high drive pressure question
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From: Texas/Oklahoma Border
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From: McDonough GA
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From: SoCal
I just got my TST on today and my drive pressure gauge as well. I went out testing after it was all on. With my HTT 64/65/13ss and the Smarty on 8/wild torque management and TST with timing/pressure, I was hitting 42-46 lbs of boost with spikes up to 48lbs. The drive pressure was hitting 55-60lbs commonly with spikes up to 65lbs. With just the smarty, the turbo only hits 38lbs. In reality, how bad are these drive pressure ratios? I had planned on studs in the future, but am I likely going to blow the head gasket at these ratios? No nitrous or water/meth. All opinions welcome. Thanks Tac.
How different would these be w/just the Smarty and no TST?
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From: Pattonville, Texas
Lloyd, sounds like you've tested HE351s too! 
Keegan - we've been monitoring drive pressure and boost VS. intake differential and pre-CAC temps on our '05 for the last 30K miles... you definitely will need a 0-100psi boost gauge for a TIP kit (it's way too easy to wind up the 0-60psi!).
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From: Florida
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From: Kingsport, TN
i'll turn the tst off and see what the drive pressures look like. I did talk to HTT today about it. They said I need to turn the fuel down to get the pressures back down. They said I could send in and upgrade to a 71 wheel but the towing would be affected. I asked about going to a larger exhaust housing, and they said that they haven't done any 16 ss with the 65 wheel and it would hurt bottom end. They also said that I need an intercooler to help raise the boost and make the turbo more efficient in order to help drop the drive pressures. I absolutely love how this turbo drives. With the ported, polished, and ceramic coated ATS manifold, it spools great. I just don't know what route I want to go. Will just adding head studs be the best resolution to the problem and leave everything as is? 
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From: CHAMPAIGN ILLINOIS
This is just a question, but actually on a single turbo wouldn't it be better to have 5 to 10 lbs more dp than boost to keep the turbo spooled? I have heard this from some other guys because they say you have to have more dp to keep the turbo producing optimum boost. If that was true then his numbers would be abought right. Tim
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This is just a question, but actually on a single turbo wouldn't it be better to have 5 to 10 lbs more dp than boost to keep the turbo spooled? I have heard this from some other guys because they say you have to have more dp to keep the turbo producing optimum boost. If that was true then his numbers would be abought right. Tim
A 1:1 ratio is when the turbo will be at it's optimum efficiency range. That's not to say you can't safely squeeze a little more out of them, but you will lose efficiency as the DP goes up.
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From: Applegate, CA
i'll turn the tst off and see what the drive pressures look like. I did talk to HTT today about it. They said I need to turn the fuel down to get the pressures back down. They said I could send in and upgrade to a 71 wheel but the towing would be affected. I asked about going to a larger exhaust housing, and they said that they haven't done any 16 ss with the 65 wheel and it would hurt bottom end. They also said that I need an intercooler to help raise the boost and make the turbo more efficient in order to help drop the drive pressures. I absolutely love how this turbo drives. With the ported, polished, and ceramic coated ATS manifold, it spools great. I just don't know what route I want to go. Will just adding head studs be the best resolution to the problem and leave everything as is?
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From: Applegate, CA
Seriously... you have a nice top turbo. Don't do anything to it; except to put a nice k31 or s400 under it. By the time you monkey around with bigger wheels and this or that to your single, you could just spend a couple more $$ and do it right.
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From: SoCal
i'll turn the tst off and see what the drive pressures look like. I did talk to HTT today about it. They said I need to turn the fuel down to get the pressures back down. They said I could send in and upgrade to a 71 wheel but the towing would be affected. I asked about going to a larger exhaust housing, and they said that they haven't done any 16 ss with the 65 wheel and it would hurt bottom end. They also said that I need an intercooler to help raise the boost and make the turbo more efficient in order to help drop the drive pressures. I absolutely love how this turbo drives. With the ported, polished, and ceramic coated ATS manifold, it spools great. I just don't know what route I want to go. Will just adding head studs be the best resolution to the problem and leave everything as is?
I would really appreciate that Tacsavage. I have been wanting that same turbo (still saving). I don't really plan on getting any fuel boxes. I also just realized how similar our mods are. It will be great information for me.
Thanx.
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From: NW Indiana
Originally posted by Mike aka XLR8R
Tony, you need to back flush the soot filter periodically - a shot of compressed air is the easiest way. The gauge's nylon boost tubing should be filled with carbon/condensate and when the filter's out you ought to blast a shot of air through the stainless steel coils.
Thanks Mike... I didn't think to do this. Guess I have to live with it clogging up quite quickly...
darn soot...
Tony, you need to back flush the soot filter periodically - a shot of compressed air is the easiest way. The gauge's nylon boost tubing should be filled with carbon/condensate and when the filter's out you ought to blast a shot of air through the stainless steel coils.
Thanks Mike... I didn't think to do this. Guess I have to live with it clogging up quite quickly...
darn soot...
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From: Texas/Oklahoma Border
Higher drive pressure is an advantage at low boost... for the reasons you mention. Mid range boost, you want 1:1. Max boost is best when DP is as low as you can get it, in theory.
Unfortunately, what we get is the other way around. My S300 single (previous turbo) was under 1:1 up to 35 psi....1:1 from 40 to 45 psi, and about 1:1.3 above 48 psi.
RJ
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From: CHAMPAIGN ILLINOIS
Thanks for the answers. I didn't want to hijack somebody elses thread, but it seemed to fit in this one pretty good. I was just wondering what some of you guys thought about that situation. I just bought the drive pressure gauge to put in my truck but have not got it installed yet. I am curious to see what mine will run for dp. Tim
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From: Pattonville, Texas
Originally posted by Mike aka XLR8R
Tony, you need to back flush the soot filter periodically - a shot of compressed air is the easiest way. The gauge's nylon boost tubing should be filled with carbon/condensate and when the filter's out you ought to blast a shot of air through the stainless steel coils.
Thanks Mike... I didn't think to do this. Guess I have to live with it clogging up quite quickly... darn soot...
Tony, you need to back flush the soot filter periodically - a shot of compressed air is the easiest way. The gauge's nylon boost tubing should be filled with carbon/condensate and when the filter's out you ought to blast a shot of air through the stainless steel coils.
Thanks Mike... I didn't think to do this. Guess I have to live with it clogging up quite quickly...
darn soot...My TIP kit goes ~ 9 months before it need flushing, but I know heavy chain-smokers are half that...