How quick are PT-88 guys running?
03-08-2006, 08:20 PM
#61
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Originally Posted by JZ 97 SS 1500
Addressing bacpressure starts on the exhaust side. Making the engine breathe even better will make it worse actually. The further the PR gets away from 1:1 the worse it will get and the more hp you will lose.
jose what exactly should i look for to spot backpressure issues?
03-08-2006, 10:34 PM
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Originally Posted by PurEvl
jose what exactly should i look for to spot backpressure issues?
03-09-2006, 12:45 AM
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I think it was Ray Dowdy or something like that who ran a T4 PT88 in the 1st pump gas drags. It was a Nova with a 406 sbc and it went 9.0's on pump gas. I'm sure backpressure would be high but the e.t's are bad ***.
03-09-2006, 09:00 AM
#66
Update: I called Precision and they also recommended a T6 flange for my 408ci. I went ahead and ordered the T6 housing from them, since they said there were only two left on the shelf and aren't making any more for a long time.
This will also make it easier for me to upsize later on, if I wish.
Tony
This will also make it easier for me to upsize later on, if I wish.
Tony
03-09-2006, 09:08 AM
#67
Originally Posted by Nine Ball
Update: I called Precision and they also recommended a T6 flange for my 408ci. I went ahead and ordered the T6 housing from them, since they said there were only two left on the shelf and aren't making any more for a long time.
This will also make it easier for me to upsize later on, if I wish.
Tony
This will also make it easier for me to upsize later on, if I wish.
Tony
Good call.........
03-09-2006, 09:51 AM
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Originally Posted by JZ 97 SS 1500
High EGT's and header gaskets popping out are easy signs....hehe.
Time will tell
03-09-2006, 09:52 AM
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Originally Posted by dynedta
purevl you could always tap the exhaust pipe going to the turbo and put a gauge on it to see where your at
03-09-2006, 02:22 PM
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Yeah the T6 makes more sense if you plan to try to max out that turbo. Backpressure is going to make it's presence known if you start frying header gaskets and stuff is cracking.
Jose, any pics of an S88 mounted in car? How about that mystery car in California? You're a tease, let's see a pic or hear more info. I'm starting to think that the turbo is in some diesel truck.
Jose, any pics of an S88 mounted in car? How about that mystery car in California? You're a tease, let's see a pic or hear more info. I'm starting to think that the turbo is in some diesel truck.
03-09-2006, 02:40 PM
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Haha. Measure the backpressure to on the mystery car. I found that the folks at Precision did not agree with you about how high the backpressure is with a 47-88 used on a 327-360ci engine.
03-09-2006, 03:08 PM
#73
Update 2:
Precision called back and said that I would need a new turbine in order to swap housings to T6. The upgrades would cost around $400. Suddenly, the T4 housing seems more desirable to me.
Hmmm, anyone want to buy a brand new PT88/T4? Retail is $1699, make an offer via PM
Precision called back and said that I would need a new turbine in order to swap housings to T6. The upgrades would cost around $400. Suddenly, the T4 housing seems more desirable to me.
Hmmm, anyone want to buy a brand new PT88/T4? Retail is $1699, make an offer via PM
03-09-2006, 03:15 PM
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Originally Posted by Pro Stock John
Haha. Measure the backpressure to on the mystery car. I found that the folks at Precision did not agree with you about how high the backpressure is with a 47-88 used on a 327-360ci engine.
A thumper hitting 2:1 is not great.
Also as mentioned before, 402 LS1 with S88 at 18psi was 39psi.
360 with GT47-85 at 20psi was around 48psi.
I'll dig up some new logs we have from a 331 windsor and GT47-88. I will send you a copy
. The numbers don't lie . Now the GT47 did outperform the Y2K-88 though. Also its spooled only about 200 rpms sooner then the 47, so that is nice.
03-09-2006, 03:32 PM
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The car is now running a GT55-88mm with a 1.00 A/R. 18psi gave 32psi BP and 7800rpms . We have data for almost every damn turbo out there....lol. In some form or fashion.....hehe
BTW, the GT55 is what I would have gone with for your combo. Only spools 200 rpms slower.
PS. We pride ourselves in being independent in turbo testing. We don't really care what we sell (brand wise) as long as it works. Garrett is better for somethings and then not so hot for others....the same goes for the other manufactures.
. We have data for almost every damn turbo out there....lol. In some form or fashion.....heheBTW, the GT55 is what I would have gone with for your combo. Only spools 200 rpms slower.
PS. We pride ourselves in being independent in turbo testing. We don't really care what we sell (brand wise) as long as it works. Garrett is better for somethings and then not so hot for others....the same goes for the other manufactures.
03-16-2006, 11:06 PM
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for my 408 @ 8.5:cr, precision recommended a GR45-78 with a T4 flange. This is probably because I'm trying to get away with using the Livernois kit which is setup for a T4. Anyone have any thoughts on that? Any reason why I shouldn't just buy nineball's pt-88 and copy Purevil's setup?