[714camaro]

Hey guys, so i discovered that I blew my front main seal on my 16 Camaro ss. It’s a boosted car: LT4 blower, LT4 low side fuel pump, 2.3 upper, sbe. I know a lot of guys have reported their seals had flipped but pistons were fine. On the other hand i know there are also a number of others that had piston failure as well.

I’m pretty worried about my pistons. I have 93,000 miles on the car and about 20,000 boosted miles @ 11lbs. I don’t want to just put a new seal on the car if my internals are f’ed. Are there any tests that can be done to check the pistons? I don’t quite have deep enough pockets for forged internals yet, so I’m faced with some difficult decisions.

I’m looking for a reputable shop in Orange County, ca area who can maybe help out in diagnosing the issue.

Thanks in advance.

[Tim M]

Compression test may give indications...leak down test is best. Lot of miles on it - you did well!

[LT1ornothing]

Originally Posted by 714camaro

Hey guys, so i discovered that I blew my front main seal on my 16 Camaro ss. It’s a boosted car: LT4 blower, LT4 low side fuel pump, 2.3 upper, sbe. I know a lot of guys have reported their seals had flipped but pistons were fine. On the other hand i know there are also a number of others that had piston failure as well.

I’m pretty worried about my pistons. I have 93,000 miles on the car and about 20,000 boosted miles @ 11lbs. I don’t want to just put a new seal on the car if my internals are f’ed. Are there any tests that can be done to check the pistons? I don’t quite have deep enough pockets for forged internals yet, so I’m faced with some difficult decisions.

I’m looking for a reputable shop in Orange County, ca area who can maybe help out in diagnosing the issue.

Thanks in advance.

What type of fuel were you using for 11 lbs in California? Good 'ol Cali Premium pump 91 octane?

[714camaro]

Originally Posted by 1LEornothing

What type of fuel were you using for 11 lbs in California? Good 'ol Cali Premium pump 91 octane?

Correct, 91 is all that is available around here. I used to be on e-85 when i was na but have been running 91 since going boosted.

[LT1ornothing]

Originally Posted by 714camaro

Correct, 91 is all that is available around here. I used to be on e-85 when i was na but have been running 91 since going boosted.

I am amazed it lasted as long as it did. You probably have piston damage. Should have been running 91 mixed with e85 on your set up with a good catch can. 93 octane is barely enough for a stock LT1, running pump 91 on a stock LT1 with a supercharger is a guaranteed engine failure.

[laynlo15]

Been there as many others have. Since you pushed the front seal out its usually number 1 cylinder which is on the drivers side front. That's what happened to me, I replaced the seal not knowing at the time it was the I had a broken ring land. I continues to race the car for a couple more months until I finally broke number 8 cylinder and pushed the rear seal out. Oppps, then it was time for a new forged short block. Block and crank were ok so we just bored the block 10 over and went with Manely Forged Pistons and Rods, polished the crank , new BTR cam, freshened up the heads, all APR Studs and bols. I think I spent about 8 to 9K including all parts with some labor. We were running about 16 lbs of boost with the 2300 Maggie on MS 109 VP Race Fuel and spraying some meth/water to help out with fueliing. So not cheap by any means. Good luck

[Joshinator99]

Originally Posted by 1LEornothing

I am amazed it lasted as long as it did. You probably have piston damage. Should have been running 91 mixed with e85 on your set up with a good catch can. 93 octane is barely enough for a stock LT1, running pump 91 on a stock LT1 with a supercharger is a guaranteed engine failure.

Agreed. On 91 octane you should have been running 7 pounds of boost, not 11. Really a miracle it lasted as long as it did.

Agree with Tim M about the compression test.

[laynlo15]

Originally Posted by Joshinator99

Agreed. On 91 octane you should have been running 7 pounds of boost, not 11. Really a miracle it lasted as long as it did.

Agree with Tim M about the compression test.

Josh, I meant to say something about that but I totally agree with that. I'd say 9 lbs max.

[95 imp]

I vote leak down test. Maybe you can see it with a bore scope.

91 and boost do not play well together. On my N/A, I use 1 gal of xylene per 10 gal of 91 which brings it up to 93. Or, lately, a half gallon xylene and 3 oz MTBE (max MTBE recommended for catted cars)

The extra octane booster is still cheaper than pistons.

[714camaro]

Thanks guys. 1LEornothing, I cant blend E with 91 on the lt1 fuel system because it requires more volume and im near maxed on my fuel system. This is why I didn't blend in the first place. I even asked my tuner to dial the boost back with a bigger pulley because I wanted longevity, not max power. Looks like Ill be replacing the seal and adding a mms wild catch can. Ill have a leak down test done while Im at it.

[714camaro]

Originally Posted by laynlo15

Been there as many others have. Since you pushed the front seal out its usually number 1 cylinder which is on the drivers side front. That's what happened to me, I replaced the seal not knowing at the time it was the I had a broken ring land. I continues to race the car for a couple more months until I finally broke number 8 cylinder and pushed the rear seal out. Oppps, then it was time for a new forged short block. Block and crank were ok so we just bored the block 10 over and went with Manely Forged Pistons and Rods, polished the crank , new BTR cam, freshened up the heads, all APR Studs and bols. I think I spent about 8 to 9K including all parts with some labor. We were running about 16 lbs of boost with the 2300 Maggie on MS 109 VP Race Fuel and spraying some meth/water to help out with fueliing. So not cheap by any means. Good luck

Where did you end up purchasing the forged shortblock? 8-9k sounds very reasonable. I was quoted 6k just for labor on drop ins.

[LT1ornothing]

Originally Posted by 714camaro

Thanks guys. 1LEornothing, I cant blend E with 91 on the lt1 fuel system because it requires 30% more volume. This is why I didn't blend in the first place. I even asked my tuner to dial the boost back because I wanted longevity, not max power. Looks like Ill be replacing the seal and adding a mms wild catch can. Ill have a leak down test done while Im at it.

A full LT4 fuel system upgrade is the minimum any reputable performance shop will tune a stock LT1 with boost. Most suggest this with a voltage pump booster and flex fuel sensor so that the system can be tuned on a safe e blend of around E50, preferably without catalytics. Truly amazing it lasted as long as it did. Hope you can get by with a front seal replacement, but chances are there is piston damage too, good luck.

[714camaro]

Thanks again to everyone who chimed in. I will keep this thread updated as I go

[714camaro]

On a side note, does anyone know why i would be missing a line on my boost bypass valve? I never asked my tuner why it was set up that way.