Input on '71 400 Rebuild
 

Two weeks ago I purchased another numbers matching basket case 71, tropical lime green, white vinyl top, white interior 400th trans. The original engine has been in pieces since 2000 so I swapped in a running 73 400 I have to get it on the road temporarily while the original engine is rebuilt. It is finally a running/driving car for the first time in over 20 years.

I would like to send the original engine out for a rebuild from a reputable shop as I would like to keep this one numbers matching. I am a hp junky and most of my other vehicles exceed 500 whp but my goal for this one is to keep it close to 400 whp. I am unfamiliar with the 96 heads and am curious if they can be hogged out to support that number. I am also open to build suggestions for a streetable build path for the engine as well as reputable builders for this engine in the Midwest (I am in Missouri).

TIA

I’m getting an “honest” 370-380 from mine.
I’m sure I’ll forget something, but basically-
Crower 60242 cam
Original Intake gasket matched
96 heads cleaned up and lightly ported
Ultralight rods
Flat top pistons
Block zero decked
.027 Cometic head gaskets ,CR is at 9.6:1
Original Q-jet
Original distributor recurved
Oversized RARE manifolds and mandrel bent down pipes
RobbMc 550 fuel pump

Track times are in my signature. That’s granny shifting with my original Muncie
Honestly, if I were to do it all over again, I would have just stroked it. :)

That is one gorgeous 71. Luv the color combo! Happy to see you're keeping it and treating it right.

I won't offer much advice on the build, but just to say your goals are well within reach. Good luck with the build, and thanks for sharing!

:)

I think you could easily reach your goals by installing a stroker kit to make it 461, and still keeping the stock appearance. Butler performance offers plenty of go fast goodies for Pontiacs and also specialize in Pontiac rebuilds. I would post this topic in the "Street " section, you will get a much larger response. Good luck with your build.

Love the color combo! I was inquiring about that car when I saw it for sale, just a little late to the party.

If I were to do mine over again, I agree, I would have just stroked it.

Streetable means diff things to diff people.A 500HP 400 IMO will be a nasty drive N/A 400 engine.With a stroker kit not so bad.Its getting harder to find people to port iron heads.Look for a 260 CFM port job at 600 will get you there IMO.Good luck with your project.Tom

I have seen that many times a build is done and the rest of the components do not match making it a good build that is not compatable with the rest of the project. What is the thing that you want to match the build to and that will determine the rest.
Examples are:
Transmission (auto, over drive, manual) Rear gears and tire size, head and compression, specific intake or induction, A/C or power brakes, use of vehicle for cruising or high performance . This information will then help determine the cam profiles, pistons, and supporting components. Avoid mismatching components and the project will become less expensive and frustrating.

I did this starting with wanting 3.08 rear gears, stroked 400, Edelbrock heads, TH-400 and street performance.
This helped with Piston (Compression), cam and stall converter decisions. I have plenty of vaccuum but installed a Hydroboost for brakes just because I wanted it not a need. Also Factory Air with Sanden compressor. I wanted a factory look so I used a needle scaler on the front of the heads and painted pontiac blue (Acrylic Enamel) and it looks pretty close to stock with factory valve covers.
The does not make my build correct, just the one that works very well for me and my application. A significant amount of time and money were saved by not haviing to redo anything or make changes due to a mismatch of the components and cam grind.
Paul