What I'm spending my AMUs on ...

Crashnburn

Crashnburn

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Crashnburn
https://classiccars.com/listings/vi...bird-trans-am-for-sale-in-eugene-oregon-97403

I bought the car in March, 2018, after at least two months of internet searching. Its a 1981 Pontiac Firebird Trans Am Special Edition. Same body style that Burt Reynolds drove in the first two Smokey and the Bandit movies, except its a coupe, and not a T-Top. 1981 was the last year Pontiac was allowed to sell their own V-8, and my 4.9L is the biggest Pontiac V-8 available for that year. There's also a Chevy 5.0 L, but I understand it doesn't make as much stock as the 4.9L (non-turbo charged) Pontiac engine.

I had a Firebird Formula from 1977 to 2005, when I got married and my wife wanted to garage her car. The car had a 4 speed manual, 4 barrel carb, and a 400 CID engine. All I needed to do to speed up was to think about it, and you'd feel yourself sinking back into the seats. This one, you actually have to press the gas pedal.

Also, this one has an 3 speed automatic, but there is a 4 speed auto, with lockup converter, and overdrive that is almost plug and play compatible with the stock tranny.

1981 was the first year that Firebirds didn't come with a limited slip differential, but a previous owner replaced the 3.08 rear end with a 3.23 Posi-Trac rear end. I lost a little bit of top speed with that swap, but low end torque is better. A 4 speed tranny will give me even better low end torque, and at the same time, get my top speed back, and then some. All I need are more AMUs.

In this case Automotive Monetary Units!
 
Youre my hero. That's my mid life crisis car. As if a mid life crisis plane wasn't enough...
 
IIRC, in the movie, they made that car fly. Not that I'd recommend it, but...

Looks like fun, enjoy.
 
Nice. Our high school colors were black and gold, so OF COURSE there was one girl who drove a similar ('77 or '78) black & gold Trans Am our senior year.

It's a slippery slope. I've started looking (casually) for a toy car for my wife... yellow first-gen Mustang convertible. I figure she's got a little love coming for putting up with my airplane habit.
 
Congrats! Crazy what old cars sell for now. You couldn't give away an 80's Camaro or Firebird in the early 2000's now they are bringing mid 20's... I had the opportunity to buy a car just like that in similar shape for 8k around 2007 and told him he was crazy. What a fool was I! Wonder if he still has it.. haha
 
Would like to buy a classic,but all my money goes to flying my retirement airplane,and boating. Good luck with the car.
 
Thanks all. My wife doesn't want much. Just an early model Shelby Cobra Mustang. They are about 1K AMUs so it's a given that's not happening! I'm 64. I don't expect to have a midlife crisis for at least 10 more years.

Also, the car drives like a go-cart on steroids! I got the car to tide me over until I retire and can commit some serious aviation!
 
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JCranford said:
Youre my hero. That's my mid life crisis car. As if a mid life crisis plane wasn't enough...
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Yea....my Lance was a midlife crisis too. I filled the seats with some bimbo and her friends.:blowingkisses:



Oh wait.....that’s my wife and kids. Damn.....didn’t work out as planned. :idea:
 
I'm looking for a 73 Corvette. Last year with bumpers. Exempt from smog checks (75 and newer is still required). A big deal in CA.
 
I like the ‘68 Firebird most out of the lineage, second probably being the “Bandit” editions. My uncle (also a pilot) let my cousin and I take out his 1998 Fire Engine Red Trans Am WS-6 joyriding when we were 15, lol. Gawd that was a mean car. I’m surprised we didn’t wreck the thing, but we could barely get it into 1st/2nd without barking the tires just rolling around the neighborhood streets.


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My buddy and I started installing a Vintage AC in the car, but we ran out of steam about the time I needed to get it smogged, so I took it to a little hole in the wall operation that is supposed to do good work. The AC works great.

Then, I needed to replace the plugs, spark plug wires, and distributor cap. I had the work done; getting the spark plug wire off the right rear plug was a real PITA. The car runs a lot better.

