Blew tops of pistons

**matt5112** · 04-30-2013

Pictures of holes? Unless you mean the ring landing of the pistons are "chipped" around the 1 o'clock position.

It has been said that the NA engines don't handle detonation as well as the SC engines. And the SIII doesn't handle it as well as the SII.

Also been said that KR over time will weaken piston and they can fail without seeing KR.

If and when you do this again, aim for 1* of KR max even in third gear. Even then, play it safe and aim for zero.

And don't tune around KR, adjust the pulley size or fix the mechanical issue causing it.

Should last longer, but there's always that chance.

**01GrandPrixTURBOGT** · 04-30-2013

Yea where the alt bolts in. And I don't have pics yet its still at hos shop. But he said tops of pistons had holes.

**dsmuts** · 04-30-2013

The valve cover has a hole because someone put the wrong bolt in there.

**01GrandPrixTURBOGT** · 04-30-2013

That wouldn't cause it to be lean though.

**Scottydoggs** · 04-30-2013

Originally Posted by 01GrandPrixTURBOGT

That wouldn't cause it to be lean though.

it lets tons of un metered air into the engine.

**GTPpower** · 04-30-2013

Originally Posted by Scottydoggs

it lets tons of un metered air into the engine.

**01GrandPrixTURBOGT** · 04-30-2013

well i dont know what else it could be fuel pressure was fine when i tested after the swap

**dsmuts** · 05-01-2013

Did you test fuel pressure while driving at wot? That's when you'll see the drop off

**jlgp2007nc** · 05-01-2013

Originally Posted by dsmuts

Did you test fuel pressure while driving at wot? That's when you'll see the drop off

My next gauge

**01GrandPrixTURBOGT** · 05-01-2013

No I didn't the gauge I had from oreilys wouldn't reach.

**01GrandPrixTURBOGT** · 05-01-2013

What gauge do you guys recommend for fuel pressure and afr?

**Sandman** · 05-01-2013

AFR I'd do with an AEM.

**01GrandPrixTURBOGT** · 05-01-2013

What do you guys think of the fail safe wideband?

**jlgp2007nc** · 05-01-2013

I just have the UEGO wideband. Don't know what the difference is but mine has outputs you can tap into HP Tuners pro and I log my afr in my scans but I read the gauge to see whats going on while im driving. All I really need. Can peek on the go and read logs when I sit down to change numbers.

**01GrandPrixTURBOGT** · 05-01-2013

Ok i may try that one out. So what numbers or ranges am I looking for?

**jlgp2007nc** · 05-01-2013

Idle and cruise will always jump around as the computer switches rich/lean but once you enter PE it should lock in to some degree. 14.3-15.2 idle abd cruise. For another high compression top swap build try 11.0 in boost.

**01GrandPrixTURBOGT** · 05-01-2013

Ok so the 14.3 is just n/a?

**jlgp2007nc** · 05-01-2013

No that's cruise and idle afr. Should always be as close to 14.7 as possible but you'll see a little variation. Normal at idle and cruise.

**01GrandPrixTURBOGT** · 05-01-2013

O yea duh 14.7 is normal haha. So when I get my car back what should I look for first? Fuel pressure and afr while cruising I know can one gauge do this? Also anything else that would cause chipped pistons besides kr.