jusmillz

My car is a 08a6 ecs blower with headers and alky. I have a cracked piston in cylinder 7. My heart is broken right now . Well I guess I have to pull the motor right? What all must be replaced or upgraded in order to get back rolling safely? I have a budget of around 3500. I've been reading posts and some have just swapped the 1 piston, some have completely forged everything, and some just got forged piston. I know there are no cheap fixes but I won't the most economical and safe did for this. Any ideas or sugesstions ?

Tech

Depends if the piston damaged the sleeve enough to warrant replacement. The cost to fix it will also depend on how much of the work you do.

jusmillz

walls look clean and undamaged, also no head damage either.

neverstop

if you're on a budget and looking to make 700whp or less I'd just grab a junkyard ls2 or ls3 and swap it for cheap. hard to say how messed up it is without pulling it out and looking at the sleeves. if the sleeves are ok you could probably get some cheap pistons/rods and get it put back together for maybe your budget?

I would certainly not try just putting a new piston in there with the motor in the car. Odds of that working out well imo are about zero.

subfloor@centurytrans

Uh, no....


Last month I ended up having this happen to my #6 piston at the track:






After determining it was a clean break (no damage to the cylinder wall or any of the valves) I swapped in a replacement piston (using new rings and rod bearings) with the motor still in the car. I'll let this video from last week speak for itself as to how the overall operation went:

neverstop

wow, that's nuts. I've never seen a piston break/crack without at least scraping the cylinder wall at least a little but learn something new each day. can't believe it passed a chunk that big out the exhaust valve.

on the various stuff I've blown up over the years, some much less horrible looking than that piston, I've always had cylinder damage but apparently i've just had terrible luck or something

stevieturbo

If 1 is damaged, good chance more of them are too. Replacing only one is usually a fools game and will come back to bite you alter unless you're incredibly lucky.

If you're really on a budget you could just fit some new pistons....but rods are cheap so may as well chuck a set of rods in too.
If the bores dont need any work other than a light hone, you'll get away with good savings.

c5mtl

Oh boy!!!! 'May as well" is very dangerous phrase

stevieturbo

So is "chuck a set in" but I'm sure people would understand not to take it literally.




I hope lol Clearly parts need selected and installed correctly by a competent person.

KSA Aaron

I lost #7 on my TT set-up. I put a good number of miles on it after the damaged piston, but it always had the CEL and very low compression in #7. Pulled it apart and found that #7 piston oil control and lower compression rings were damaged as well as the ring land areas, but the cylinder wall was in good shape.


This past Christmas, my son and I tore into the engine and replaced those items that were damaged and buttoned everything back up. All GM parts at a cost of ~$165 all in.


She runs great!

DOUG @ ECS

Nice way to turn lemons into lemonade.

I have swapped pistons several times over the years with a 100% success rate.

NJ_phil

That was anti climactic. I was waiting for the explosion that never came.