Will a 500CID Cadillac engine bolt up?

Hey guys,
Ran across this list on the web of engine weights and physical sizes. Very interesting info for motorheads. Sorry if already posted.
http://www.35pickup.com/mulligan/weight.txt

I note that the 500 Caddy weighs in at 595lbs
the big block 454 Chevy weighs in at 675lbs
and the Buick V6 odd-fire 225 weighs in at 414lbs

 

Hey I just wanted to say Hi! I am building a Jeep/Chevy thingy and had a question for the th400 guys.

I have a 225/th400/20 combo out of a 71 Jeepster that is going in my project rig. The 225 is taking a dirt nap, and being replaced with a 10:1 1970 Caddy 472. After searching the site and the net I still have a few questions.

The th400 I have is the one with the BOP adapter, this should bolt to the Caddy no problem, but when it comes to the converter and flexplate is where I'm fuzzy. Will the stock Jeepster converter bolt to the Caddy flexplate? I do not yet have the 225/400 seperated.

I've been hearing the word NAILHEAD mentioned, does the NH th400 (which is what the 70 th400 would be right?) have a shorter case which is why the adapter does not affect the distance between converter to flexplate?

I just want to be DOBA (dead on balls accurate) that combo won't thrust the engine or tranny.

I KNOW someone on this site has done the swap, hook me up!

Here's the project:

1987 YJ frame
1939 Chevy cab
???? Jeep grille
Sterling 10.25 rear axle on 40's
D44 frt axle on 33's (offset gearing)

 

Yeah, I just painted them. Probably won't last too long when aired down.

 

I see no reason why you'd have a problem, converters were the one thing that remained the same, relatively speaking. I'm running a 350 Buick in my snowplow Jeepster. Liking the looks of your ?Jeep? . And yes, the Nailhead has a shorter case. The tranny would have bolted directly to the engine without the adapter/spacer.

 

Just a few details... The earlier Buicks engines, known as nailheads because of the valve locations, have a shoulder on the block that sticks out to meet the transmission. That's why the nailhead case is shorter, and the adapter fits in between the shorter case and the BOP engines.

I understand there's a cast iron adapter on the end of the Buick crankshaft that supports the front of the torque converter. I think it will fit a Cadillac with no mods, but not 100% sure. That's the only possible hangup that I can think of.

I suggest you ask your question on www.ifsja.org/forums - there are some guys over there that have done this swap, and they would know more about the details.

 

You're thinking of the AMC 304/360, none on Buick.

 

The auto parts store I used to use alot had a guy that worked there with a chevy luv that he had put a 500 in.. where there's a will there's a way ( even if it does mean removing the firewall and having the tranny take up half the cab...)

 

hell, that needs an early hemi

 

Well ok then. :tea:

 

About 10-12 years ago I knew a guy in El Paso who had a CJ-5 with a 500 Caddy in it,,,,,,it absolutely TORE UP the sand dunes,, had power to spare and ran like a scalded ape. Kind of spooky on the pavement thought, especially given the CJ-5's short wheelbase and over 5 inches of SOA lift.

I'd say go for it just to get as far away from the "Red TJ Syndrome" as possible.

 

There's a bunch of Youtube videos of this guy's CJ7 with a 572. Slight overkill. I especially like the one of him blowing the doors off a Ferrari in a street race. http://www.youtube.com/watch?v=2TxtfXhfT2g&feature=related

 

It would be un-American NOT to put a 500ci engine in a jeep.

 

Well it has been a while since I posted on here, just got around to trying to fit the engine to the th400......it will not work. The caddy flex plate is a larger in diameter, and will not fit within the cast iron adapter. I thought about seeing if there is a smaller diameter flex plate availible, but then I may run into starter issues....round and round we go!

So I guess my next option is to put the tail shaft on the stock Caddy transmission.

 

Isn't the stock Cad tranny a Turbo 400 also?

 

It's my understanding the stock tranny in the Caddy was a TH425. Slightly higher torque rating was all that I thought was different.

