UPDATED!!*DYNO NUMBERS* Comparison of Comp Turbo Billet 88mm CT6X-88 & GT91 Garrett!!
08-09-2012, 03:10 PM
#81
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.
youre right, I never realized how tight those clamps get.. I straightened it out and tried the pressure test again. I made enough pressure to blow up the 5" plug covering the turbo inlet... now I cant find another 5" plug anywhere to keep testing
08-09-2012, 03:57 PM
#82
9 Second Club
Blowing up a plug is one thing...it's when it blows out is another !! Can go with one hell of a bang.
I'm not even using T-bolts anymore and the clamp was able to distort the TB !
You know the compressor itself is sealed, so just remove a pipe off the turbo and test from that point.
I'm not even using T-bolts anymore and the clamp was able to distort the TB !
You know the compressor itself is sealed, so just remove a pipe off the turbo and test from that point.
08-09-2012, 04:06 PM
#84
9 Second Club
If the T bolts are working, just use them, But dont go nuts tightening them
I'm now using the Breeze Constant Torque clamps. For no other reason than wanted a change. The T-bolts I had were also at the upper limit of their size so sometimes a pain to put on. Next size up was too big.
The Murray clamps above are popular and do work well too.
I'm now using the Breeze Constant Torque clamps. For no other reason than wanted a change. The T-bolts I had were also at the upper limit of their size so sometimes a pain to put on. Next size up was too big.
The Murray clamps above are popular and do work well too.
08-09-2012, 06:08 PM
#86
well I went out and drove it, still not making full boost, but its hard to tell driving it on the crowded streets without getting pulled over.
I hooked up the backpressure line to my analog boost gauge. I set the Eboost2 to read peak boost recall. Heres the results:
over 30+ psi of backpressure to 11.8psi boost pressure. You guys were right. I talked to comp and they said that they think the turbo is being over-spun, creating the backpressure.
apparently putting a bigger compressor wheel exducer will help this? this is getting beyond my expertise here, Im im not sure what to think anymore. He assured me that the new turbine wheel in not flowing less, but it is spinning so fast, thats its creating a restriction.
I hooked up the backpressure line to my analog boost gauge. I set the Eboost2 to read peak boost recall. Heres the results:
over 30+ psi of backpressure to 11.8psi boost pressure.
You guys were right. I talked to comp and they said that they think the turbo is being over-spun, creating the backpressure.apparently putting a bigger compressor wheel exducer will help this? this is getting beyond my expertise here, Im im not sure what to think anymore. He assured me that the new turbine wheel in not flowing less, but it is spinning so fast, thats its creating a restriction.
08-09-2012, 06:52 PM
#87
what a bunch of bullshit man, i am sorry to be right
.
they are giving you the runaround /story
tell them you want your money back
all the people that butt hump Comp are small displacement guys
it would be interesting to see that compressor paired to your old turbine
.
they are giving you the runaround /story
tell them you want your money back
all the people that butt hump Comp are small displacement guys
it would be interesting to see that compressor paired to your old turbine
08-09-2012, 07:11 PM
#88
On The Tree
Join Date: Mar 2011
Posts: 106
Likes: 0
Received 0 Likes
on
0 Posts
Well thats some shitty luck.
See if you can get a larger exducer on your compressor wheel. That should slow it down and allow you to create more boost pressure.
Also I noticed your compressor wheel has 7 blades. Maybe swap to the 6 blade design as some compensation for the upset.
http://www.compturbo.com/spotlights/largewheel
See if you can get a larger exducer on your compressor wheel. That should slow it down and allow you to create more boost pressure.
Also I noticed your compressor wheel has 7 blades. Maybe swap to the 6 blade design as some compensation for the upset.
http://www.compturbo.com/spotlights/largewheel
08-09-2012, 07:13 PM
#89
Launching!
