UPDATED!!*DYNO NUMBERS* Comparison of Comp Turbo Billet 88mm CT6X-88 & GT91 Garrett!!
#61
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Well here's the update: the highest temp today was 108 degrees, so not too good to start. The car made good power in the lower settings, and it seemed like the boost came in quicker and didn't drop off as bad in the upper rpm's. When we tried the high boost setting (17psi) it would only make about 14lbs. It was making about 850rwhp and increasing the boost controller even wouldn't up the boost. The car was getting really hot, so we cooled it down and tried again with no luck. I ended up taking it home without figuring it out. I checked for boost leaks but couldn't find any....
Any ideas guys?
Any ideas guys?
#64
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i dont know where you are getting the an inducer or exducer measurment on that turbine because they are the same
in the pics that is a 100 trim straight cut wheel
what is the major diameter of it?
how many lb springs do you have in the wastegates? i am willing to bet u are seeing an increase of drive pressure which is overcoming the gates sooner than the last turbo
if this is the case, it is not breathing aswell as the last turbo
in the pics that is a 100 trim straight cut wheel
what is the major diameter of it?
how many lb springs do you have in the wastegates? i am willing to bet u are seeing an increase of drive pressure which is overcoming the gates sooner than the last turbo
if this is the case, it is not breathing aswell as the last turbo
#65
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Guys, Keep in mind the only thing that changed was the turbo. That was a typo on the first page, It is a 94mm turbine wheel (100trim) much bigger than the old one. the only thing I can think is that there is something wrong with the turbo, or that I have some new boost leak somewhere
#67
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check this thread out http://www.yellowbullet.com/forum/sh...d.php?t=477708
He ended up sending the turbos back & now it spools up fine.
He ended up sending the turbos back & now it spools up fine.
#71
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These are the things I was going to test this weekend:
Remove compressor cover & check for blade damage
Check all couplers for leaks (pressure test)
Measure backpressure
Do some testing with the eboost
#73
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I completely agree, however these turbos were'nt put together by kids. The wheel is cast Inconel, and I can guarantee Comp is not manufacturing that part, they are probably buying it from honeywell, borg warner, etc...
do you have some sort of experience with these turbos? Im wondering why you so adamantly think its the turbine wheel. Please share if you do.
do you have some sort of experience with these turbos? Im wondering why you so adamantly think its the turbine wheel. Please share if you do.
#74
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When I got my comp alot of people said the straight cut 100 trim turbine wheel is not good. I never really got a real answer to why. It makes real good power,780whp at 17psi. thats a t4 79mm turbine on stock 241 heads through a locked auto and 9 inch.
#75
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read back on the ITS turbos, these are the same turbines
i am not saying anything bad about them, that is a hell of a compressor on the front
and you will make more power and boost, it will just take more pressure on top of the gate than it did before
again it just sounds like higher drive pressure by what u describe
stickyour gauge back on and report back, then we will know
i am not saying anything bad about them, that is a hell of a compressor on the front
and you will make more power and boost, it will just take more pressure on top of the gate than it did before
again it just sounds like higher drive pressure by what u describe
stickyour gauge back on and report back, then we will know
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Spayed01 had the 79mm Comp turbine on a billet 80mm wheel on 6.0 -didn't work!
Comp swapped to the cast 80mm wheel (-200HP) and he gets about 5300rpm at 17psi out of it. He has a short DP IIRC.
Kurt Urban came on the thread and said (short version) the issue was the turbine and he won't use that turbine.
A billet wheel will flow more than cast of same size. But it will take a bigger turbine or more BPR to turn than higher flowing compressor.
PT88's exhibt similar behavior on a 6.0 at 19 psi or so.
7675's do similar on 350's at 5k and 17 or so psi
Comp swapped to the cast 80mm wheel (-200HP) and he gets about 5300rpm at 17psi out of it. He has a short DP IIRC.
Kurt Urban came on the thread and said (short version) the issue was the turbine and he won't use that turbine.
A billet wheel will flow more than cast of same size. But it will take a bigger turbine or more BPR to turn than higher flowing compressor.
PT88's exhibt similar behavior on a 6.0 at 19 psi or so.
