I bought my car from Chicago about a year ago. It was extremely rigged when I bought it and I had to do a lot of work to make it reliable again. It came with a OBD1 B18B1 already swapped in it. Car is a 98 Civic EX.

I was told by the seller that the motor was previously boosted, but I have not confirmed this. My motor has definitely seen better days, as the compression checks out at about 140 on each cylinder.

I am planning on rebuilding it soon with all new seals and now piston rings. But I am not exactly sure if the rings are going bad from being boosted and driving on a blown headgasket multiple times, or if it has aftermarket low compression pistons in it. I want to be sure before I tear it apart and order the new parts for the rebuild.



This is a picture I took of the bottom end during a headgasket replacement. Can anyone confirm that these are stock pistons?

 

Better pics?

 

This is the only other picture I have. I wasn't aware of the compression problem until after I got the head back on.

 

my stock gsr pistons say p72 on them designating them oem gsr. The ls pistons might have a stamp on the top also

 

All oem Honda pistons have designators stamped on the dome. Usually starts with P followed by two numbers. Ls pistons are PR4.

 

I'm pretty sure I remember seeing PR4 on my pistons. From what I could tell when I bought the car it was ghetto boosted before. So I'm sure they just threw a turbo on a stock motor.

 

What type of rings should I get if I am just trying to make it reliable? OEM? And is there anything else I should replace, or any machining I should have done besides just putting new rings and seals on it?

 

I would just check it when you tear it apart for the rebuild! like said above it will say pr4.
Most new oem pistons will come with new rings or vise verse and are not that much more for new oem pistons.
If you say it was ghetto rigged with a turbo kit, chances are he didn't do it right! so i highly doubt the motor was fully built! don't have sleeves from the pic! and i doubt there's after market rods! so chances are he boosted a stock ls motor! probably cause it was dirt cheap for the ls swap.

You will want to check the piston wall clearances to see if it was bored out or not to determain the right size piston you will need! you never know if it was ever rebuilt in the past and they had bored the walls over. If it wasnt then check the walls and you might just need a light hone and have the top resurfaced if needed but not milled!! then you can just order the oem size pistons and rings and go from there. And do it right the first time dont cut corners use all new bearings have the crank inspected and refurbished or get a new one ect.