N/A Pistons and Rods

[Lienhop Photo]

Well I am shopping for 5 speed swap parts and I was looking on Rockauto.com and saw some pistons for sale.

I am building the N/A motor for auto cross. I am replacing the headgasket right now and the block will be apart soon. So, my question is should I get new pistons and rods. Maybe the $25 ones on Rock auto. I just want it more reliable because the motor has about 250k on it right now.

Thanks

 

[Moy]

That $25 you're seeing is for the rings, the pistons are $130

 

[Lienhop Photo]

i ment to add that. Do you think its worth replacing even if there not in the best conditction

 

[Moy]

honestly at 250K if you plan on racing it, I'd just rebuild the entire engine.

Do you plan on staying N/A?

 

[Lienhop Photo]

yea I dont see the need to go above NA. autocross courses in wilmington r pretty small. I dont need 250hp or more to be sliding around everywhere

 

[Moy]

Hahaha. Driftmotion sells a set of NPR pistons and rings (I'd go .020" overbore) for $120 plus shipping. I'd get the headgasket surface decked and have the cylinders overbored .020" to eliminate the taper at the bottom of the cylinder.

Your rods should be fine. You could buy new ones off of Rock Auto, or find someone on here selling a used set (lower mileage). N/A and Turbo are the same.

I'd also deck the head's headgasket surface. Replace valve stems, springs, retainers, keepers, seats, and valves.

May as well have new parts in it, right?

 

[89nasupra]

i agree with Moy. with that many miles it would be a good idea to do a complete rebuild. you will be running it hard even if it is for only a short time. might want to lookin to some cams also to give you a little more low end power.

 

[Another MkIII]

If I was you, with 250K on it, I wouldn't consider anything less than a full rebuild. If you are staying N/A, might as well go to a higher compression if you can find them. But most the stuff I see is for Turbo motors, not a lot of people stay N/A.
-AM3

 

[gofastgeorge]

Wiseco makes a 10.5:1cr piston, and I think someone like CP or JE makes an 11:1 or so.

You are not going to get to 250hp with out them,
and big cams,
and big valves,
and a larger throttle,
and headers,
and dumping that damn swinging barn door air flow meter for something like a MAP-ECU.

In other words, spending a lot of money to go a little faster than slow.

Do a mild turbo conversion, and have room to spare.
No reason to replace the rods, they don't go bad unless you ran the thing until the bearings fried.
Stock rods are good to the 500hp range.