pontiac in a chevy?

[stepside-mitch]

I know this may seem pretty damn crazy but It just might work. I was thinking about a new engine for my stepper in the spring. I want something with a little oomph but different. At first i was thinking about a vintage 283 but i was talking with my uncle and we've come to the conclusion that a nice 400 pontiac would fit just right. His back yard is basically a pontiac junkyard and he has many go-fast goodies for it too. The engine was taken from a trans am and is backed by a t-10. With a little work that thing will go great in my truck. What do you guys think of that? Please keep the insults to a minimum I know this isn't what you all are into

[cjlinkster]

The Pontiac 400 is an excellent motor; there's nothing wrong with that selection! I would recommend replacing the cam with a something that would give you a little more torque (like a towing cam).

I'd say go for it....

What year TA is it coming out of? I owned a 1978 TA myself, and it was a California car. The 1978 ~ 1981 TA from California actually had the Olds 403 motors in them from the factory. Something to do about the emissions. IMHO the Olds 403 was a decent motor too; just not as powerful as a real Pontiac 400. In stock condition with over 100K miles, I could smoke the tires in every gear.

My TA actually seemed to get decent gas mileage; perhaps around 24 mpg or so..

[cjlinkster]

That is going to be cool! If he has the motor already, I say go for it.

[rwhit57]

Dollar for dollar you can build a SB Chevy motor that will do just as much or more than the Pontiac 400, but if you had a motor that was good and only needed say gaskets then the idea doesn't sound as crazy as some might think. I actually like the idea if you can do it without spending a bunch of money doing it cause if you ever get tired of it and decide to sell it, it's going to be a lot harder finding someone else that likes what you did.

[cjlinkster]

Originally Posted by rwhit57

Dollar for dollar you can build a SB Chevy motor that will do just as much or more than the Pontiac 400, but if you had a motor that was good and only needed say gaskets then the idea doesn't sound as crazy as some might think. I actually like the idea if you can do it without spending a bunch of money doing it cause if you ever get tired of it and decide to sell it, it's going to be a lot harder finding someone else that likes what you did.

If the time comes to sell the truck, just paint the engine black or chevy orange. Most guys under 35 wouldn't even notice that it wasn't a chevy 350.

Dollar for dollar a Pontiac will cost more to build up than a SB 350. But if the motor is from a 1974 TA, it should already have a decent cam, heads, carb, etc... After about 1974, the horse power ratings started decreasing until the late 80's.

A built-up Pontiac 400 is going to behave more like a BB 396.

[66-PMD-GMC]

Originally Posted by rwhit57

Dollar for dollar you can build a SB Chevy motor that will do just as much or more than the Pontiac 400, but if you had a motor that was good and only needed say gaskets then the idea doesn't sound as crazy as some might think. I actually like the idea if you can do it without spending a bunch of money doing it cause if you ever get tired of it and decide to sell it, it's going to be a lot harder finding someone else that likes what you did.

Not true..... you will spend more on a chevy 1st gen small block to equal the torque output of a stock Pontiac. I have 35 years of experiance in building both motors to make that claim.. Pontiacs make more torque than sbc... dollar for dollar.

[Firebirdjones]

Love the pontiacs, (grew up around them) and have had my share of birds (currently a 70 ram air III formy). Great engines that make grunt.

Actually should make an interesting engine for a truck. Like mentioned, grab the accessories to make the swap easier. Accessories on a pontiac are mounted opposite of the chevys, including the fuel pump and starter, so you may have to deal with moving wires and fuel lines to opposite sides of the engine.

For the record,,,the pontiac 400 was made up through 79 but was only available outside of California. California built/sold Pontiacs got the 403. The 4 speed super T-10 was also still available then only on the pontiac 400,,,,the 403's were auto's only.

[stepside-mitch]

This one came out of a '74. im not quite sure what year the t-10 came out of. These things are sweet little engines.

[cjlinkster]

I have always heard that with the pontiac engines that there is just the one block size and then they are bored to whatever displacement. So you could turn the 400 into a stroker or bore it out to be a 455.

