Slow spool
Slow spool Hey guys, had the car out a few times and seem to be having an issue. Have a 76mm turbo with a 44mm TS Hypergate and boost is coming on ridiculously slow. Doesn't start to build until 3500-4000rpm and I have to shift before I even see the full 7psi from the WG spring. My first thought was an exhaust leak, but it would have to be a pretty extreme exhaust leak!
Wastegate would be a possibility as well but I'm more concerned about the turbo. The turbine seems to have a pretty noticeable "squeek" like it isn't getting enough oil to it. That would be my only other thought as if the turbine isn't turning like it should, it would probably be a safe guess that it would hurt my spool time.
Am I off the mark on my thinking? Any opinions or thoughts would be appreciated.
Wastegate would be a possibility as well but I'm more concerned about the turbo. The turbine seems to have a pretty noticeable "squeek" like it isn't getting enough oil to it. That would be my only other thought as if the turbine isn't turning like it should, it would probably be a safe guess that it would hurt my spool time.
Am I off the mark on my thinking? Any opinions or thoughts would be appreciated.
Couple questions to help diagnose the problem...
What gears are you running in the rear?
Are you hitting 7psi (WG spring pressure) in higher gears?
Are you referencing your boost from the compressor or the intake manifold?
How much restriction do you have in your exhaust (post turbo)?
What gears are you running in the rear?
Are you hitting 7psi (WG spring pressure) in higher gears?
Are you referencing your boost from the compressor or the intake manifold?
How much restriction do you have in your exhaust (post turbo)?
To check if your turbo is getting proper oil amounts, I'd mount a tee fitting right by where the feed line attachs to the turbo and get an oil pressure gauge. Also, do a boost leak test. You might be leaking air from somewhere in the charge piping.
Couple questions to help diagnose the problem...
What gears are you running in the rear?
Are you hitting 7psi (WG spring pressure) in higher gears?
Are you referencing your boost from the compressor or the intake manifold?
How much restriction do you have in your exhaust (post turbo)?
What gears are you running in the rear?
Are you hitting 7psi (WG spring pressure) in higher gears?
Are you referencing your boost from the compressor or the intake manifold?
How much restriction do you have in your exhaust (post turbo)?
I haven't tested pressure in higher gears. So far I've only gone to boost in 1st and 2nd. I'll take it out for a drive later and try it out in 3rd and maybe 4th. 4th might be scary. This thing pulls like a raped ape once the boost comes on!
Boost reference to the wastegate comes from the compressor. There is also a manual boost controller in there. Maybe I'll try taking that out of the equation and seeing what happens? I have a vacuum distribution block referenced from the manifold that I could use if you think I should.
Post turbo I have a 3" downpipe running to a Magnaflow catback. There is also a cutout, and when I drove around the other day with the cutout open there was no real difference in when boost came on.
I really appreciate your time man
I did check for a boost leak earlier and didn't see any bad couplers or anything like that.
As said above, check all the connections, id fashion and air test cap for it from a pvc cap of sorts and block off the opening to the turbo.
When i couldnt build boost with my 7mm Tnetics, it was becuase of two things, my vbands didnt seal worth a **** and the exhaust i had after it sucked ***. Even with the cutout open, it still sucked.
What are you running for a filter? that makes a pretty large difference as well.
When i couldnt build boost with my 7mm Tnetics, it was becuase of two things, my vbands didnt seal worth a **** and the exhaust i had after it sucked ***. Even with the cutout open, it still sucked.
What are you running for a filter? that makes a pretty large difference as well.
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I'm running stock gears. 3.43's I believe.
I haven't tested pressure in higher gears. So far I've only gone to boost in 1st and 2nd. I'll take it out for a drive later and try it out in 3rd and maybe 4th. 4th might be scary. This thing pulls like a raped ape once the boost comes on!
Boost reference to the wastegate comes from the compressor. There is also a manual boost controller in there. Maybe I'll try taking that out of the equation and seeing what happens? I have a vacuum distribution block referenced from the manifold that I could use if you think I should.
Post turbo I have a 3" downpipe running to a Magnaflow catback. There is also a cutout, and when I drove around the other day with the cutout open there was no real difference in when boost came on.
I really appreciate your time man
I haven't tested pressure in higher gears. So far I've only gone to boost in 1st and 2nd. I'll take it out for a drive later and try it out in 3rd and maybe 4th. 4th might be scary. This thing pulls like a raped ape once the boost comes on!
Boost reference to the wastegate comes from the compressor. There is also a manual boost controller in there. Maybe I'll try taking that out of the equation and seeing what happens? I have a vacuum distribution block referenced from the manifold that I could use if you think I should.
