Hello everyone! I need your help! I have a 1938 Pontiac Sedan Deluxe 8 with original suspension. I apologize up front for the length this will probably end up being. The lever action shocks, (which I plan to have rebuilt), are not doing there job and I believe I have figured out why. The car was restored/rebuilt/modified about 16 yrs ago. Previous owner/builder removed the inline flathead 8 cylinder and replaced it with a 305 SBC, giving it power steering and brakes. I replced the original radiator with a aluminum one. Now the front of the car sits real high and I suspect the big difference in weight in those 2 items prevents the front from sitting where it's supposed to. As a result, the lever action shocks are not in a position to perform as designed. I'm going to try and post some pics below. New coil springs to compensate for the less weight would have be custom made I'm told and very pricey, with no returns allowed. So here is where I need your experience and knowledge based help. I'm not looking for a low rider look at all. I just want the front wheels to sit in the opening like they should and to get the shocks in a position to dampen as designed. Should I/can I consider cutting the coil springs, a little at a time, to get the front end down where it needs to be? And what's your best guess as to how much of the springs will need trimmed to accomplish this? Thank you in advance for any help. 2 pics of the car on the ground. One shows how close the upper control arm, (the shock basically), is to the upper bump stop. The other shows how high the front is. Thanks again!!
A good spring shop should be able to test the rate of your existing springs, along with the amount lower you want the car to be, and make them accordingly. It might be tough to measure, but you need the ride length as well.
custom made coil springs shouldn't be expensive to have made, I had a set made for a '65 Galaxie here in the UK and it cost me £160 for the pair!!
You’ll need to see how your springs sit in the seats. And the shape of the spring ends. Depends on that how you trim them. You could probably cut a coil off and it’d be about right. having new ones made shouldnt be too expensive.
Be aware that a shortened spring gets stiffer as less coils have to do more work. You might get better results when you collapse your spring in a press. It will not come back to the same height after being coilbound.
There's only about 75 lbs difference in the straight 8 & the Chevy , I wouldn't think that would cause the " nose up " position you have ? The radiator may have been 50 lbs heavier , still not enough to cause the attitude . were the springs changed?
I am looking at the same problem for my first coupe, going from the straight 8 to a nail head. The weight difference between the 2 is substantial and is centered rearward some. I am looking into springs from lighter cars. The lever action shocks need to be in their operating range. The other thing I plan to do is to put a 1" thick adapter plate between the frame and top control arm assembly so I can get a little more caster. Pontiac, as well as Buick, used different spring rates for different models. My Buick manual lists the springs that were used and capacities. Maybe a Pontiac small coupe?
Thank you all for your help. I agree the weight between the original engine and the Chevy isn't a lot, but when I talked to Eaton Detroit Spring about what information they would have to have to make springs for me, they wanted to know if there was going to be AC on the car. I asked why that was important and he said the weight of the compressor has to be taken into consideration. Hell that can't weigh that much. I'm only mentioning that to give all info. But when you have the less engine and probably trans weight, sitting back farther on the frame?? My shop manual lists the springs for both the 6 cyl and the 8 cyl models. Diameter of both was the same with the 8 cyl spring only being 3/8" longer. Doesn't mention wire size though. Still a lot of cruising weather left so I'll take it all apart over the winter and send the shocks off to be rebuilt and figure this spring thing out when I get all the info about what I have now. They are the original springs as far as I know. Thanks again ...
Thanks for that. Amazing how much I've learned in a short amount of time. I understand I need a softer spring and not just a shorter one. Although it may end up being a little of both.
Not the same thing but may help I replaced the cast iron intake on the 352 in my 65 F100 with an Edelbrock aluminum one 79 lbs original cast iron, 25 lbs Edelbrock The battery was up by the radiator core support on the passenger side Put it in the bed on the passenger side close to the cab Had to lower the truck over an inch to get the camber back to normal ( Twin I-Beams ) Ricky.
There's a fair few components in an AC system, Compressor, Condenser, Evaporator, Hoses, Pipes etc etc all adds up.
You've nothing to lose by cutting the spring as long as it fits in the pocket as mentioned. If the increased spring rate doesn't suit then you'll be looking for new springs anyway. If new springs are required you could get lucky and find something cheap and available that could work, like Aerostar springs fitting shoeboxes. There must be a size chart somewhere? Even the 6 cylinder version might be worth a try , but finding them in usable condition might be a challenge. Chris
I fought a problem like this on a 40 chevy coupe with knee action shocks. Put in a sbc in place of the 6 and the thing gained about 2" in height and rode/drove like a rock. Best I ever got was a set of pinto springs, 6 cyl. I think, that brought it down and it could actually be driven. Finally just changed it all to a r&p and no more problems.
Look at comparable spring rates for a Ford Aerostar van. Same diameter possibly a little taller,. We cut a coil off and it brought wheel arch closer to tire on a 38 Buick
Same deal here original straight 8 replaced with smallblock sat nose high, cut a couple coils out sat low rode like crap replaced with 6 cyl. springs sits the way I like it doesn't bottom out or drag across manhole covers any more. I believe I got them from Kanter 25 years ago Can't quite remember old guy stuff
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