Honestly though, a tuned 400 is going to be plenty for a truck.

[Liz]

go for it... we put one in my cutlass years ago when the 231 blew up. It rocked the 400...

[stepside-mitch]

The engine is actually in really nice shape. I dont see it needing too much work other than gaskets, maybe rings and bearings. It was mangafluxed about 10 years ago. I plan on dropping it in and driving the hell out of it

[gchemist]

Look for a 455 rocket!!

[78 Chevyrado]

Sounds good to me man, Git-R-Dun.

[raceman6135]

Grab all of the Pontiac accessory brackets, too. That is, if you want your alternator, power steering pump and air conditioning compressor to work

[Pop's C-10]

B/O/P engines have been going into squares for yea..i say do it

[cory d]

when i was in the local wrecking yard i was looking at a, early 70's pontiac and i was talking to my dad about getting a pontiac engine in my truck, i think it would be a neat suprise when people look under the hood

[Slonaker]

Years ago my Dad knew a guy with a Pontiac in a late 70s C10. He did it because the engine blew in his truck, and he had a Pontiac with a bad body and good engine. I think he said he used Grand Prix motor mounts, and I know he said it bolted in. I saw the engine in the truck, so I know he did do it, but I can't confirm how he did it.

All that said, I would like to have an Olds 455 in mine using the diesel motor mounts...

Slonaker

[lilpoindexter]

It would be cool!!! DO IT!!!

[sethv]

Crossbreeding vehicles is awesome! My friend has a 74 C10 with an Olds 350. Runs better than the old K10 I used to have (Had a Chevy 350)

[mustangt5]

My 79 stepside had the diesel engine in it and when it blew the turbo 400 that they had bolted up to the diesel had the same bolt pattern as the pontiac. So now it has a pontiac 400 in it.

[72lb4x4]

GMCs actually came with Pontiac V8s in the late 50s so its not totally unheard of. Go for it.
I tend to think Potiac engines have too few head bolts, but maybe the SBC just has too few...

[Palf70Step]

Originally Posted by stepside-mitch

I know this may seem pretty damn crazy but It just might work. I was thinking about a new engine for my stepper in the spring. I want something with a little oomph but different. At first i was thinking about a vintage 283 but i was talking with my uncle and we've come to the conclusion that a nice 400 pontiac would fit just right. His back yard is basically a pontiac junkyard and he has many go-fast goodies for it too. The engine was taken from a trans am and is backed by a t-10. With a little work that thing will go great in my truck. What do you guys think of that? Please keep the insults to a minimum I know this isn't what you all are into

If the engine is the original for that 74 TransAn, then it is just a corporate 305. Late 74 they started offering the 455 again, but only with an automatic.


I loved all my big block pontiacs. Like was mentioned, it is cheaper to Hot Rod a SB Chevy, but oh a BB Pontiac is sweet and well worth the effort to me.

[C-10 simplex]

Here's the link i found previously. Unfortunately, most of the pictures are gone, but the info is still pertinent. i believe firebird mounts were used:

http://forums.performanceyears.com/f...d.php?t=596830

What type of transmission do you have?


Pontiac simply rocks. If i was in the same situation however, i would just go chevy because it's just cheaper/easier/faster to get running. But i can certainly understand wanting to go pontiac.

[C-10 simplex]

Ooooh....found another one:

http://forums.performanceyears.com/f...d.php?t=647905

[406 Q-ship]

Originally Posted by Palf70Step

If the engine is the original for that 74 TransAn, then it is just a corporate 305. Late 74 they started offering the 455 again, but only with an automatic.


I loved all my big block pontiacs. Like was mentioned, it is cheaper to Hot Rod a SB Chevy, but oh a BB Pontiac is sweet and well worth the effort to me.

Incorrect.......305 did not come out until 1976 or 1977. They did not put any Chevys in Trans Ams until the late 1970's (1979 if memory serves). Oh ya I worked in a Pontiac Dealer in the mid 1980's and can tell you that the 455 was available with a 4 speed up till 1976 (had a customer with a 76 455 T/A T10 with T-tops).