My Firebird has High Energy Ignition, and the required gap is 0.060. The plugs are Bosch, and they recommend 0.040. I can pull a plug to see what the gap is, but what do you folks think it should be?
 
="Cruzinchris, post: 2600964, member: 31133"]I'm looking for a 73 Corvette. Last year with bumpers. Exempt from smog checks (75 and newer is still required). A big deal in CA.
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The 73 has one chrome bumper, the rear. Still a beautiful car!

I had an 81 and a 90, miss them both.
100_1983.jpg
 
I do like the 60’s Chevelle , Mustang too, yes, even the Firebird.

With the plane, motorcycle, deer camp & a few other things I better skip the classic car.
 
In high school the rich kid's dad bought him a brand new 1978 Trans Am, black just like this one with gold trim. Speaking of trim, he got some with that car...

Envious, we all were...
 
Crashnburn said:
My Firebird has High Energy Ignition, and the required gap is 0.060. The plugs are Bosch, and they recommend 0.040. I can pull a plug to see what the gap is, but what do you folks think it should be?
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I'd leave it. The wider gap requires higher energy to jump the gap. If it's running fine, you're OK. Plus the gap will widen on its own as the plugs wear from mileage.

As for uniform gap, most plug manufacturers now pre-gap their plugs. They're usually pretty consistent.

I'm a Ford guy, so I could be wrong, but I believe HEI can run from a .035" to .085" gap, and GM set the factory gap, as you indicated, at .060"
 
Crashnburn said:
My buddy and I started installing a Vintage AC in the car, but we ran out of steam about the time I needed to get it smogged, so I took it to a little hole in the wall operation that is supposed to do good work. The AC works great.

Then, I needed to replace the plugs, spark plug wires, and distributor cap. I had the work done; getting the spark plug wire off the right rear plug was a real PITA. The car runs a lot better.

My Firebird has High Energy Ignition, and the required gap is 0.060. The plugs are Bosch, and they recommend 0.040. I can pull a plug to see what the gap is, but what do you folks think it should be?
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.040 will be fine. Step it up to .050 if you run into issues, but I seriously doubt it's going to matter unless you're racing the thing.
 
SoonerAviator said:
.040 will be fine. Step it up to .050 if you run into issues, but I seriously doubt it's going to matter unless you're racing the thing.
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Thanks all, and the closest it's ever going to be to a race track is the parking lot. :)
 
We've made the decision to spend a good portion of our AMUs on local restaurant take out. No chains, I figure they'll do fine one way or another. But we want to identify the places that we value as neighbors and help them out.
 
Way back in the mid 80s, a customer came in with a 1975 Firebird, cloned Formula. It had a bad rod knock, so he went to the local junk yard and came back with an engine.

It sat in our shop for months, waiting for the guy to pay first. He finally came back and said he wanted to sell it. So I bought it.

I opened up the junkyard motor and instead of a 350 it was supposed to be, it was a 455 instead. I rebuilt the 455, adding some horsepower parts, and added a tri-power carburetor set up. Someone had added the hood with the two snorkel fresh air intakes and added the Formula wheels, and the flip up on the trunk, making it a cloned Formula Firebird.

I put in the 455 with a T400 Automatic, and changed the rear gears to a 3:55 ratio. Since we also sold race gas, I could mix some race gas with regular gas and get the octane rating to meet with the compression, plus add tetra-ethyl lead to the gas. With the extra Octane I was able to push the timing past the stock limits.

I never saw taillights when street racing. Something I do not condone nor endorse. On the drag strip it was fast enough to require a roll cage, so I had to reduce the throttle to keep under that speed.

It was yellow, an awful looking yellow that had seen much better says. I had a ton of fun taking money from the college kids, beating them in their new Corvettes and the current Trans Am model.

The picture below is a much better looking and similar looking Firebird, not the one I had.


