Help with engine swap

I have a 66 pontiac tempest that needs a new heart. I have a Oldsmobile 455 engine that I want to put in it. Will this be easy to just drop in the pontiac or will I have to dosome modifications to make the engine fit?

You'll have to check the motor mount spacing and location. The olds 350 and 455 mounts are the same but between pontiac and olds there may be a difference. There also might be a difference in the distributors. The olds had the distributor going through the back end of the intake, while most (if not all) others had them in the back of the block. That is about all I can think of at the moment. Sorry I couldn't help more

:grinyes: Thanks for the input. Some good places to start. Appreciate your help.

I wish I could help more but I do not have any experience with Buick motors. If someone that knows lots of details about Buick motors then we could chat about the differences. By the way what size motor are you pulling from the tempest?

I don't have any experience with Buick or Olds. I've always had Pontiacs with a few chevs thrown in, so this is new territory for me.
I've been looking locally for a bb Pontiac motor for a couple of years, and it seems that by the time I make the call about them they're gone. So I found this Olds motor and tranny, got it for an awesome price, thinking that I could put in in the tempest. But just not really sure of the fit. I think it will work ok, just looking for a heads up.

The tempest was sittin in a farmers field and had seen it's better days. Got her for $200. Original motor was a 389, but it was long gone. Interior is toast and she was a little rusty in the normal spots. Quarters, around the lower rear window and the lower front window too. Had to replace some sheet metal on her, shaved her and now starting on the engine. I'm not going to clone her into a goat, for some reason that just doesn't seem right. She's going to be a one of a kind I think. But still have a long way to go. She got put to the side when the wife bought a 73 firebird. That one's almost done and now have some time to work on the 66.

Well you never know until you try. I'd say since it already had a big block just measure the location of the motor mounts. They could actually be a perfect fit. If you are going to pull the engine and tranny anyways, then just pull them now and get the tape measure out. Unless you can do it with the engine in the car.

Tempest1959,

You might wanna e-mail me or call around some more. Pontiac engines are plentiful. The Tempest had a 326 in it, BTW (no 389s except in GTO). We have one very happy customer running 10.20s with his '65 'pest (that's what the Chevy boys refer to him as). It's a 400 block, Eagle "kit", Iron d-port heads (extensively ported), TH400, 3.90 gears... The thing ROCKS!

Parts for Pontiacs are at an all-time high (availability). In the last five years, enough stuff has come to market to allow Pontiac to take its' rightful place in the GM performance "hierarchy" as no. 2, solidly in front of small block Chevy, right on the heels of BBC. You should see the Tiger! (new cylinder head, looks a BUNCH like "Big Chief") All we're really waiting on to retake top spot, is the availability of reasonably priced forged cranks. They're on the way!
Under 650 HP, stock blocks and cranks are fine. After that, you really need to step up to the modern parts if you want to stay both alive AND competitive.

As tough and powerful as stock Buick and Olds engines are, once the modifications start, they simply cannot "hang" with Chevy and Pontiac. That is, the engines don't respond as positively to performance mods as the Poncho and Chevys do. Of course, the small block crowd takes exception to this, but I submit: GTO did not get it's reputation from LOSING... Pontiacs really are a viable race engine, even 27 years after production ended.

Just offering up to date info!

Jim

Jim, Thanks for your input. Your absolutly right, the Tempest originally had a 326, but that was swapped out for a 389 sometime in the 80's. And that was sold out of the car about 15 years ago.

As far as getting a Pontiac motor to drop back in her, Man,that is what I'd rather do. I've always been a Pontiac motorhead and now that I look back I could just kick myself for getting rid of them. 66 LeMans, 65 GTO, 66 sprint with a tri power. Not to mention the old 55 Chev Bel Air and the 56 2 Dr. Sedan delivery.:banghead:

I've run across quite a few of the 389's and the 400's, but around here, Portland OR, the pre '72 455 Pontiacs rebuildables are gettin hard to find. Or at least I haven't had much luck. Been lurking around the wrecking yards and watching the local papers. I don't want one that's already built, I think half the fun is doing it yourself, you know exactly what your getting.

Still thinking of just building up the Olds and selling it at the Portland Swap Meet in April. Who knows maybe I'll get lucky and run across what I'm looking for.

Anyway thanks for the info.

Doug

400 blocks are the most desirable. Much stronger (physically) than 455. The current "rage" is to use the 400 and install the Eagle "stroker" kit, effectively giving you 455 power without the block.

You need a '67-'75 400 block. The pre-'70 models had only the two mounting holes on the side (will fit your car). The '70-'75 models have 5 holes, allowing them to be installed in both the earlier and later cars. 'Mid-'75 through '79 (last year of sale) have only 3 holes, and require an adapter to fit your car. There's little if any difference in strength between the early and mid models. The later are "light weight" castings, and are considered weaker.

What part of Portland? Mom and sisters live around there, as does youngest daughter. Most in Beaverton, but one in St. Helen's and another in "the city" (39th Av).

Jim

Hey, thanks, I didn't know that about the 400 being a stronger motor than the 455. That's kind of pushing me towards the 400 motor. Now those I've run across both in the paper and the wrecking yard. Of course the one's in the yard are usually in the safari wagaon or a bonneville. Do you think it would be worth gettin one of those and starting from there? Or try to find one from an A-body or F-body car? Those are a little tougher to find at a reasonable price.

I saw a built 400 at the swap meet last year. Man that was one nice motor. What a clean sweet sound it had. Can't telll you how bad I wanted that motor!

I'm acutally about 10 miles south of Oregon City, out in the country.