[Old-Dbls]

This original 72 BB 402 Sprint has been my daily driver for the past 10 years, and time has come to
breathe some new fire into the old girl... I would like to liven-up the stock engine, and if necessary
rebuild the 116K motor.. Don't need a radical 10-sec 1/4-miler, just want this 402 to perform better
on the street and put a smile on my face when it eats the occasional Ford between street lights...
Only upgrade thus far is an HEI, I'm now looking for more "402-Performance".... Suggestions?

(Best 402 Wake-Up Recipe?) ..... Thanks for your help...

 

[1969 El Camino Dan]

Consider new higher compression pistons, a stronger cam and if the heads need freshening, perhaps some bigger valves with roller rockers.

GM dropped the compression by at least 2 points to comply with the gov't mandates. Now's the time to bring it back up to real spec.


Dan

 

[kettbo]

You could treat your Elky to some closed chamber heads to raise the CR if you can re-use the pistons. If needing new pistons, get some bigger domes to raise the CR just a tad.
Crane/Summit 226*/.533" 108 LSA cam
or maybe better, the 228*/.544/112 LSA cam,
a 60203 or 60203 Voodoo
mild converter

 

[animal69]

My '72 402 has a Comp XE262H-10 cam in it. I was told that this is about as big as you can go without changing the stock convertor. It made a big difference but changing from 2.56 rear gear to a 3.42 really woke it up and made it more enjoyable to drive.

 

[79943]

i agree with some of the other posters. a little gear and a little compression can work wonders on a stock '72. as a general rule if you sweeten the compression, do the same to the cam timing. and depending on how far you reach, the exhaust, via headers, should be on the table also. then that puts the intake in play...high rise, aluminum...which in turn leads to carbeuration, you get the picture .

 

[Alan F]

Nice Sprint, I like it.

I had a '72 U code Sprint, and a '71 Custom El Camino that came from the factory with LS3. The former had a firebreathing 454 and would really move out if it wasn't blistering the tires. The latter had its original 402 warmed over. A little cam, blueprinted carb & distrib. The biggest thing that woke them both up was rear gears.

The '71 was a very nice driving package. It had a 3.31 in it and I changed it to a 2.56 to keep the other rear. The gear change killed its performance.

I currently have a '71 SS 454 that I purposely kept very close to stock. I wanted something peppy but not a drag car. I wanted to run regular fuel, etc. With 3.31 gears and 245/15 tires is just a little too many RPM for my taste at highway speed. If I had one, I would try a 3.08. Alternately I have thought about changing the transmission to a 200R4 mainly to optimize fuel economy. It will squeak out ~12MPG on a good run but normally in the mid-high 10's. I'd like to get about 16-18 and think it would with a different transmission.

So if I had your car and it's a regular to daily driver, my personal opinion is keep the engine very mild. You have enough to work with without getting in to high compression big cams, intakes, carbs, etc.

Your mileage may vary!

 

[animal69]

I guess I should have added that with the 3.42 gear I'm running a 29" tire in the rear.