i dont think he wants to hear that...lol 
Dyno results
Thread Starter
TECH Apprentice
Joined: Nov 2005
Posts: 304
Likes: 0
From: Newmarket, Ontario
Dyno results Just got back from the dyno..
The good news - made 553 hp @ 5500rpm @ 10.5 psi.
The bad news - We heard a noise.
The shop thinks it is the turbine compressor wheel hitting the housing, it makes like a tick-tick-tick noise then goes away. We did a couple pulls, then heard the noise, then it went away, so we did a couple more pulls, and it came back, so we stopped. Since I drove home I can not hear it. The turbo is a brand new precision Garrett GT42 (with only about 10 - 15 dyno pulls on it).
1. What could have caused this if it is in fact the case?
2. Other than taking my compressor housing off, how can I check if that is the problem?
3. What else should I check for?
Did not get a chance to do a pull in 5th (as we were going to do that after everything was dialed in), but I phoned the dynojet guys and they said that it should work fine.
Did not get a chance to modify meth amount, used 400cc/min, seemed to be the right amount.
The good news - made 553 hp @ 5500rpm @ 10.5 psi.
The bad news - We heard a noise.
The shop thinks it is the turbine compressor wheel hitting the housing, it makes like a tick-tick-tick noise then goes away. We did a couple pulls, then heard the noise, then it went away, so we did a couple more pulls, and it came back, so we stopped. Since I drove home I can not hear it. The turbo is a brand new precision Garrett GT42 (with only about 10 - 15 dyno pulls on it).
1. What could have caused this if it is in fact the case?
2. Other than taking my compressor housing off, how can I check if that is the problem?
3. What else should I check for?
Did not get a chance to do a pull in 5th (as we were going to do that after everything was dialed in), but I phoned the dynojet guys and they said that it should work fine.
Did not get a chance to modify meth amount, used 400cc/min, seemed to be the right amount.
Be the easiest and best way just to pull the compressor housing off, which is pretty easy to do on the GT42. That way you can check the compressor blades and housing itself real close.
Probably wasn't hitting. My Tial BOV makes a pretty low key shh-shh-shh after getting out of boost.
J
Probably wasn't hitting. My Tial BOV makes a pretty low key shh-shh-shh after getting out of boost.
J
Thread Starter
TECH Apprentice
Joined: Nov 2005
Posts: 304
Likes: 0
From: Newmarket, Ontario
I'll check for sure, the other thing is that it made the noise even at 10inch vac., but when you get of the throttle, it goes away???
It definately was not a screeetch sound.
Any ideas what could cause it if it is the turbo?
Any ideas what else it could be?
It definately was not a screeetch sound.
Any ideas what could cause it if it is the turbo?
Any ideas what else it could be?
Trending Topics
The turbine side and compressor side are seperate parts. If one side is hitting then more than likely, the other side is hitting. It would NOT be a random tick-tick-tick...it would last all the time and you would be able to hear it.
If the compressor side were touching the housing, you should be able to take off your air inlet and see if the wheel is touching the sides. It is probably something else as frcefed described and others describe.
If the compressor side were touching the housing, you should be able to take off your air inlet and see if the wheel is touching the sides. It is probably something else as frcefed described and others describe.
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
..... Ive heard that noise before.......... 
Sounds like the exhaust wheel or the impeller blade is rubbing the housing......take it off now and have the clearing and shaft play checked before you mess up more things........
Sounds like the exhaust wheel or the impeller blade is rubbing the housing......take it off now and have the clearing and shaft play checked before you mess up more things........
Originally Posted by bigturboz28
Just got back from the dyno..
The good news - made 553 hp @ 5500rpm @ 10.5 psi.
The bad news - We heard a noise.
The shop thinks it is the turbine compressor wheel hitting the housing, it makes like a tick-tick-tick noise then goes away. We did a couple pulls, then heard the noise, then it went away, so we did a couple more pulls, and it came back, so we stopped. Since I drove home I can not hear it. The turbo is a brand new precision Garrett GT42 (with only about 10 - 15 dyno pulls on it).
1. What could have caused this if it is in fact the case?
2. Other than taking my compressor housing off, how can I check if that is the problem?
3. What else should I check for?
Did not get a chance to do a pull in 5th (as we were going to do that after everything was dialed in), but I phoned the dynojet guys and they said that it should work fine.
Did not get a chance to modify meth amount, used 400cc/min, seemed to be the right amount.
The good news - made 553 hp @ 5500rpm @ 10.5 psi.
The bad news - We heard a noise.
The shop thinks it is the turbine compressor wheel hitting the housing, it makes like a tick-tick-tick noise then goes away. We did a couple pulls, then heard the noise, then it went away, so we did a couple more pulls, and it came back, so we stopped. Since I drove home I can not hear it. The turbo is a brand new precision Garrett GT42 (with only about 10 - 15 dyno pulls on it).