Post turbo I have a 3" downpipe running to a Magnaflow catback. There is also a cutout, and when I drove around the other day with the cutout open there was no real difference in when boost came on.
I really appreciate your time man
It's especially bad for me in 1st gear with my 4.11's (changing soon).It's fine to reference the boost for your WG at the compressor but you should expect less peak boost than if you referenced it at the manifold (due to losses in the I/C, etc). Since you have a boost controller you can easily make up the difference...No need to change the location.
I run 3" pipe from my turbo dumped behind the k-member. Any restrictions post turbo will affect spool. I suggest you remove your exhaust after the downpipe just for a test to see if that makes any difference...I'm guessing you will probably leave it off after you try it :p I love the way it sounds!
One final thought I had is wrapping/blanket. If you don't already, I would wrap your crossover and put a blanket on the turbo to retain heat for a faster spool. I've always had mine this way so I don't have a good comparison but most people claim it's very noticeable.
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What are you running for a filter? that makes a pretty large difference as well.
When i couldnt build boost with my 7mm Tnetics, it was becuase of two things, my vbands didnt seal worth a **** and the exhaust i had after it sucked ***. Even with the cutout open, it still sucked.
Did you install the valve seat in the gate?
It is worth mentioning that my stupid *** dropped the wastegate 8 feet down onto concrete in my pit when I was taking it off one time. The housing seems fine though and I didn't see any noticeable damage.
Those of us with a manual trans are at a disadvantage for spool...normally geared more (less load on engine) and we lose boost during shifts. My TC78 doesn't spool very well in first gear but once I shift to 2nd or 3rd I am always at full boost almost instantly. I suspect that once you start hitting the higher gears you wont care about the delay in first gear It's especially bad for me in 1st gear with my 4.11's (changing soon).
It's fine to reference the boost for your WG at the compressor but you should expect less peak boost than if you referenced it at the manifold (due to losses in the I/C, etc). Since you have a boost controller you can easily make up the difference...No need to change the location.
I run 3" pipe from my turbo dumped behind the k-member. Any restrictions post turbo will affect spool. I suggest you remove your exhaust after the downpipe just for a test to see if that makes any difference...I'm guessing you will probably leave it off after you try it :p I love the way it sounds!
One final thought I had is wrapping/blanket. If you don't already, I would wrap your crossover and put a blanket on the turbo to retain heat for a faster spool. I've always had mine this way so I don't have a good comparison but most people claim it's very noticeable.
You know you're an FI noob when it takes you about a half hour of searching for "wastegate valve seat" on google to figure out what exactly it is and then another 2 hours for you to think to yourself....
"HEY DUMBASS! REMEMBER THOSE TWO ROUND RINGS THAT WERE LEFT IN THE TURBOSMART BOX THAT YOU DIDN'T THINK YOU NEEDED????"
I would like that think that any complete dumbass could have mistaken them for flanges
Thank you to everyone here for helping me out. And a big thank you to Marty and LS1nova for gradually assisting me in pulling my head out of my ***.
"HEY DUMBASS! REMEMBER THOSE TWO ROUND RINGS THAT WERE LEFT IN THE TURBOSMART BOX THAT YOU DIDN'T THINK YOU NEEDED????"
I would like that think that any complete dumbass could have mistaken them for flanges
Thank you to everyone here for helping me out. And a big thank you to Marty and LS1nova for gradually assisting me in pulling my head out of my ***.
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You know you're an FI noob when it takes you about a half hour of searching for "wastegate valve seat" on google to figure out what exactly it is and then another 2 hours for you to think to yourself....
"HEY DUMBASS! REMEMBER THOSE TWO ROUND RINGS THAT WERE LEFT IN THE TURBOSMART BOX THAT YOU DIDN'T THINK YOU NEEDED????"
I would like that think that any complete dumbass could have mistaken them for flanges
Thank you to everyone here for helping me out. And a big thank you to Marty and LS1nova for gradually assisting me in pulling my head out of my ***.
"HEY DUMBASS! REMEMBER THOSE TWO ROUND RINGS THAT WERE LEFT IN THE TURBOSMART BOX THAT YOU DIDN'T THINK YOU NEEDED????"
I would like that think that any complete dumbass could have mistaken them for flanges
Thank you to everyone here for helping me out. And a big thank you to Marty and LS1nova for gradually assisting me in pulling my head out of my ***.
Got the seat in tonight. It was DEFINITELY the problem. Went from starting boost at 3500rpm to full boost at 4000rpm. This thing runs like it was set on fire. Thank you again for the help guys.
The difference was unbelievable. I was pretty disappointed the first time out without the seat thinking this might just be part of the "turbo lag", but I never would have thought that such a small part could let so much exhaust escape. Starting to think that the still smoking hole in my wallet may have been worth it