7675's do similar on 350's at 5k and 17 or so psi
#77
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Well here's the update: the highest temp today was 108 degrees, so not too good to start. The car made good power in the lower settings, and it seemed like the boost came in quicker and didn't drop off as bad in the upper rpm's. When we tried the high boost setting (17psi) it would only make about 14lbs. It was making about 850rwhp and increasing the boost controller even wouldn't up the boost. The car was getting really hot, so we cooled it down and tried again with no luck. I ended up taking it home without figuring it out. I checked for boost leaks but couldn't find any....
Any ideas guys?
Any ideas guys?
Does your wastegate dump to atmosphere or re-circ back into the exhaust ? If the latter, could you easily re-configure it to vent to atmos so you can see/hear if the w/g is not sealing correctly ?
Or a w/g like this can make an awful lot of sense.
http://www.fastmotorsports.com/produ...wastegates.htm
#78
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Spayed01 had the 79mm Comp turbine on a billet 80mm wheel on 6.0 -didn't work!
Comp swapped to the cast 80mm wheel (-200HP) and he gets about 5300rpm at 17psi out of it. He has a short DP IIRC.
Kurt Urban came on the thread and said (short version) the issue was the turbine and he won't use that turbine.
A billet wheel will flow more than cast of same size. But it will take a bigger turbine or more BPR to turn than higher flowing compressor.
PT88's exhibt similar behavior on a 6.0 at 19 psi or so.
7675's do similar on 350's at 5k and 17 or so psi
Comp swapped to the cast 80mm wheel (-200HP) and he gets about 5300rpm at 17psi out of it. He has a short DP IIRC.
Kurt Urban came on the thread and said (short version) the issue was the turbine and he won't use that turbine.
A billet wheel will flow more than cast of same size. But it will take a bigger turbine or more BPR to turn than higher flowing compressor.
PT88's exhibt similar behavior on a 6.0 at 19 psi or so.
7675's do similar on 350's at 5k and 17 or so psi
#79
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First things first. Ensure your wastegate is working and sealing correctly. And as you have changed the turbo, which is a huge change, the settings on your Eboost from before will not be the same.
Does your wastegate dump to atmosphere or re-circ back into the exhaust ? If the latter, could you easily re-configure it to vent to atmos so you can see/hear if the w/g is not sealing correctly ?
Or a w/g like this can make an awful lot of sense.
http://www.fastmotorsports.com/produ...wastegates.htm
Does your wastegate dump to atmosphere or re-circ back into the exhaust ? If the latter, could you easily re-configure it to vent to atmos so you can see/hear if the w/g is not sealing correctly ?
Or a w/g like this can make an awful lot of sense.
http://www.fastmotorsports.com/produ...wastegates.htm
I just found this however:
![](http://i128.photobucket.com/albums/p173/xjjf1015x/photo-1.jpg)
i went to home depot and made a pressure tester. I couldnt even get it to fill past 10psi. the t-bolt strap deformed my tube that goes into the throttle body. It was leaking quite a bit. Would this cause my issue? Ive never had a slow & steady leak like this, only time I had a leak was when the hose would blow all the way off...
what do you think?
Last edited by KILLER-LS1; 08-09-2012 at 08:45 PM.
#80
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You were on a dyno...couldnt you feel the leak ? Im amazed that pipe even stayed on, it is pretty bad.
It certainly wouldnt have helped matters at all, the turbo would have been working very hard to try and ovecome the leak.
Turbo speed sensor is worthwhile to monitor that type of thing too.
I always prefer stainless for boost pipes, zero chance of them deforming.
Alloy is just very soft. Before I fitted the external throttle return springs on my TB even it was sticking slightly when I tightened up my boost pipe onto it ! It's amazing the pressure some hose clamps can exert.
It certainly wouldnt have helped matters at all, the turbo would have been working very hard to try and ovecome the leak.
Turbo speed sensor is worthwhile to monitor that type of thing too.
I always prefer stainless for boost pipes, zero chance of them deforming.
Alloy is just very soft. Before I fitted the external throttle return springs on my TB even it was sticking slightly when I tightened up my boost pipe onto it ! It's amazing the pressure some hose clamps can exert.