Join Date: May 2004
Posts: 266
Likes: 0
Received 0 Likes
on
0 Posts
See if u can get them to swap out to a 1.32 housing of u wanna see if it helps, but the turbine does look to be the issue ...or send it back to fix the turbine (downtime sucks), they should fix it... Some times FI sucks.
08-09-2012, 07:20 PM
#90
On The Tree
Join Date: Mar 2011
Posts: 106
Likes: 0
Received 0 Likes
on
0 Posts
Thats a large turbine wheel. Either it just sucks shiz (which I find hard to believe) or the turbo is spinning too fast which means a larger exducer is needed on the compressor wheel. I actually missed Killer-LS1 said the larger exducer, forgive me for repeating it.
08-09-2012, 07:40 PM
#91
even if it is a simple "mismatch" which i doubt...... there is NO excuse for it
who lets combos like that out the door?
that is twice just here that has happened
they may be good on a cnc machine and putting fancy stuff together but their R&D department is non existent
they better be covering shipping too
look at the BW stuff.... you can mix and match a 96mm turbine with a huge varitey of compressor sizes and do they have this?? uhhhhhhhh no
get your money back and put on a proven combo
who lets combos like that out the door?
that is twice just here that has happened
they may be good on a cnc machine and putting fancy stuff together but their R&D department is non existent
they better be covering shipping too
look at the BW stuff.... you can mix and match a 96mm turbine with a huge varitey of compressor sizes and do they have this?? uhhhhhhhh no
get your money back and put on a proven combo
08-09-2012, 07:59 PM
#92
I just dont comprehend how a larger compressor wheel exducer will slow down a turbo and relieve backpressure....
a larger wheel will flow more air. more air in the cylinder and more air in the exhaust. more exhaust means more drive pressure. more drive pressure = faster shaft speed. Do have this wrong?
The owner actually just called me and this makes a lot more sense now. He thinks the A/R sizing is too small. He said that since the compressor wheel is flowing so much more air, (due to lightweight wheel spinning faster and billet flowing more) that the exhaust housing has now become a restriction. He wants me to change from the 1.08 A/R to a 1.23 or 1.23 a/r.
Now this makes much more sense to me, and I can actually believe that. What do you guys think?
a larger wheel will flow more air. more air in the cylinder and more air in the exhaust. more exhaust means more drive pressure. more drive pressure = faster shaft speed. Do have this wrong?
The owner actually just called me and this makes a lot more sense now. He thinks the A/R sizing is too small. He said that since the compressor wheel is flowing so much more air, (due to lightweight wheel spinning faster and billet flowing more) that the exhaust housing has now become a restriction. He wants me to change from the 1.08 A/R to a 1.23 or 1.23 a/r.
Now this makes much more sense to me, and I can actually believe that. What do you guys think?
08-09-2012, 08:00 PM
#93
TECH Apprentice
Join Date: Mar 2012
Location: Aus
Posts: 303
Likes: 0
Received 0 Likes
on
0 Posts
Eeeehhhhh leaning away from comp.... After being told a 8082 or twin 62's will make 1100rwhp on a 398 by their "tech" guy and now this...
Might just bite the bullet and send some money to NRE for their twins.
Might just bite the bullet and send some money to NRE for their twins.
08-09-2012, 08:04 PM
#94
FormerVendor
I think a larger exhaust a/r will do nothing to help the problem.
You need to either have a much smaller compressor wheel for your current turbine, or better yet, a much higher flowing turbine for your current compressor wheel.
The turbine is a mismatch and doesn't easily generate the required torque to drive the compressor = tons of backpressure.
As mentioned, go ahead and measure it, you will probably look like this afterwords-
exhaust a/r will not fix that.
You need to either have a much smaller compressor wheel for your current turbine, or better yet, a much higher flowing turbine for your current compressor wheel.
The turbine is a mismatch and doesn't easily generate the required torque to drive the compressor = tons of backpressure.
As mentioned, go ahead and measure it, you will probably look like this afterwords-
exhaust a/r will not fix that.
