Chevy Iroc Z

I got sb 350 zz4 shortblock afr 195 heads and 100shot nitrous

Car runs 11.80 so far 116mph

I want to spray more nitrous is there a forged piston that i can put in this motor that is a direct replacement? Can i take apart and just replace piston and rings? Its got low mileage maybe 1500 miles on it and 10 1/4 mile passes.

AlkyIROC

Yes and no.

Chances are you have pressed in wrist pins. This means doing a piston swap isn't a typical job the average person can do. A special jig is used to hold the piston to keep it from being damaged while the wrist pin is being pressed out.

It's a little easier to install but you need a torch to heat up the small end of the con rod so that the wrist pin can be dropped in. Once the con rod cools down, it holds the wrist pin in place.

Floating wrist pins are much easier. They are held in with lock rings in the piston and no special tools are required.

However, it's not a simple matter of removing old pistons and installing new ones. The bore needs to match the clearance required for the new pistons. The new pistons/wrist pins will also be a different weight than the old ones so a complete rebalance needs to be done.

Changing pistons requires a complete tear down of the engine. Might as well get it put back together properly if you want it to survive.

anesthes

iTrader: (12)

Yes, a TRW 2256F is a factory weight replacement piston (610 grams).

If the motor only has 1500 miles on it, you might not even need to re-hone it.

The 2256 uses a low expansion alloy, so a cylinder sized for a cast piston will work fine.

You will bring your rods + pistons to a machine shop and have them swap them, then re-install them into the engine with new rings.

-- Joe

Chevy Iroc Z

cool. will this piston take 250 shot of nitrous and last a little while

anesthes

iTrader: (12)

They will last forever if you don't detonate.

I've run them in 600hp applications.

-- Joe