what are the specs on these motors stock? im going to be buying a 400 small block off of a freinds grandfather, its been in his garage and needs to be rebuilt. but the thing is.. i wouldnt have too much money to do it... so if i rebuild it to some stock specs and upgraded later, what kinda power would i be looking at?

 

or more specifically, like cam, compression, and head specs would be real cool, something for me to work off of.

 

The '70 Impala 400 2bbl I had was rated at 265 HP. That's a gross flywheel rating, not the net we're using now.

Compression was on the order of 9:1. Heads were terrible for performance. Cam was intended for smooth idle and low rpm torque. I put a q-jet and dual exhaust on mine, hardly made any difference.

The shortblock is a great foundation for a performance engine. Everything else is boat anchor material - cam, heads, intake, exhaust, etc.

 

basically in stock form there dogs, like stated the heads are junk and the cam is way too small, but some new heads, a nice cam and other bolt ons and 400's are monsters

 

well wouldnt the one's put in 1970 camaro's be a little quicker than the one in a 70 impala?

 

GM never used a 400 small block in any Camaro. Starting in 1970 Chevy used a 402 big block in the Camaro, however it was badged 396.

 

More commonly, 400's were used in station wagons, pickup trucks and vans. The trucks stopped getting them in 1979. They were never put into any sort of performance car since they weren't built for performance. No 400's came with 4BBL. They were all 2BBL

 

the car 400's were pretty much 2bbl the truck 400's are pretty much all 4bbl engines

 

Strange....the one I pulled from a 78 Blazer had a Q-jet on it

Pete

 

I was too lazy to correct it. Look at the next message. 400's in trucks had q-jets but are still not performance engines.

 

400 Pontiac engines in late 70's TA's didn't have 4 bbl's? Seems odd, but I could be wrong.

 

theyre referring to the chevy 400...not a pontiac 400... the pontiac 400 is "big block" pontiac

400 chevy is a bored out/stroked whatever small block 350 i believe

 

The small Chevy 400 is a siamesed-cast cylinder, 4.125" bore, 3.75" stroke, increased journal size, shorter rod, externally balanced version of the SBC. It shares external dimensions and bolt patterns with the 350 (and the smaller versions, of course), little else.

Cams will fit, lifters/pushrods/rockers are the same, intakes will bolt on - that sort of thing. But, there are a lot of little details that are different.

 

oic, my bad. I'd prefer the Pont 400 myself!

 

mmmm... -drools-
1970 fornula 400 ram air III 4 speed...mmmm...400

 

they are also hard to come by these days. I was able to find two of them for 50 bucks a piece. and always looking for more.

they are not bad blocks, but in stock form they suck. but being able to get big block power out of small block size.

but i do like the big main journals, that can handle a lot of stress.