: 368 Engine Build



snick1980
09-05-10, 01:20 PM
Hey, my name is Nick and this is my first post. I'm sure there is a few posts about my question but what are some gains I can get out of my 1980 Cadillac Fleetwood with a 368 in it? Not looking to build alot of hp....example 400, but I would like some torque. Is it worth putting money into? Are the 80's 368 interchangable with the 472/500 parts? can i bore/stroke it to one of these sizes? The motor has 218,900 kms on it ao I was thinking of takin er apart and reseal it, but a 472 would be mint. please let me know, thank you

drmenard
09-06-10, 12:08 AM
Putting anything in a 368 is a waste of time and money.... To get the most for your money is drop in a 472 or a 500...the motor is a drop in with some 425 parts... If you plan on doing it I can help you on what parts to look for..

snick1980
09-06-10, 11:05 AM
I would love to put a 500 in it. what would you think my 368 core would be worth? Is it still possible to get a 1970 500 block on a website with the heads?

drmenard
09-08-10, 10:14 PM
Your chances are slim of finding a 1970-500... But a stock 500 from a 75 or 76 deville should be eaiser to come by.. If you were going to spend a 2 or 3 thousand building a motor you can piece together a good motor... But if your on a limited budget that stock 500 with a new timing chain and gears advanced 4 degrees will have good power...

CADILLACSAM
09-12-10, 08:57 PM
Those early 500's r hard 2com by, But if u get get1 u got a GEM. Lots of torgue the 368 is good but like in the earlier post don't waste ur money.

deVille33
09-15-10, 07:18 AM
You could drop in a reliable 425. Not as torquey as a 500 or 427, but very reliable and easier to find. However, the junkyards are crushing these for the weight. 1980 Coupe will verify this as his JY in Texas only keeps them about 6 weeks, then they are gone.

1980coupe
12-01-10, 05:22 AM
You could drop in a reliable 425. Not as torquey as a 500 or 427, but very reliable and easier to find. However, the junkyards are crushing these for the weight. 1980 Coupe will verify this as his JY in Texas only keeps them about 6 weeks, then they are gone.

yup...thats true...not to long ago they had a clean 80 coupe and when I went back not even 3 months later it had been removed from the lot, whether sold or crushed, I don't know.

DouglasJRizzo
12-09-10, 10:54 AM
The 368 is an excellent engine, and is architecturally the same as the 472/500/425 engines. With minor tweaks, it can reliably produce acceptable horsepower and torque.

Nearly anything that works in the other V-8's will work on the 368.
Things to watch out for -
Don't over carburate it for a mild street engine it's roughly 1 CFM for 1 horsepower. So figure a smaller carb like a 390 CFM would be MORE than enough.
Valve train - weak link in all the Cadillac V-8s. There are people who sell things to keep the lifters where they should be and not shoot them through the valve covers.
Head ports are smaller on the 368. Not a problem on the street as street fuels don't respond well to huge ports in cylinder heads.
If you want to keep the original 368 there's no reason why you couldn't. It can make enough power to have the car driveable in traffic. If you were looking for all out horsepower, then the other engines would be better, but for day to day street driving, a properly tuned 368 could work well.

deVille33
12-09-10, 11:21 AM
He's got in excess of 200K on this engine. I'm not that familiar with the block, but assuming it can take a substantial overbore ( which I doubt ), it's gonna cost big time for pistons and rings. Gone are the days when it was possible to overbore a block by .125". Much easier and economical to get one of the other engines than build this one.

DouglasJRizzo
01-09-11, 02:13 PM
WHo needs to overbore? I'm a degreed engineer and own a machine shop. Just cleaning the bores up and doing a proper rebuild on the block is more than enough. Do the heads by merely cleaning up chambers and ports. You dont need humongous ports and displacement to make power. In fact, on a street engine with current fuels, smaller ports work better.

Sure a 472 or 500 would really put out the punch, as would a 425. But properly done, a 368 wouldn't be bad.

creeker
01-09-11, 03:40 PM
The 368 is an excellent engine, and is architecturally the same as the 472/500/425 engines. With minor tweaks, it can reliably produce acceptable horsepower and torque.

Nearly anything that works in the other V-8's will work on the 368.
Things to watch out for -
Don't over carburate it for a mild street engine it's roughly 1 CFM for 1 horsepower. So figure a smaller carb like a 390 CFM would be MORE than enough.
Valve train - weak link in all the Cadillac V-8s. There are people who sell things to keep the lifters where they should be and not shoot them through the valve covers.
Head ports are smaller on the 368. Not a problem on the street as street fuels don't respond well to huge ports in cylinder heads.
If you want to keep the original 368 there's no reason why you couldn't. It can make enough power to have the car driveable in traffic. If you were looking for all out horsepower, then the other engines would be better, but for day to day street driving, a properly tuned 368 could work well.

I agree, great engine, my 80 cdv. has 56,000 miles on it, the only complaint I have with the 368 is the lack of top end torque, I went on a trip a few years back
in sometimes mountain areas, it really bogged down on long inclines, besides that it's great.

DouglasJRizzo
01-09-11, 09:08 PM
I agree. I had an '80 CDV and an '80 FWB and both would run out of breath at anything more than moderate highway speeds. But that's an easily correctable situation, just a few simple hot rod tricks. Had I kept the Brougham, I would've put a mild street performance cam in it and that would be that!

creeker
01-09-11, 10:57 PM
I agree. I had an '80 CDV and an '80 FWB and both would run out of breath at anything more than moderate highway speeds. But that's an easily correctable situation, just a few simple hot rod tricks. Had I kept the Brougham, I would've put a mild street performance cam in it and that would be that!


I think if I take anymore big trips I'll use my 97 sts.

stephen ferman
05-28-11, 03:35 AM
Hey, my name is Nick and this is my first post. I'm sure there is a few posts about my question but what are some gains I can get out of my 1980 Cadillac Fleetwood with a 368 in it? Not looking to build alot of hp....example 400, but I would like some torque. Is it worth putting money into? Are the 80's 368 interchangable with the 472/500 parts? can i bore/stroke it to one of these sizes? The motor has 218,900 kms on it ao I was thinking of takin er apart and reseal it, but a 472 would be mint. please let me know, thank you
Performance parts of america has aftermarket performance manifolds and cams for that engine. the cam base circle is smaller so you will need there adj pushrods they have a slew of peformance parts for it