400 engine swap.

[Madghost]

I just purchased a POS '85 TA carbed 305 and am in the process of restoring it. I dont want to keep the 5.0 as it would simply take far too much time and $$$ to make resonably fast and I have come across a 78 TA 400 that I figured would yield a good base platform.

Now origionally I was going to simply swap the motor but then was informed by someone that the bellhousing of my 700r would not fit, so I can either use the th350 presently attached to the new engine or use some type of adapter. In both cases I would like to know if there will be any unseen difficulties ie: "the th350 shifter would be in the wrong spot", or "the output shaft will not match up to the propellor shaft", or "hey they dont make an adapter that will do that" In which case I may just look for a 350.

Thanks for any input. :)

[tom3]

Having the complete car for the swap I'd think you should have no problems. The frame mounts will probably need swapped, and that can be a chore. If it were me I'd be looking for a 350 Chevy engine to swap, bolt in deal and parts are easy to find, and cheaper than the Poncho stuff.

[Nate Dog 69]

Transdapt (sp ?) makes adapters that go either way for chevy & BOP engines/trannies. Indian adventures I bellive already makes a kit for swapping in Pure POncho Power into thirdgens. ALso try Ames & maybe also year1. Kits are there, and I have seen pics of this swap done before.

[Madghost]

Thanks for the reply, but why would the frame mounts come into play? I was informed that the 305 and 400sb was essentially the same engine minus cosmetics, displacement and cpu.

Sorry for my dumbassery but I have just come over from the dark side of tuning imports (racers not ricers), and am finding it a little hard to track down specific info involving engine swapping. I am used to swaps such as the toyota 7mgte to 1jzgte so I know how big of a pita it can be sometimes. However I AM determined to turn this car into a unique and powerful ride.

I was just under the assumption that most GM componetry was direct-swap, but i'll get ahold of indian adventures and see what they offer.

THX

[tom3]

Don't think I've seen a 78 Firebird with a 400 small block Chevy engine stock. If this is for sure a Chevy engine the swap is a near bolt in.

[Madghost]

Is the stock 6.6L not a 400 small block????

if its a BB I have been grossly mislead and feel like a real shithead right now :(

[88406vette]

Originally posted by Madghost
Is the stock 6.6L not a 400 small block????

if its a BB I have been grossly mislead and feel like a real shithead right now :( the 6.6L are small blocks but they are diff than the Chevy sb 400's. That's what I've been told.

[BirdofFireBOB]

Swapping the 400 Pontiac is not for the faint hearted,, A 400SBC is just bolts & blood!

[nightrider]

the 400 in pontiacs are pontiac motors. its not he same as a chevy 400.

the swap isn't that hard either. there is a post at the top of engine swaps on TGO right now that has a 455 swapped in...a 400 and a 455 are the same on the outside so you can just do whatever he did.

and a 200 4R from a buick olds orpontiac would replace the 700R4 no problem and the tranny would be cheaper than buying an adapter.

[Madghost]

would that be any different than using the TH350 presently attached to the engine??

[MagRockwilder]

You CAN drop in a Pontiac 400, but it's pretty pointless considering you can build a SBC that will rape it for half the cost.

If you DO decide to build one, and you want an OD tranny, go with a 2004r with the BOP bellhousing. They can be modified to handle umpteen HP.

[Madghost]

Look I got the motor+tranny for 500 bucks with less than 30k on it, I will obviously be installing and running the motor to make sure it will deliver what I want before dropping an few grand in overhauling the engine and adding extra frame bracing. the key here is just making sure that the swap can be done without completly re-designing the front end.

I am a sucker for nostalgia, and think having a true pontiac motor in an 3rd gen will be pretty cool, I really have no plans on taking her past 450 or so hp so whats the big diff. on heads, crank, pistons intake etc. Especially when the extra effort will yield a fairly unique car with a cool shaker/GTA hood ;)

PS. I really prefer to do things that are hard because they are just that, it would be simpler to go out and spend 6k or a done up 383 and drop her in overnight. To me though it just would'nt be the same. I live for the process not the result.

[MagRockwilder]

Sheeit... $6k on a 383? I don't know where you're shoppin'. I've built 500hp SBC's for $2k.

[Madghost]

I am shopping right here, with the cdn ex. rate and shipping I am accually looking at more like 8k.

http://www.edelbrock.com/automotive/crate951.html

[MagRockwilder]

Crate motors suck.

[nightrider]

Originally posted by MagRockwilder
Crate motors suck.

uh huh

[Nate Dog 69]

Originally posted by MagRockwilder
You CAN drop in a Pontiac 400, but it's pretty pointless considering you can build a SBC that will rape it for half the cost.

If you DO decide to build one, and you want an OD tranny, go with a 2004r with the BOP bellhousing. They can be modified to handle umpteen HP.

This person has never priced parts for a 400, or just has a pretty deep resentment against it for some reason.