksburg...

 

[Ted]

I had a '14 Mustang with the Coyote. On a coolish day (45F), a half-hearted stab at the throttle in third gear at, say 4000rpm, would spin up both rear tires. Torsen diff, so it spun both, and that thankfully was more predictable than the 'stangs with open differentials. Still, going sideways at the end of the onramp merging into traffic is always fun.

I suspect that this car will do it as well in 3rd gear as well with what I'm building, but with 315s and a limited slip on the back it'll take a bit of aggravation.

I detest open differentials.

Heh.

Maybe after I've moved to Fredericksburg...

No time like the present.

 

[3393RP]

That's really the point. If you can't put it to the ground and are breaking tires loose at high speeds, that's just not fun or useful. Can I drive a car like that? Of course I can. But I want to have fun.

I subscribe to Hot Rod and Car Craft, been reading them forever. They repeatedly run stories about street cars that have engines producing 1,500-2,000 HP.

What's the point of that?

 

[1RTK1]

They aren't running street tires if they are racing.

Bragging rights....

Had a buddy that bought a 1000 HP street mustang.

 

[FormerHangie]

I subscribe to Hot Rod and Car Craft, been reading them forever. They repeatedly run stories about street cars that have engines producing 1,500-2,000 HP.

What's the point of that?

You get written up in Hot Rod and Car Craft, I suppose. It's certainly not for driving enjoyment, and there are no tires that fit on a street car that can put down that kind of power.

 

[SoonerAviator]

For most cars/light vehicles , 600-700HP is the limit of where it goes from streetable to unusable without racing tires/suspension. Engines are generally too finicky to idle smoothly when set up to run at high power levels. You sacrifice driveability for top end performance.


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[3393RP]

You get written up in Hot Rod and Car Craft, I suppose. It's certainly not for driving enjoyment, and there are no tires that fit on a street car that can put down that kind of power.

It irritates the crap outta me. That and features of half million dollar show cars. That has nothing to do with hot rodding.

 

[3393RP]

For most cars/light vehicles , 600-700HP is the limit of where it goes from streetable to unusable without racing tires/suspension. Engines are generally too finicky to idle smoothly when set up to run at high power levels. You sacrifice driveability for top end performance.


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Actually a modern production blown or turbocharged EFI engine with VVT or cam phasing can be very streetable and still produce upwards of 800 HP.

But what are you gonna do with it?