Screen_Shot_2016-07-13_at_4.43.12_PM_large.png


A friend of mine had a '72 Camaro, 454 power with a 4 speed. The only reason I would beat him on a quarter mile is because he had to shift gears. I would beat him by 6 feet at the finish line, consistently. Until he put an automatic in. Then the outcome would depend on who had the best reaction time and less wheel spin at the starting lights.
 
Now that's a pretty car. Hopefully it's not a rattle trap, but a roll of Dynamat (I've been using Rockmat, a clone, and been happy with it) will fix it up if it is rattly.

I'm assuming the current transmission is a TH350, and so the 4-speed auto options would be either the 200R4 or the 700R4. The 700R4 is a better transmission (especially if you get one of the later ones - if I'm remember correctly early ones had 27-spline input shafts and later ones had 30-spline), but the ratios on the 200R4 were significantly better spaced. Still gives you a deeper 1st gear than the TH350 for better off the line, but your 1-2 shift isn't so significant of a drop. The 700R4's 1-2 shift is about a 45% drop, so you wind it up in 1st gear, get to redline RPM, then it shifts and falls flat on its face. My wife's Avalanche had a 4L60E (later electronic version of the 700R4) and the 1-2 shift was awful. 200R4s aren't known for being super strong but should be plenty behind a stock 4.9 of the era, especially if you put in some beefed up parts.

Congrats!
 
This is all from internet research. The 700R4 requires quite a bit of work to mate it with the torque converter, but the 200R4 is an easy fit, the only modification is a different hole on the frame for the transmission's support member. There are all sorts of overhaul kits for the 200R4, up to at least 600 HP.

I currently have the stock TH350, and as finance permit, want to replace it with a 200R4. I have aspirations of becoming a shade tree mechanic, so I'll probably hire it done.

My current engine is the 4.9L NA Pontiac, and is rated at 150 HP. My 1977 Formula had a 6.6L rated at 220, but apparently, it made more than that. All I had to do to speed up was to think about speeding up. The T/A takes a bit more than that. The more I learn about my Formula, esp. the engine, the more I wish I had it back.

My next project will be to replace the fixed shaker hood flap with a moveable one, so as the engine speed increases, the flap opens up more. I've heard that's good for about a 6 HP increase.
 
The Firebird would still occasionally overheat at highway speeds, and I researched aftermarket radiators. Before I pulled the trigger, I installed my new coolant recovery jar cap, and noticed that while the radiator cap said it was 15 PSI (per factory spec), it was some aftermarket cap, and not an AC Delco like the one that came with the car.

After a lot of shopping, Amazon had the best price, and because I'm on my wife's Prime account, I get free shipping on almost everything, I pulled that trigger. (Shipping from any other source was more than Amazon's price for the cap!)

Last week, before I changed the oil and filter, I poured in a can of engine flush, and let it idle for 10 minutes. At the end, the Check Engine light was on. I turned the engine off while I got my wife to monitor me driving up the blocks. When I turned the engine on, no Check Engine light.

Yesterday, I drove it to the post office to mail some bill payments. I ran the A/C for a while driving there, and the engine temperature went to maybe 240 degrees, but no check engine light. As soon as turned the A/C off, the engine cooled down to 220 F.

I ran the A/C on the way home, on a route with fewer stops, and a few miles on the Freeway. The Check Engine light never came on, and the engine temp was at most 230F.

I'm beginning to suspect the Check Engine light was because of overheating, and the overheating was because the old radiator cap couldn't hold 15 PSI, and letting the water turn to steam in the engine block; and steam is a lot less effective at heat transfer than water. Also, when I checked the coolant recovery jar when I got home, the level was lower than it was with the old radiator cap. What do you guys think? Does my theory hold water, so to speak?

Next up is fasten down the new battery tray, install the battery clamp bracket, and the battery clamp. I was able to find all the piece parts I needed at Ames Performance Engineering.