08-09-2012, 08:05 PM
#95
even if it is a simple "mismatch" which i doubt...... there is NO excuse for it
who lets combos like that out the door?
that is twice just here that has happened
they may be good on a cnc machine and putting fancy stuff together but their R&D department is non existent
they better be covering shipping too
look at the BW stuff.... you can mix and match a 96mm turbine with a huge varitey of compressor sizes and do they have this?? uhhhhhhhh no
get your money back and put on a proven combo
who lets combos like that out the door?
that is twice just here that has happened
they may be good on a cnc machine and putting fancy stuff together but their R&D department is non existent
they better be covering shipping too
look at the BW stuff.... you can mix and match a 96mm turbine with a huge varitey of compressor sizes and do they have this?? uhhhhhhhh no
get your money back and put on a proven combo
08-09-2012, 08:06 PM
#96
On The Tree
Join Date: Mar 2011
Posts: 106
Likes: 0
Received 0 Likes
on
0 Posts
Damn you were on a 1.08. I thought you were on a 1.25 or something in that neighbourhood. Yes you could have high bp with the newer wheels.
To answer your question with the exducers on the compressor. Think boat propellers. You put a larger propeller you will get an bigger initial push but it will move slower. If you have a small propeller it spins quicker than the same one with the larger exducer. I was thinking this for your case but you have a small housing.
If its not the housing then its the boat propeller thats the prob.
Since you spoke with the owner when will you get new housings?
To answer your question with the exducers on the compressor. Think boat propellers. You put a larger propeller you will get an bigger initial push but it will move slower. If you have a small propeller it spins quicker than the same one with the larger exducer. I was thinking this for your case but you have a small housing.
If its not the housing then its the boat propeller thats the prob.
Since you spoke with the owner when will you get new housings?
08-09-2012, 08:10 PM
#97
I think a larger exhaust a/r will do nothing to help the problem.
You need to either have a much smaller compressor wheel for your current turbine, or better yet, a much higher flowing turbine for your current compressor wheel.
The turbine is a mismatch and doesn't easily generate the required torque to drive the compressor = tons of backpressure.
As mentioned, go ahead and measure it, you will probably look like this afterwords- exhaust a/r will not fix that.
You need to either have a much smaller compressor wheel for your current turbine, or better yet, a much higher flowing turbine for your current compressor wheel.
The turbine is a mismatch and doesn't easily generate the required torque to drive the compressor = tons of backpressure.
As mentioned, go ahead and measure it, you will probably look like this afterwords-
exhaust a/r will not fix that.
08-09-2012, 08:17 PM
#98
On The Tree
Join Date: Mar 2011
Posts: 106
Likes: 0
Received 0 Likes
on
0 Posts
Maybe you can put a sheild of some sort between the housing and the rad? Maybe a turbo blanket?
Good thing you are local, grab those new housings and pop them on and see.
When you think you will hit the dyno again or will you get a bpr from the street?
Good thing you are local, grab those new housings and pop them on and see.
When you think you will hit the dyno again or will you get a bpr from the street?
08-09-2012, 08:26 PM
#99
I hate to say this and hope I am wrong for your sake, but bolt the gt91 back on there. You spend a lot of money on this turbo and it doesnt seem to be making what you want. If you swap exhaust housings and it doesnt make more than 1000hp to the wheels on 17psi then I would give it back to them. A $1300 gt91 did and this is a $3000 comp.
08-09-2012, 08:32 PM
#100
I hate to say this and hope I am wrong for your sake, but bolt the gt91 back on there. You spend a lot of money on this turbo and it doesnt seem to be making what you want. If you swap exhaust housings and it doesnt make more than 1000hp to the wheels on 17psi then I would give it back to them. A $1300 gt91 did and this is a $3000 comp.
I will not be buying from forced inductions again, and otherwise i'd buy a precision, but ive been hearing some bad things recently about their stuff. Why cant anyone just build a nice turbo, with no issues?