1. What could have caused this if it is in fact the case?
2. Other than taking my compressor housing off, how can I check if that is the problem?
3. What else should I check for?
Did not get a chance to do a pull in 5th (as we were going to do that after everything was dialed in), but I phoned the dynojet guys and they said that it should work fine.
Did not get a chance to modify meth amount, used 400cc/min, seemed to be the right amount.
....... It can be random ............trust me been there done that..........but it will speed up slighly with RPM.........It does become more consistant as time goes though...........not proud of it just had my share of misfortune..
Originally Posted by NOSjohn
The turbine side and compressor side are seperate parts. If one side is hitting then more than likely, the other side is hitting. It would NOT be a random tick-tick-tick...it would last all the time and you would be able to hear it.
If the compressor side were touching the housing, you should be able to take off your air inlet and see if the wheel is touching the sides. It is probably something else as frcefed described and others describe.
If the compressor side were touching the housing, you should be able to take off your air inlet and see if the wheel is touching the sides. It is probably something else as frcefed described and others describe.
As stated inspect both the exhaust side and the compressor side and look for any chips, nicks or scratches in the blades. Check the shaft for side to side play and that the nuts are not back out of otherwise causing an issue. It is hard to say what it is without hearing it first hand and I realize that this may seem like allot of work but it is MUCH better to take the time and do it rather than have the turbo come apart on you and end up in the motor. Trust me that is NOT funny at all!!! Mine was a defect but Harry Hruska made it right without issue.
Jim C.
Jim C.
Thread Starter
TECH Apprentice
Joined: Nov 2005
Posts: 304
Likes: 0
From: Newmarket, Ontario
Thanks for all the input, I will take er apart this weekend and keep you upto date.
I'm running 60lb injectors, and twin walbro 255hp intank pumps, I don't know the exact number but there was lots of injector left. Also don't believe the myth that it is to hard to tune with 60lb, it is bullsh*t. Do not waste your money going to 38lb then 42lb then 60lb, just go 60lb. If your goals are higher then the 60lb'ers will get you, I can not speak to that, maybe someone else can chime in about tuning low hp (~500rwhp) with 72lb or 96lb injectors.
-EDIT-
One more thing to add, as time went on in the dyno runs the engine bay got hot (no sh*t), but the lines I used to connect the BOV were that clear vinyl stuff. I noticed that they were collapsed due to vacumm and them getting softer due to heat, any ideas if this could have contributed?
I'm running 60lb injectors, and twin walbro 255hp intank pumps, I don't know the exact number but there was lots of injector left. Also don't believe the myth that it is to hard to tune with 60lb, it is bullsh*t. Do not waste your money going to 38lb then 42lb then 60lb, just go 60lb. If your goals are higher then the 60lb'ers will get you, I can not speak to that, maybe someone else can chime in about tuning low hp (~500rwhp) with 72lb or 96lb injectors.
-EDIT-
One more thing to add, as time went on in the dyno runs the engine bay got hot (no sh*t), but the lines I used to connect the BOV were that clear vinyl stuff. I noticed that they were collapsed due to vacumm and them getting softer due to heat, any ideas if this could have contributed?
Last edited by bigturboz28; Mar 25, 2006 at 04:38 PM.
Thread Starter
TECH Apprentice
Joined: Nov 2005
Posts: 304
Likes: 0
From: Newmarket, Ontario
something??? ran through the exhaust side turbine, the base of the blades (where there is a big gap to the housing, or at least there is now??) have little chips out of them. The intake side was untouched. The only scary part is that if the blades that are far away from the housing have been damaged, what was causing the noise? Could whatever went through there "kicked" the shaft and damaged a bushing? or is the turbine out of balance now and causing a problem? Any ideas on what a new exhaust turbine costs?
Any comments?
Any comments?
Thread Starter
TECH Apprentice
Joined: Nov 2005
Posts: 304
Likes: 0
From: Newmarket, Ontario
I don't think piston, I'm thinking more along the lines of a piece of weld, I did a last minute "tack" to ensure it was not leaking, but I think I might have melted a chunk in the exhaust pipe that broke off (and I learn it AGAIN - do it right the first time). The other reason I don't think piston is that the car still runs very strong.
Would the car run strong if a chunk of piston was missing? wait, I know, I know - Maybe, it depends, right?
Would the car run strong if a chunk of piston was missing? wait, I know, I know - Maybe, it depends, right?
Originally Posted by bigturboz28
I don't think piston, I'm thinking more along the lines of a piece of weld, I did a last minute "tack" to ensure it was not leaking, but I think I might have melted a chunk in the exhaust pipe that broke off (and I learn it AGAIN - do it right the first time). The other reason I don't think piston is that the car still runs very strong.
Would the car run strong if a chunk of piston was missing? wait, I know, I know - Maybe, it depends, right?
Would the car run strong if a chunk of piston was missing? wait, I know, I know - Maybe, it depends, right?
Im not trying to scare u or anything.... Its just a thought. I hope its a small problem and u get it fixed.