[GTOKIDRH]

Originally Posted by Formulas

you know what they say theres no replacement for displacement so why even fool with a 400 anyways

You are correct in a perfect world and deep pockets.


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[25stevem]

Formuals, did you read post number 78?
Dennis is talking about a .040” over 400!

In regards to the statement’ there’s no replacement for displacement “ in the racing world there is, and it’s called high rpm.

[389]

Change the carb to the quadtrjet. Put a 2" exhaust system with no X or H pipe. Use a pair a Dynomax Super Turbos.

Keep the rear end, it will work perfectly with the TH400.

You want an engine that runs on 87 octane. Keep the compression at 8.5 to 9. One thing the seventies taught us was running compression in the 10s 0r 11s isn't needed for very strong street performance. Keep the ports on the heads as close to stock as possible for good velocity.

Don't make the age-old mistake of using drag racing components on a street car. They are two completely different things. The Pontiac 068 cam is an excellent street cam so is the Summit 2801. You want bottom end power. This and the 2.56 rear end really works well with a street converter and will get the stator multiplying tork...

I remember this one article they did back in the eighties. They took a stock Pontiac 400 from a 1974 station wagon in a junk yard and put it in a 65 Le Mans. Replaced the points, cap, rotor and wires. Cleaned up the Quadrajet, Put some cheap 10W30 oil with a new filter in it and off they went to the drags. They got the lemans into very low 12s. They said with a little more screwdriver tuning they could of been into the 11s with ease.

[android 211]

I actually did that on a 350 Firebird. At 3000 the power simply flattened out and there was no real improvement at all. I then swapped the stock 2bbl cam for a '067' factory stock GTO cam and there was a huge increase in power.
It would hit 90 passing trucks on the highway. I was interested in getting the best possible mpg out of it as my old man despised V8 cars as gas hogs, he was very stingy. I succeeded in getting over 21 mpg out of it many times. That was after some used headers, duals and a cold air duct to the air cleaner. It had 2.73s out back.