, posted about the same time as you did Kp. Looks like we're on the same wave length here. 
Found some boost leaks.
Found some boost leaks. For one the procharger race bypass will not hold 2 lbs of air. I pulled all IC pipes off from the outlet of the blower to the inlet of the TB and put a Air test on it. I changed out 1 nitrile 90 and put a silicon on it its place with
T-bolt clamps. It does not leak anymore. I tightend the outlet side of the IC up and it dont leak anymore. I had to reweld the BOV saddle where they had a hole in it and leaking air. So another one leak fixed. Only 2 leaks left the BOV itself and the IAT sensor. It is leakeing through the sensor itself. I put some silicone where the plug gos into the sensor. I dont know if it helped or not it was leaking bad it wouldnt hold air for nothing. I have a block off plate on the mounting flange for the bypass. Now its acting funny the blower sounds funny now when i rev it up. Expecially when i let off the gas. Do I need the vavle on there or not? Any ways it was on the trailer and i put it up on the transbrake and i still only saw 5-6 lbs of boost. It might be more when i get out and drive it. So thats what i have for the current time. I sure hope its not the blower. Any ideas on how to fix the IAT sensor? And what to do on the BOV?
T-bolt clamps. It does not leak anymore. I tightend the outlet side of the IC up and it dont leak anymore. I had to reweld the BOV saddle where they had a hole in it and leaking air. So another one leak fixed. Only 2 leaks left the BOV itself and the IAT sensor. It is leakeing through the sensor itself. I put some silicone where the plug gos into the sensor. I dont know if it helped or not it was leaking bad it wouldnt hold air for nothing. I have a block off plate on the mounting flange for the bypass. Now its acting funny the blower sounds funny now when i rev it up. Expecially when i let off the gas. Do I need the vavle on there or not? Any ways it was on the trailer and i put it up on the transbrake and i still only saw 5-6 lbs of boost. It might be more when i get out and drive it. So thats what i have for the current time. I sure hope its not the blower. Any ideas on how to fix the IAT sensor? And what to do on the BOV?
TECH Addict
Joined: Nov 2001
Posts: 2,659
Likes: 1
From: Bellevue, Wa
you NEED a bypass of some sort
otherwise the extra air has nowhere to go and your going to destroy your blower as the air fights to spin the compressor the opposite direction.
dont run it without a bypass or blowoff!
otherwise the extra air has nowhere to go and your going to destroy your blower as the air fights to spin the compressor the opposite direction.
dont run it without a bypass or blowoff!
This was just for testing to see where the boost is going. The valve would not hold a pound of air. Rob Raymer said it wasnt slipping when he looked at the car tuesday nite and i see no signs of it. What could there be wrong with the bypass, like a weak spring, not adjusted correctly, or just a bad valve? And the IAT sensor and ideas how to fix that?
If all the vanes are on the impeller and the housing isnt scored there is nothing wrong with the blower. Either belt slip or the pulley is slipping on the shaft can be wrong there if it looks undamamged..
I'm not sure how the ATI race bypass is but some BOVs have two fittings for the vacuum lines and if you hook it up backwards there is is no boost, the boost will open the valve instead of keeping it closed. Also a lot of bypass valves wont hold any pressure, they rely on the boost coming from the hose to hold it shut, never seen the big ATI so I dont know how that one works..
I was recently messing with a turbo that the BOV was hooked up wrong and even with the BOV wide open at full throttle it still made 5psi of boost with a 1.5" diameter hole in the intercooler. Made 13psi with the BOV hooked up the right way.
And yes like blackbird said you NEED a bypass.
The IAT sensor leaking wont cost you much, I wouldnt worry about that.
I'm not sure how the ATI race bypass is but some BOVs have two fittings for the vacuum lines and if you hook it up backwards there is is no boost, the boost will open the valve instead of keeping it closed. Also a lot of bypass valves wont hold any pressure, they rely on the boost coming from the hose to hold it shut, never seen the big ATI so I dont know how that one works..
I was recently messing with a turbo that the BOV was hooked up wrong and even with the BOV wide open at full throttle it still made 5psi of boost with a 1.5" diameter hole in the intercooler. Made 13psi with the BOV hooked up the right way.
And yes like blackbird said you NEED a bypass.
The IAT sensor leaking wont cost you much, I wouldnt worry about that.
TECH Enthusiast
Joined: Aug 2003
Posts: 596
Likes: 0
From: Downers Grove,IL
Did you apply the same pressure to the bypass valve vacuum/boost fitting when you pressure tested it?
The bypass needs a pressure source to seal.The spring does not do the sealing, the diaphragm does.If it won't seal with a pressure source then something is wrong with it.
Also did you look at the blower inlet just to make sure all the impeller vanes are still intact?
Get a screw in sealed IAT sensor to replace the plastic LS1 unit. Mototron sells them for 11.70$- http://www.mototron.com/products.htm
Steve
The bypass needs a pressure source to seal.The spring does not do the sealing, the diaphragm does.If it won't seal with a pressure source then something is wrong with it.
Also did you look at the blower inlet just to make sure all the impeller vanes are still intact?
Get a screw in sealed IAT sensor to replace the plastic LS1 unit. Mototron sells them for 11.70$- http://www.mototron.com/products.htm
Steve
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Originally Posted by S_J_H
Get a screw in sealed IAT sensor to replace the plastic LS1 unit. Mototron sells them for 11.70$- http://www.mototron.com/products.htm
Steve
Steve
-Geoff
Originally Posted by Caveman
This Mototron company has a 60lb injector on their site, is that the same inj. that some of you guys are using??
Kyle
No Steve i did not apply any pressure to the vacuum fitting the would be why it is leaking then. Maybe I need to reroute the vacuum signal to the intake or something instead of where its at now. Yea ill have to Remove the Stock IAT they epoxyed in and put a screw in sensor in its place, my camaro has a screw in sensor in it, that seems to work good. Also on the allen screw on top of the BOV i have it cranked down will this help or hurt anything? So u are saying the blower pully can be slipping on the shaft? Guess i need to check that out also and put the BOV back on. Any other ideas or checks i can do to get this thing running right? Thanks Justin
I doubt the pulley is slipping on the shaft, I was just saying thats the only thing that can be wrong with the blower if the impeller looks OK. Unless someone forgot to put the key in it wont slip, you would have noticed the metal shavings by now if te key wasnt in there.