The thing I really want for this car, though, is more power. The 4.9L N/A V8 does an OK job when I tromp on the loud pedal, but I only had to think about going faster in my Formula Firebird with a 6.6L.
 
I don't know... 220 - 240 is way too high in my opinion. The thermosat should hold temps to 195 degrees (or around there.) Have you changed the thermostat yet? You can also take the one in your car and put it in water on the stove and see if it opens when the water is boiling (212 degrees.)

Have you verified that the engine temp gauge is reading correctly? If not, maybe the temperature sender is suspect?

Before buying a new radiator, you can take yours out and, if it has metal end tanks, the radiator shop should be able to "rod out" your radiator (sticking a rod in each coolant passage to clear obstructions) and re-braze your end tanks back on for not a lot of money.

The radiator cap is likely part of the problem and allows water under pressure not to boil (and steam over as you have seen.) But it sounds like (to me) there's still another problem in the cooling system.
 
rtk11 said:
I don't know... 220 - 240 is way too high in my opinion. The thermosat should hold temps to 195 degrees (or around there.) Have you changed the thermostat yet? You can also take the one in your car and put it in water on the stove and see if it opens when the water is boiling (212 degrees.)

Have you verified that the engine temp gauge is reading correctly? If not, maybe the temperature sender is suspect?

Before buying a new radiator, you can take yours out and, if it has metal end tanks, the radiator shop should be able to "rod out" your radiator (sticking a rod in each coolant passage to clear obstructions) and re-braze your end tanks back on for not a lot of money.

The radiator cap is likely part of the problem and allows water under pressure not to boil (and steam over as you have seen.) But it sounds like (to me) there's still another problem in the cooling system.
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Thanks for the suggestions. (Edit) I looked up the thermostat temperature in my Haynes manual. You called it- 195 F. I’ll be getting one soon. (Edit) I looked a little closer at the manual. The thermostat should start opening at 195 and be fully open at 220 F. That’s what I’m seeing, now. Thanks, though for getting me to verify. Also, 3 shops have driven the car, and none have said anything about the engine temperature.
 
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When I was in high school, I bought a 1973 Trans Am 455SD off the showroom floor at a Pontiac dealer. I'd been saving money for years, paid about half of the $5,500 cost in cash and my dad financed the rest for me.

It was the last of the muscle cars, and I had a blast in it.
 
When I was 14, my Dad gave me the title to his somewhat neglected '71 Triumph Spitfire, said "fix it and it's yours."

HS girls don't JUST dig muscle cars. :cool:

I love my Dad, and I love my Spitfire. They are both under my roof tonight, one of them moves better than the other. :rolleyes:
 
3393RP said:
When I was in high school, I bought a 1973 Trans Am 455SD off the showroom floor at a Pontiac dealer. I'd been saving money for years, paid about half of the $5,500 cost in cash and my dad financed the rest for me.

It was the last of the muscle cars, and I had a blast in it.
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You got a great deal! My 1977 Fomula with a 6.6 (400) manual 4 speed, position-trac, power steering, power brakes, and A/C was $9500! And, it, too, was off the showroom floor!
 
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My first car was my Dad's first ever "new" car... a 1970 Ford Thunderbird with a 429 big block. I got it in 1984 and dang did Iove that car. The gas gauge visibly moved when I floored throttle, the disc brakes were hyper sensitive on the first application, then faded into nothing if you pumped the brakes, open differential that meant black streaks a full city block long... lots of good times in that car. Then my dad sold it when I got home from High School one day. Sigh.

Both the T-bird and my dad are gone now. I miss them both (my Dad I obviously miss dearly.)

