Im wondering what everyone's opinion is on the Pontiac 400 motor. Is it a solid block and if built correct have a decent power range? Is it a waste of money and effort to put into a '79 camaro? What would be needed for the swap, is it bolt in or no? Also a Turbo 400 bolted up to it, is this the same as the Chevy turbo 400? Just everyone shoot stuff out about this motor for me please, im looking at a 79 Trans Am with a 400 in it and jsut want the motor and tranny so im seeing if its worth it.

I can’t comment on the motor, but the trans is a little different from the Chevy version. There is a bolt pattern for mounting to BOP (Buick, Oldsmobile, Pontiac) motors that is different from a Chevy, but can be used with an adaptor plate from someone like Transdapt. I believe that the tail shaft is longer, which would necessitate a shorter drive shaft than a Chevy short tail 400. If you would need a new drive shaft anyway, this would not present a problem. There is no real difference internally, just the physical differences.

The Pontiac 400 is a good engine, but generally isn't an inexpensive engine to rebuild compared to a Chevrolet of comparable power output. Bracketry, plumbing and wiring is all different compared to Chev as well.

did one a few years ago for a buddy of mine. the stock cast (not forged) rods aren't really good to trust above 6000 or so. under that would be ok though. i'd limit it to that with stock rods. unless you can find some of the old fire truck 428 rods that were forged. otherwise,, there are some aftermarket choices that are good. found some "Legend" brand 4340 forged H-beams for 274$ on ebay with bushed and floated pin ends, and 7/16" ARP capscrews,, fully cnc machined.

the stock heads won't give very much compression. finding domes for them cam be pretty tasking. i've heard they're out there,, but,, time for them to tool up to make a single replacement can be a pain if you need a replacement single piston.

heads like eddy rpms with small chambers would be the way to go. can get to 10.0:1 alot easier with the flat tops. my buddy has a new set of the eddy rpm's on my garage floor now. the older poncho closed chamber heads are getting harder to find,, then after finding and buying them,, end up modifying for bigger valves and such,, like with a chevy,, it's easier to get to a better port design with smaller chambers,, and aluminum to save the weight,, for about the same cash outlay. fairly strong engines though,, great torque from the 400's. hope it helps. andy

My first car was a 69 Catalina with a 400 Pontiac with a 2bbl on top and a single 2-1/4" exhaust. I did come from the factory with the high compression engine option (10.5:1) but was like a fat man breathing through a straw. Without ever touching the internals I got that 4000 lb. boat to run high 14s.

First I converted it to a QJet 4bbl, then I cobbled together a tripower setup (3 2bbls with progressive linkage).

Ditched the single exhaust and put on the factory option dual exhaust. Then upgraded the mufflers. Then ditched the manifolds and installed headers.

Ignition was stock points at first and then an HEI conversion.

Once it was dialed in it would run 14.7-14.8s all day long- not bad for the weight, stock converter and the 2.73 rear gears. It was a torque monster. I don't think I ever spun it past 5500.

With good heads, a modest cam and pushing a lighter car with appropriate stall and gearing I can imagine it could be made to go quite fast, even with the factory cast crank and rods. Agreed, high RPMs would probably expose the weakness of a stock bottom end. Also agreed, Pontiacs come with flattops pistons, pretty much end of story. The factory got the different compression ratios almost exclusively by changing the size of the combustion chambers in the heads. There is very little available from the aftermarket for reasonable money other than flattops.

Talk to Ken, he's still got that carbed LT1 setup sitting in his garage.

Talk to Ken, he's still got that carbed LT1 setup sitting in his garage.

WEll what im looking at is a 79 TA with a 400/400 set up with about 100miles on it. I 'm contemplating buying the whole car taking the motor and tranny and parting the rest out. Im not sure though.

The Pontiac engines make great torque, but are larger, heavier, and more expensive to build. They also use different (pre-existing) holes in the subframe.
100 miles sure is new, should be in great shape.

WEll what im looking at is a 79 TA with a 400/400 set up with about 100miles on it. I 'm contemplating buying the whole car taking the motor and tranny and parting the rest out. Im not sure though.

Careful.... is it a 400 Pontiac or 403 Olds? If stock, the '79s usually had the 403. Very few got a 400 - only those with the 4-spd option, which wasn't many. Autos all got the 403 Olds.

Careful.... is it a 400 Pontiac or 403 Olds? If stock, the '79s usually had the 403. Very few got a 400 - only those with the 4-spd option, which wasn't many. Autos all got the 403 Olds.

Not the original motor. It is a 77 block i believe which was the last year for the 400 in the TA if i remember correctly.

7.6 to 1 CR!!

So go from there!!

UP the COMPRESSION, compression, compression!!!!!

Oh, did I say up the compression??

Onna the mag's recently did a last year 455 buildup and it is just about perfect for you to study!!

Same deal, just a bigger engine is all so it fits!!

pdq67

The engine that made its fairwell in the 77 T/A was the 455. The 400 Poncho was the norm for all 78 cars. In 79 not all auto cars were 403 olds. The way to tell if the car has the original paint and decals is by the shaker decals! The olds powered cars had 6.6 TA decals while the Poncho powered cars had 6.6 litre decals. The 79 was the 10th anniversery year and there were a limited # of special edition cars that were 400 Poncho 4 speed only two tone silver and gray. These cars are where the legend of the 400 poncho only came in 4 speed cars.
The real way to tell is look at the engine, does the oil go in the valve cover or in a stand tube at the front of the engine? In the V/C it's a Poncho, In the tube up front it's an Olds.
The 403 olds is a weak, very weak, block! The main webs have windows between the mains and the cam bore on 1 thru 4 mains! I have seen stock 403's rip the main webs, crank and pan out!
The 400 poncho is better than the olds but no where as durable as a Chevy.
Don't bother wasting time looking for the 421/428 HO factory forged rods. They are barely stronger/durable than the later cast rods! Neither will last above 6000 for any length of time with ARP bolts, polished and profiled, shot peened!
In other words if it ain't a pontiac car don't put a PONCHO engine it!

