Thread: What to do with a 402 Truck motor

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Hi Guys

Just joined - and you'll have to excuse my Big Block ignorance. I just bought a 67 Camaro convertible - it was a small block car per the Cowl tag - but has a 72 402 big block in it (TKX engine code) - a whopping 210 HP !!!

Eventually I'll probably build a small block for the car - but in the meantime I'd like to wake up the big block. I don't actually have the car yet - so all I have is the engine code - not the block or head casting numbers. So - it's possible that someone put some better heads or a cam in this thing, but I'm going to assume that it is just stock for now.

So - I'm thinking head, cam, intake, swap to wake it up - but I won't bother if the lower end is 8 to 1 compression or something... A little research tells me that Summit sells some cast iron rect port heads for about $700 each - and then I could do new dual plane aluminum manifold, and a hydraulic lifter cam that's not too radical - I really just want to make about 350-400 HP so I don't get embarrased by 5.0L mustangs... Whatever I do has to still fit under the RS/SS Hood. Car is a muncie 4 speed - rear end is probably the stock 3.31 as well. No interest in headers either - too much hassle for a street car.

Any suggustions guys? This is all assuming the lower end is healthy - if it isn't then it's time for a small block build I think.

Thanks in advance

Hi 67 Pacer,
Welcome to the madness. The 72 402 is actually a good engine with OK heads. They are oval port which is MUCH better than later year 454 peanut port heads. A good cam kit & intake & carb should do a good job waking it up. If you have a bigger budget then heads will help make more HP. I would do a mild rebuild and install a TKO-600 to make the biggest change that will help all around driveability like 1/4 times, cruising & better GAS MILEAGE!!!
If you need parts I can get a good combo that you'll love. Who knows, maybe an A/C unit will follow and it will become a daily driver.

it would not be hard to get 350to 400 hp that you can drive on the street.bbc i have used many HYD roller cams for the BBC . soild rollers for street /strip or just hi RPM s. you can buy a 454 crank and pistons to fit the small bore and 454 stroke pump up the CID . you can still get pistons for the 3.760 crank .stock rods rebuilt can take 450+hp along with any stock cranks steel or iron. with stock iron EX will hurt hp.with stock heads with some work you can get past 400 hp EZ

Thanks everyone - if you guys want to suggest a good (budget) cylinder head, intake, camshaft, & carb combo - I'm all ears! I don't mind a lopey idle but it's got to have enough vacuum at idle for power brakes. This might be a one day a week driver but never a daily driver... I hope...

Does anyone know if a dual plane intake will fit fit under the hood on a big block 67 camaro - RS/SS hood if that makes a difference. One of the Edelbrocks I found at Summit said that it would NOT fit under a Camaro or Chevelle hood.

thanks again

Jim

Originally Posted by 67_Pacer

Thanks everyone - if you guys want to suggest a good (budget) cylinder head, intake, camshaft, & carb combo - I'm all ears! I don't mind a lopey idle but it's got to have enough vacuum at idle for power brakes. This might be a one day a week driver but never a daily driver... I hope...

Does anyone know if a dual plane intake will fit fit under the hood on a big block 67 camaro - RS/SS hood if that makes a difference. One of the Edelbrocks I found at Summit said that it would NOT fit under a Camaro or Chevelle hood.

thanks again

Jim

the heads you have like i said will make 350 -400 hp EZ its intake .cr.cam and EX that build power there cams i have used but .get some head casting numbers .if you have the flat hood ?then not much .alow intake like the weiand X -celerator is a of the lowest

If hood clearance is a problem Chevy made some half decent low profile aluminum dual plane intakes for the Corvette and others. You mentioned square port heads, if they are similar to the Chevy high performance square port heads from the 60s-70s they may not be your best choice as they are made for higher RPM. Some of the oval port heads actually build better lower end torque and throttle response. Modern headers are much better than they used to be for sealing and exhaust leaks. They will make a big difference if combined with a 2" or better true dual exhaust. You will limit the benefit from the other mods you mention if you choke the exhaust.

Pat