It seems kids now-a-days don't have much of an interest in cars. I'm glad that my son has a strong interest in my Mustang from my college years. And I acquired an early Porsche 944 as a non-running project to teach him how to work on the car (including pulling and freshening up the engine, head replacement and torquing, clutch replacement, etc.), and once it's running, he'll learn to drive a car with a manual transmission with it.
 
rtk11 said:
My first car was my Dad's first ever "new" car... a 1970 Ford Thunderbird with a 429 big block. I got it in 1984 and dang did Iove that car. The gas gauge visibly moved when I floored throttle, the disc brakes were hyper sensitive on the first application, then faded into nothing if you pumped the brakes, open differential that meant black streaks a full city block long... lots of good times in that car. Then my dad sold it when I got home from High School one day. Sigh.
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My mom had a '69 LTD Country Squire wagon, complete with faux wood paneling. It also had 429, with 10:1 compression ratio. It behaved the same way you described, including burning through 100 octane premium Chevron gas.

My siblings and I routinely used it to drive from Albuquerque to Durango on weekends to ski at Purgatory. We would hoop it up to Durango traveling over the speed limit (quite a bit over :D ), then wait about 45 minutes before calling home to say we had just arrived.

The car weighed something like 5,200 lbs, but it would really light up that right rear tire. :D
 
I had a birthday almost a month ago, and one of my presents was a 2nd Generation Firebird guide to restoration. That got me to looking at my build sheet, which I found under the driver's seat.

My car is an 81 model, and was the first year they came w/o posi-trac standard. My build sheet shows a G80 posi-trac; but I looked up G80's and they are locking differentials, at least in trucks.
I've proven the differential needs special gear oil, already. The internet says G80 is posi-trac in cars, and locking in trucks.

Also, using GPS speed, my car is about 5% slower than what the speedometer says. The factory code on the differential says it's 3.08, as does the build sheet. However, the 5% difference is about the same difference between the 3.23 and the 3.08. I know it's very possible that someone changed it out for a 3.23 and kept the original case. The 3.23 is probably 5% bigger in diameter than the 3.08, and I wouldn't be surprised if GM used the same case size of all three of the gear ratios offered that year, to keep inventory part numbers down. I have the same size tires as came standard 70R15's.

Any thoughts?
 
Jack up the rear end of the car and spin the rear tires while in neutral. If both spin the same direction, you have a limited slip differential.

Now mark your driveshaft with chalk. If it takes you 3 turns (3.08 turns really) to get the chalk back to the same place, you've got a 3.08 differential. If it takes 3.25 turns of the tire to get the chalk back to the same starting point, you will have had someone change the rear ring and pinion on you.
 
It was also common for old speedometers to be less accurate. But as noted, count revolutions. You can also count teeth if you pull the diff cover (and it’s a good idea to change the fluid if you haven’t yet).

Did you get the temperature figured out? 220-240 is way too hot in my opinion. I’d put a 180-190F thermostat.
 
Ted DuPuis said:
It was also common for old speedometers to be less accurate. But as noted, count revolutions. You can also count teeth if you pull the diff cover (and it’s a good idea to change the fluid if you haven’t yet).

Did you get the temperature figured out? 220-240 is way too hot in my opinion. I’d put a 180-190F thermostat.
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Thanks. I had all the fluids services after I bought the car two years ago. A 195 degree thermostat is stock, and everything if fine until I turn the AC on. There's just not enough CFM for the reduced delta-T with the AC running. As soon as I turn off the AC, the coolant temperature starts dropping.

I have a 1500 CFM pusher electric fan, with digital controller on order which will sit in front of the condenser and blow more air on it, on order. It looks like the simplest way to get it in is to remove the front air dam and bring it up from below.
 
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Jealous. I’d love to have an old car to work on, but first a place to work on it. Our garage is occupied by the car of SWMBO and my Leaf, which has to be charged.

So far, attempts to build a stand alone workshop/garage have been resisted.
 
I think I finally have the temperature figured out, thanks to my mechanic. When I drove the car to the shop, it ran like a dream, but when I drove it away, after they installed the aux fan, it hesitated, surged, stalled, and wouldn't always idle. I suffered with it for a while, then when it got really bad, I took it back, with a litany of other problems.