 

I just helped a buddy of mine install a 472 into his cj7 a couple of years ago. The 472/500 is an awesome engine. I am not sure what is the best option on the transmission but if you can find the smaller ring gear flexplate you should be able to find a starter. GM was pretty good about starter interchangeability between those classic V8s. The big difference is if they are on the left or right side. Like I believe chevy and Buick are on the right side and I believe Olds and pontiac are on the left. I can't remember which side the Caddy is. The starters are very similar. The starters for the small ring gear have both bolts inline and the large ring gear have the two bolts staggered with one long and one short. The nose pieces are interchangeable. So a different starter could be an option. Now on the tranny side. I am pretty sure the caddy TH400 or 425 is probably a long shaft. You will need a short shaft tranny or you will have to get the tranny converted to a short shaft. For my friends Jeep I gave him a spare TH400 I had out of a 70 GS455 Buick. We just pulled the tailshaft off and installed the Dana 20 and adapter that was on the back of the AMC era Wagoneer TH400 he had. It bolted up no sweat. That may be an option for you especially if you happen to have a short shaft tranny in the Caddy.
I will tell you that my buddy used Sanderson Headers and they are quite nice. He was running an Edelbrock performer intake along with a Comp 260H cam. I wish I could tell you how well it all runs but he is still building this Jeep and progress has been very slow. He had a bigtime setback when we had a early cold snap last winter, it got well below freezing in his shop only to freeze and crack his Caddy block badly, as he had been running it in the chassis without antifreeze. He has been so devastated that he has had a hard time motivating himself to get back putting the project back on track. I need to help him track down another block or engine to get it going again. The other thing I remember for troubles as far as the install goes is his engine was a front sump engine and he really needs a rear sump pan which I believe only came on the 500 in the front drive car.
I hope some of that info helps you out. Good luck getting it together. It should be fun.
Greg

 

I forgot to address one other thing in your earlier post. That is a way cool rig you have there by the way. I love it. Anyway first off, a true Nailhead buick TH400 will not work at all. A Nailhead version of the TH400 came in 63/64/65 behind Buick Nailhead 401s and 425s. It has a round bellhousing bolt pattern and is really a early predecessor to the later common TH400 built for the next 30 + years. Some people call the 300 and 340 as well as the 225s in the Nailhead family as they had similar Valve covers but they have nearly nothing in common. So there is some misconceptions there.
Greg

 

Greg thanks for your reply. The starter is on the right side on the caddy block. Maybe I can find a smaller flexplate, as that would be the best deal, since this Jeepster nailhead transmission is only 4 yrs old and has next to no miles on it. Would the tailshaft from the jeepster 400 fit in the caddy longshaft tranny? The caddy tranny looks like it is a long shaft style because it is...well... long. The tail housing looks like it is 10+ in long. It's not near me at the moment to measure for sure. I have not messed with many autos, have rebuilt several t-5's, 3spds, and t-cases but am a bit lost on the auto stuff.

The pan is not an issue in my situation. I have an Eldo pan, that I'm saving, and used my Sedan Deville pan instead. Seemed a waste to use the good pan if not needed.

That totally sucks about your buddies 500. I feel for him.

Here's a pic or 2 of the project.

 

You definitely have a long shaft tranny. Short shafts are more common and have a stubby short end about 5" or 6" long. You could pull apart the Jeepster tranny and rob the shorter shaft out of it and install it into the caddy tranny. You could also install many of the other guts of it while you are at it as well. You might as well stick in the clutchpacks and bands out of there while you are at it. Just pick the best parts from each of them and put it back together. If you happen to have a TH425 behind the caddy (which I doubt) you should use the heavier planetary and drum out of it. You could also just get a budget rebuild done on the Caddy tranny and get them to swap to a short output shaft. You will not need the tailstock housing with the transfer case. You could also just find a complete short shaft BOP TH400 and bolt your transfer case up to it. I have seen complete trannys go for $50 to $100 around here. Add a B&M shift kit and your are rockin'. I am pretty sure your Dana 20 will have an adapter and an input that will slide right on the back of a regular short shaft TH400 from a car. It should have a fairly fine spline shaft input (28/30/32 ???) on the Dana 20 like my buddy had. It worked out great for him. I hope that helps you out.
Greg