i have an eg hatch with a 99 gsr swap and im boosting 10 psi. The other day im pretty sure i blew a piston so i dont want to drive it until i fix it. I was thinking of taking out the block and boring it and getting new pistons and rods or just getting a gsr block off craigslist. I dont have unlimited funds so im wondering what would each cost and what is better. any input or help would be great!!

 

I all depends on a lot of factors. Whats the condition of the block you have? How do you know you blew a piston? Like a hole in the piston, rod noise, piston blow by, we need more info first step is to properly diagnose the problem. Compression test will help it needs to be 180psi or something with 10psi another stock lower end will probably blow again depending on the tune. You need to strengthen the lower end.

 

I agree with totalkhaos24, need to look further into your engine and see what is really goin on. If you did kill a piston then you know what the next step is ala forged pistons and rods would do the trick. But there are guys running strong on cast pistons too. It's all in the tune, but forged pieces gives you a little more strength on the bottom end.

 

I don't know the condition of the block I have only done head work, but a blown piston is just a guess, I have seen and heard cars with blown pistons and mine seems similar so that's why I thought it mite be that. I havent done any diagnosing and I haven't ripped apart my engine bc I wanna no if I have to or not. So you think a compression test will tell me? Or what else should I do as far as figuring out the problem?

 

Do a compression and leak down test

 

What will i be looking for in the tests if i have a blown piston?

 

If you have a blown piston like a hole in it. It will have no compresson 0 psi. Remember to disable the ignition system so the vehicle does not start. What does the motor sound like? Does it run? Can you pull a spark plug wire on at a time for each cylinder and does the engine change like runs rougher or stays the same then you can eliminate what cylinder you are after.