In the course of fixing the poor running, he found the dash temperature gauge was way higher than what his IR heat gun said, and what the computer was telling him. The dash gauge was reading 260 -280, and the IR gun and computer were saying 195, which is the thermostat opening temperature. He's going to try a new sensor to see if that fixes the problem. If not, it's a problem in the dash gauge. Either way, with the engine driven flex fan, the Cold Case radiator, and auxiliary fan, there should never be a problem with overheating, even running the AC full out on a God-Awful HOT day!
 
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Got my car back last night. The shop owner and I were talking. He said he hadn't thought to check the voltage regulator (VR); that could make gauges read high if it the voltage was too high. Luckily, my dash gauges include voltage, and I think that the VR could be the issue.

At idle, the voltage is 13.9 (about) and anything faster than idle, it's about 14.9; within safe range, but I think it should pretty much be at 13.9, independent of engine speed. Also, at idle, it seems my engine temp seems to drop awfully fast, and heat up really fast at speed. I need to double check that, though. Easy enough. Get the engine warm. Then, while stopped, let the engine idle, and in park or neutral, speed the engine up, and see what happens with the temperature gauge. I think that if the temperature varies immediately with engine speed, I've found the problem. I'm sure changing out a VR will be easier than chasing a sneak circuit.

It'll probably turn out I fought a problem that didn't exist, but at least I'll never have to worry about my engine overheating.
 
Just a thought, since you mentioned the voltage regulator. Check the grounds. A 39 year old car might have developed a little corrosion along the way.

Make sure there is a good ground between the engine and frame, frame and body and body and engine.

(don't ask how I learned that lesson...)
 
Zeldman said:
Just a thought, since you mentioned the voltage regulator. Check the grounds. A 39 year old car might have developed a little corrosion along the way.

Make sure there is a good ground between the engine and frame, frame and body and body and engine.

(don't ask how I learned that lesson...)
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Thank you. That's a great suggestion. And, I won't ask.
 
I’m surprised this isn’t a NARCO thread. Anyway, I have solved the scary overheating according to the temperature gauge problem. The voltage regulator is higher voltage output than the temperature gauge expects, so more current is drawn than expected for any given temperature.

The original VR was slightly higher than spec, and the new VR is slightly under the high limit. The 0.7 volt forward drop of a silicon diode didn’t change the reading all that much.

Yesterday, I replaced that diode with a 2.0 V Zener diode and went for a cruise. With the AC running full blast, the gauge got up to just over 220, which is where the thermostat is fully open, and cooled quickly to 195 when I turned the AC off.

So I didn’t need the Cold Case radiator nor the auxiliary electric cooling fan but they are staying in; and I don’t think I’ll ever need to worry about the car over heating again!
 
rtk11 said:
I don't know... 220 - 240 is way too high in my opinion. The thermosat should hold temps to 195 degrees (or around there.) Have you changed the thermostat yet? You can also take the one in your car and put it in water on the stove and see if it opens when the water is boiling (212 degrees.)

Have you verified that the engine temp gauge is reading correctly? If not, maybe the temperature sender is suspect?

Before buying a new radiator, you can take yours out and, if it has metal end tanks, the radiator shop should be able to "rod out" your radiator (sticking a rod in each coolant passage to clear obstructions) and re-braze your end tanks back on for not a lot of money.

The radiator cap is likely part of the problem and allows water under pressure not to boil (and steam over as you have seen.) But it sounds like (to me) there's still another problem in the cooling system.
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Back in 1979 I had a 1966 Chevy Fleetside Longbed pickup truck that needed its radiator worked on. There was a guy who had retired from our office who owned a radiator shop and my wife took the truck to him while I was on the road on a job. She said, when I returned, that I could have had a a new single core radiator put in, or for some inconsequential amount more she should have a double core radiator put in, so she spent the extra coin and had the double core put in. Worked like a champ. Smart move on her part (and no surprise, either). I think she had the thermostat and radiator cap replaced at the same time. Needless to say, I didn't have a problem with the cooling system again in that truck.
 
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