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Discussion Starter · #1 ·
What psi would I be able to run a pte 6765 on stock fuel and tune to be safe. Not tuning for power until installing a new fuel system. But I'm a solid beleiver in changing as few things as I can at a time to help diagnose possible issues that come up. So going single first. Tuning and running that way for a little. Then adding fuel later.

As these turbos are making 750/850 when pushing 25 to 28 psi from what I've read. I'm wondering what psi I would need to run in order to keep it below 550hp and retain stock fuel system until I'm comfortable with a big upgrade
 

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Great question. I would like to know this as well.
 

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Boost Dealer
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I'm planning on starting at 8psi, and slowly working myself up to where I'm comfortable and A/F settle at 11.2-11.4. Then leaving it there until I get my new injectors.

Jeff
 

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I don't know about that much hp on that level of boost. I was just helping tune Dre's (dre99gsx) supra last week. He has the 6768 billet (larger than the 6765) and he was running 32psi probably making upwards of 750-800 rwhp on pump/meth.

The billets are nice in the high psi range. I would simply use your AFR's as your guide to keep things at "safe levels" and keep it under 18psi. You should be fine.
 

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Probably 13-14psi to be safe. I am making 525whp with a 6265 at 17psi
 

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He has the 6768 billet (larger than the 6765) and he was running 32psi probably making upwards of 750-800 rwhp on pump/meth.
32psi on pump and meth? That's insane.........and no I'm not calling you insane, that just seems like a lot of boost. Are you using 93 octane? What mixture of meth and water, if any?
I've been running 24psi on my pump and meth, but I think I'll go up to 26psi since I've been reading about other guys running 29psi on 74mm turbo's with meth and pump. Do you know what size nozzle he uses?

Sorry for the thread jack
 

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32psi on pump and meth? That's insane.........and no I'm not calling you insane, that just seems like a lot of boost. Are you using 93 octane? What mixture of meth and water, if any?
I've been running 24psi on my pump and meth, but I think I'll go up to 26psi since I've been reading about other guys running 29psi on 74mm turbo's with meth and pump. Do you know what size nozzle he uses?

Sorry for the thread jack
100 sunoco, 50/50 mix i believe. AFR's were around 11.8-12.0, virtually no knock. As for as the nozzles, honestly not sure on the exact size. PM Dre99gsx as I'm sure he'll be able to fill you in on that info.
 

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Discussion Starter · #10 ·
sounds good. id love to pick up all that i need as soon as possible too, good to know it shouldnt be too difficult to keep it tame until im ready for the big time
 

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adammackintosh.net
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just make sure your wastegate setup will handle that boost without overshooting horribly :)
 

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What psi would I be able to run a pte 6765 on stock fuel and tune to be safe. Not tuning for power until installing a new fuel system. But I'm a solid beleiver in changing as few things as I can at a time to help diagnose possible issues that come up. So going single first. Tuning and running that way for a little. Then adding fuel later.

As these turbos are making 750/850 when pushing 25 to 28 psi from what I've read. I'm wondering what psi I would need to run in order to keep it below 550hp and retain stock fuel system until I'm comfortable with a big upgrade
Boost isn't going to be your main concerning factor, power is. The stock fuel system (on a car that is ~15 years old) isn't going to be up to peak performance and isn't always capable of the 500-550whp that everyone claims. For example, muy stock fuel system was at it's limits at 468whp @ 18psi on my 68mm turbo, and that was after my stock Denso pump failed on me (new Walbro was in place). In addition, I had a FPR to bump base pressure to help out those tired old injectors.

So to sum up, you can run a Precision 6765 Billet (assuming you have at least a wideband, some sort of tuning software, and a reliable wastegate/boost controller), get it on the dyno (monitoring fuel pressure and/or injector duty would be most helpful, I had my AEM EMS at the time so was covered) and see what power the car wants to make with thr fuel system limitations. I would imagine you could push somewhere around 14-16psi but like I said, you won't know until you are on the dyno.*

Reid
 

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Heya Reid, on that 6765 billet spool valve setup you guys tested, was that a BB turbo? trying to find the link.

Jeff
 

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32psi on pump and meth? That's insane.........and no I'm not calling you insane, that just seems like a lot of boost. Are you using 93 octane? What mixture of meth and water, if any?
I've been running 24psi on my pump and meth, but I think I'll go up to 26psi since I've been reading about other guys running 29psi on 74mm turbo's with meth and pump. Do you know what size nozzle he uses?
Boost isn't really the factor, it's timing. There are plenty of people running 28psi on straight pump - the Euro guys do it pretty often. Just don't expect to see 18 or 19 degrees in the logs. As long as you've got enough fuel, just back the timing down to 8 degrees and you're all set. :)

Not saying I'm doing that with MY car, but nonetheless it can be done. But with Dre's numbers, it sure seems like there shouldn't be much left on the table.
 

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I'm running a 1200cc nozzle with a 50/50 mixture and run 16 degrees with 25psi. Not sure of the URL, but there is an alcohol injection size calculator that takes your input parameters and spits out the nozzle size requirement.
 

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My guess would be 14-15 psi just to be safe on stock fuel...
 
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