Bottom End Help

[evad]

Hey everyone, I am having to do some bottom end work. My sr20det needs new pistons, and possibly sleeves. Looking at CP pistons and darton sleeves at 86.5 or 87mm bore. I am gonna do an overhaul kit and water pump as well.

My question is...should I really spend the money on rods or stick with the stock ones? I am just keeping the car on the street for a fun street car that will put down some decent power after I upgrade the turbo later this year.

Suggestions and help would be great. Thanks.

[compactfean]

Your setup is very confusing. Sleeves are only for big big power. Pretty much the stock bottom end can handle any pump gas 91 octane tune (around 350 -400hp). If you run 93 octane 400 to 450 hp. I would rec pistons anywhere above 350 just from a reliability standpoint. But the stock rods have proven themselves in 550 hp race gas setups. I have sleeves and spent 1,000 on them and install and boring but that's only because my final resting with this motor will be at 35 psi+ on race gas. If you are planning on just a street car and not an all out drag car I would get good bearings, get the stock rods shot peened, forged pistons only to the next size up and bore the stock block. Spend the exta $1000 on all your other stuff like inj,maf,ecu for when you upgrade your turbo and need it tuned.

[evad]

The only reason I am thinking of sleeving the motor is because a piece of the no. 1 piston chipped off and scratched up the no. 1 cylinder pretty bad. The block is at a machine shop now to see if the sleeve needs replacing or if it can be bored.

[compactfean]

I gotcha. Back in the day I would have said just get another motor, but with how old sr20 engines are getting there isnt many that don't need work. .5 mm is .020 inch over witch is still ok. I think 87mm pistons is max but usually .020 will get rid of any nicks. If you have to sleeve it so be it, itll be that much stronger but if you dont have to than that's more money for the rest.