Main seals on LT1 question
04-09-2018, 11:39 AM
#1
Racer
Thread Starter
Main seals on LT1 question
I'm debating adding the E-Force to my LT1 Z51 but am a little concerned with various feedback about the front/rear main seals being blown out due to crankcase pressure.
My plan is only for the Stage 1 7.5 boost and already have a E2 catch can (closed) system on the car so not sure if this assists with the issue or is the vented system a must when adding FI?
There is obviously some risk involved with adding boost to a car not designed for it but is the risk very high for the base kit?
TIA.
My plan is only for the Stage 1 7.5 boost and already have a E2 catch can (closed) system on the car so not sure if this assists with the issue or is the vented system a must when adding FI?
There is obviously some risk involved with adding boost to a car not designed for it but is the risk very high for the base kit?
TIA.
04-09-2018, 12:40 PM
#2
Team Owner
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ttt
Man put a catch can onto the car I did a MMS can to me the best one out here. You can always pull the can if you had a problem & had to have war work. But was reading from someone in here the 2017 & 2018 have a better PCV system on them than the 2014 & 2015 & 2016. 
Robert
Robert
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Clifftrail (04-09-2018)
04-09-2018, 04:13 PM
#3
Racer
Thread Starter
There are lots of folks that have gone FI on the LT1 here, is blowing out the front/rear main seal a rare event that is only occurring on high boost cars?
Or is it just the result of the new seals can't even take increased pressure from a base FI kit?
Or is it just the result of the new seals can't even take increased pressure from a base FI kit?
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Clifftrail (04-09-2018)
04-09-2018, 09:53 PM
#5
Melting Slicks
I have the stage 2 E force with 9 lbs of boost, I also have the Elite E2 catch can. I haven't had any issues.
I think the seals failing are on cars running more boost.
I think the seals failing are on cars running more boost.
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04-10-2018, 12:14 PM
#8
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The seal in the c7 is crap all the shop's are putting in the ls7 seal I believe to help with this problem. But for sure in a boosted car you need a catch can to help get pressure from the bottom.. Robert
04-10-2018, 02:47 PM
#9
Racer
Thread Starter
Are you saying the seals in the LT4 are the same? Do they have a different crankcase vent system to compensate?
04-10-2018, 03:14 PM
#10
Drifting
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2018 C7 of Year Finalist
830whp on a built 416 motor. Pushing about 12 lbs of boost and haven't had any issues with the seals yet. I do not have a catch can or any additional venting. Car goes WOT a decent amount and things have been holding strong. Mines a '14 Z51.
04-10-2018, 03:25 PM
#11
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you have a TSP 416 motor correct. Seals are the ls7 PUSH THAT PUPPY UP TO OVER 18 lets see what happens. 
04-11-2018, 07:18 PM
#13
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Smart man I only have a A/A TI unit I will not go any more than this in the car. If it blows I will be doing stock bore maybe 5,k over piston with all forged insides small cam & calling that a day in the car. Robert
04-11-2018, 08:14 PM
#14
Was front seal
Well fixed it and front seal —all messed up ,lowered timing back down boy does it run good with more timing I will miss that lol
And seems to run fine now also vent front two valve covers
And seems to run fine now also vent front two valve covers
Last edited by onebad1lE; 04-11-2018 at 08:16 PM.
04-18-2018, 03:02 PM
#15
If timing is affecting the blow by, which causes the seals to blow out, then that means the cars are detonating.
A non-detonating piston does not have as much ring flutter and will not let nearly as much pressure by.
In fact I have held the single crankcase vent pipe from an engine at load at 6k when there was no detonation and it was not more than minute breeze of air.
I would hazard a guess that with e85 there will be less blow by at the same timing as with pump gas. Unless someone got stupid with timing.
A non-detonating piston does not have as much ring flutter and will not let nearly as much pressure by.
In fact I have held the single crankcase vent pipe from an engine at load at 6k when there was no detonation and it was not more than minute breeze of air.
I would hazard a guess that with e85 there will be less blow by at the same timing as with pump gas. Unless someone got stupid with timing.
04-18-2018, 04:09 PM
#16
Le Mans Master
If timing is affecting the blow by, which causes the seals to blow out, then that means the cars are detonating.
A non-detonating piston does not have as much ring flutter and will not let nearly as much pressure by.
In fact I have held the single crankcase vent pipe from an engine at load at 6k when there was no detonation and it was not more than minute breeze of air.
I would hazard a guess that with e85 there will be less blow by at the same timing as with pump gas. Unless someone got stupid with timing.
A non-detonating piston does not have as much ring flutter and will not let nearly as much pressure by.
In fact I have held the single crankcase vent pipe from an engine at load at 6k when there was no detonation and it was not more than minute breeze of air.
I would hazard a guess that with e85 there will be less blow by at the same timing as with pump gas. Unless someone got stupid with timing.
Early on people were popping front seals left and right because tuners were approaching the LT platform like the LS platform...with gobs of timing. Too much timing will get you in trouble in a hurry with the LT platform. The same reason breather systems hit the market as well.
04-19-2018, 01:34 AM
#17
The Ls was taking more timing? The ls has lower static and dynamic compression. **** I think the stock lt1is pinging on 91 octane at 85 degrees ambient.
04-19-2018, 08:45 PM
#19
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To the guy above if it is what you are thinking, something is bad wrong with your car.
04-26-2018, 01:33 PM
#20
Exactly....
Early on people were popping front seals left and right because tuners were approaching the LT platform like the LS platform...with gobs of timing. Too much timing will get you in trouble in a hurry with the LT platform. The same reason breather systems hit the market as well.
Early on people were popping front seals left and right because tuners were approaching the LT platform like the LS platform...with gobs of timing. Too much timing will get you in trouble in a hurry with the LT platform. The same reason breather systems hit the market as well.