400 Ponchos were OK engines. Some were pretty bad-ass from the factory. Not that year though. A real dog if it's stock. I had a 76 TA with a 400, one of the slowest cars I've ever owned. All show, no go.

If it were me I'd sell that engine to somebody who's looking for that year block. Should be worth a nice piece of change. Post it at TAC. Then use the money to buy a Chevy engine.

The engine that made its fairwell in the 77 T/A was the 455. The 400 Poncho was the norm for all 78 cars. In 79 not all auto cars were 403 olds. The way to tell if the car has the original paint and decals is by the shaker decals! The olds powered cars had 6.6 TA decals while the Poncho powered cars had 6.6 litre decals.

Thats right, I forgot about that... I think you might have it backwards though. "6.6 Liter" = 403 Olds... "6.6 T/A" = 400 Pontiac.

http://www.transamcountry.com try this it will tell you what you need to know ,, have 3 400 2 400 trans out of birds one is a R/A 3 also have cherry 79 body but not a T/M dont know what I will do with them also have a 71 formal with a SD 455 it is next after the 71 Z

old chevys never die they just go faster !!!!

Thats right, I forgot about that... I think you might have it backwards though. "6.6 Liter" = 403 Olds... "6.6 T/A" = 400 Pontiac.

Wasn't for sure from memory so I stopped by a friends tonight who has a 10th ann car all original with just over 17k miles. Lucky b@stards dad bought it brand new drove it for 2 years and parked it in a heated garage on jack stands! It has the 6.6 litre on the shaker. He also confirmed that all 79 403 cars had the 6.6 T/A shaker decals and the 400 poncho cars were 6.6 litre decaled shakers.

Fwiw, and I may be off on years so check me!!

My second B-i-L had a '74 or so(??) 455HO in a G/P that my wife had to drive years ago for a short period of time!!

She said that when going from one side of town to the other back then, she could actually watch the gas gauge needle fall! Gas mileage was that bad in the pig!! BEAUTIFUL CAR otherwise tho!!

pdq67

this is my friends 400+cid it resides in real #s matching 70ta ,,,,pontiacs make crasy tourq,,,, this is a pic of his motor i took this morning ...

http://img146.imageshack.us/img146/9151/1001510rw5.jpg

http://img19.imageshack.us/img19/5357/1001505qp4.jpg

this is my friends 400+cid it resides in real #s matching 70ta ,,,,pontiacs make crasy tourq,,,, this is a pic of his motor i took this morning ...


Wow, white and blue 70! Very cool. I've always wanted one like that. Got any more pics?

Did the 67 come with a 400? I just bought one with the 400 emblems on the hood and the tach on the hood as well.

The Olds 403's look weak but they aren't THAT weak. I have a friend who runs the Olds 403s exclusively in G/SA and K/SA. He (and his wife) have won several NHRA National records with these cars. He doesn't have issues with the mains in them and he is spinning them 6000+ and making enough HP to propel some heavy cars (A and B body) to low-mid 11's.

Wow, white and blue 70! Very cool. I've always wanted one like that. Got any more pics?

here is his 69 lemans next to the 70 ta he didnt take them out yesterday weather was so,so ill take better1s next time there out ,,,the lemans just got a fresh bullet in her it pounds pretty good,,,http://img522.imageshack.us/img522/8452/1001515hw8.jpg

lemans has a poke and stroked 400 ,,,,next year it gets spray....
http://img530.imageshack.us/img530/6344/1001511ho0.jpg
http://img262.imageshack.us/img262/9996/1001514na3.jpg
cant see to goog the lemans has some big meats in the a$$...

TA.S interior..............
http://img503.imageshack.us/img503/1024/1001508eh5.jpg
lemans interior..
http://img503.imageshack.us/img503/3963/1001509xb6.jpg

1976 was the last year for 455s not 77. 77 had a 180 and a 200 hp 400, the 200 hp has the "TA 6.6". 1978 they added dual resonators and got the TA 6.6 up to 220 hp. The TA 6.6 motors had 6X heads like the others but the smaller 350 ci combustion chambers which were 8.2:1 compression. You can tell the difference by a -4 for them on one of the bosses by the valve covers vs a -8 for the "plain" 400. The later blocks are weaker for a real heavy hitter build but I've got one I've raced making 400 hp for 10 years.

Less expensive forged rod options are numerous now, forged cranks have just come out so building a serious Pontiac has come down alot in price from just 10 years ago. Edelbrock makes soem great heads. Dave Bisshop at SD Performance has just come up with CNC programs for some of the iron heads to be ported. Building a 12 second Pontiac can be done fairly easily nowadays.

YES!!

'67's came w/ 400's b/c my big headed B-i-L had one! Olive drab colored w/ white interior, no console 4-speed and all...

Funny thing about it was that it's Q-Jet was limited so that it's back barrels wouldn't open up all the way b/c Pontiac didn't want the 'Bird to out power the Goat back then!!

I think that maybe the 'Bird's Q-Jet intake's back barrels may NOT have been fully round????

pdq67