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Discussion Starter #1 (Edited)
I've owned my Supra for 15 years and took it to the dyno for the first time and was kind of disappointed with the numbers.
Best I could do was 499.22HP on 19PSI. I know there are many different setups but I was expecting to get somewhere in the 550 range
Fuel pressure was starting to drop at 17-18PSI and tuner thinks it's a voltage issue. also the wastegate is super old and I am going to change it out to a Tial 50mm or equivalent. I am hoping the numbers will be better once I correct the fuel and wastegate issues but curious to know what everybody thinks I should be getting on pump 18-20psi

Here's my Setup.

93 Octane Fuel
Fully Built GTE
Eagle Rods, JE Pistons
Fully built head, +1mm Oversized Supertech Valves& dual springs, HKS 272 Cams
Precision 6766 JB Turbo
ProEFI 128 Management, 5Bar Map,Mac Boost Solinoid,LSU 02 sensor
HKS 50mm 4 Bolt Wastegate, 10PSI Spring
Suprastore Pro Series Mid Frame T4 Manifold
FIC 1000cc Injectors
TI Automotive 450lph Pump
Stock JDM Manifold&TB
Stock V160, Southbend OFE 3 Clutch, OS Giken Superlock LSD.
 

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Was this on pump fuel 93 octane or Ethanol blend? If 93, your numbers are about right since you don't have higher compression. I have a similar set up-fully built motor but 10/1 compression and S1 cams instead of HKS 272s. It made 480whp at 12.6psi on 93 octane. Keep in mind the extra compression gave me roughly 8-10% more power across the board, so that drops to 420-430ishwhp with the stock compression. Guess, what-get rid of that 93 octane and add ethanol to the mix and we picked up 80whp just by adding timing (560whp at the same 12.6psi). At 19psi it made 650whp on 83% ethanol and keep in mind, compression, compression, compression! We maxed it out at 930whp at 38psi.

I'd do a boost leak test to be sure, but your numbers sound about right to me on stock compression.

Steve

Steve
 

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Discussion Starter #3 (Edited)
Was this on pump fuel 93 octane or Ethanol blend? If 93, your numbers are about right since you don't have higher compression. I have a similar set up-fully built motor but 10/1 compression and S1 cams instead of HKS 272s. It made 480whp at 12.6psi on 93 octane. Keep in mind the extra compression gave me roughly 8-10% more power across the board, so that drops to 420-430ishwhp with the stock compression. Guess, what-get rid of that 93 octane and add ethanol to the mix and we picked up 80whp just by adding timing (560whp at the same 12.6psi). At 19psi it made 650whp on 83% ethanol and keep in mind, compression, compression, compression! We maxed it out at 930whp at 38psi.

I'd do a boost leak test to be sure, but your numbers sound about right to me on stock compression.

Steve

Steve
93 Octane Fuel, sorry I will fix the OP, stock compression JE pistons and an OEM TT Headgasket so I think your on to something, Tuner said he could probably get 550 when I fix the Fuel Pressure issue.
I see posts all the time with people with similar Turbo setups making high 500's at 18-20psi? maybe thats what I was expecting

do you have to run E85 for 10-1 compression? I would run E85 if there was a station within 100 miles of me.
 

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Discussion Starter #5
Post your timing map or send it to me. You should be easily making 500-550whp on pump gas. I was mid 500s on 91octane.(Assuming you fix your fuel pressure issues)
My car is in the paint shop until the end of next week, when I get it back I will load the map and show the timing
 

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93 Octane Fuel, sorry I will fix the OP, stock compression JE pistons and an OEM TT Headgasket so I think your on to something, Tuner said he could probably get 550 when I fix the Fuel Pressure issue.
I see posts all the time with people with similar Turbo setups making high 500's at 18-20psi? maybe thats what I was expecting

do you have to run E85 for 10-1 compression? I would run E85 if there was a station within 100 miles of me.
You "don't" have to run ethanal blended fuels with 10/1, but its a real good idea. I have never run 93 after the initial tune. The lowest ethanol percentage I have seen is 66%. I am in Indiana and literally have 5 stations within 10 miles that carry E85. My guess is you could run more timing than you currently are, which will bump up the power a bit. That's probably where they are leaving power on the table.

Steve
 

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I am in Indiana and literally have 5 stations within 10 miles that carry E85.

Steve
WOW. I had to buy a 30 gallon tank for my car. The closest service station that sells e85 is 38 miles away from me. I also take two 5 gallon containers I have if I think I'll be close to the stations. I'll fill them up and either put them in my car or the bigger tank I have. It's kind of a hassle, but it's all I can do.

As for the OP, I had a similar setup and was making 600 @ 24psi, but I can't remember what I was making at 19. This was with the same turbo but a stock block on 93 octane and methanol injection.
 

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Discussion Starter #8
WOW. I had to buy a 30 gallon tank for my car. The closest service station that sells e85 is 38 miles away from me. I also take two 5 gallon containers I have if I think I'll be close to the stations. I'll fill them up and either put them in my car or the bigger tank I have. It's kind of a hassle, but it's all I can do.

As for the OP, I had a similar setup and was making 600 @ 24psi, but I can't remember what I was making at 19. This was with the same turbo but a stock block on 93 octane and methanol injection.
The closest E85 station from me is 165 miles round trip, It's a nightmare if I wanted to run it. realistically I would be happy running 24psi but your gambling on 93 octane. My Dyno Chart is like a Supercharger Graph so strange.
 

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Boost Junkie
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The closest E85 station from me is 165 miles round trip, It's a nightmare if I wanted to run it. realistically I would be happy running 24psi but your gambling on 93 octane. My Dyno Chart is like a Supercharger Graph so strange.
Send us your graph with the torque curve in it. It looks like you have bad boost creep issues, which is why it looks like that. That could potentially mean you are making less boost in the lower RPMS and more in the higher RPMS. If that is the case then you're not hitting 19psi until nearly your redline, which isn't good. It makes the car feel laggy and it hurts low end torque as well as your peak HP should be around 6800-7200 with those cams. Peak torque will be around 5500 rpm. We also need to see it in RPM, not MPH.

Steve
 

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Discussion Starter #11
the numbers sound fairly spot on. i made the same with a 6765 with more boost (no valvetrain/head work, stock comp) on 93. how old is your fuel filter? alex had a similar issue with mine. tried to add more boost and fuel kept dropping. i tossed in a new filter....perfect fuel pressure.
My fuel filter was replaced back in 2012, my Tuner thinks it may be a wiring issue with it not getting enough voltage but it wouldn't hurt replacing the fuel filter again after 7 years



Send us your graph with the torque curve in it. It looks like you have bad boost creep issues, which is why it looks like that. That could potentially mean you are making less boost in the lower RPMS and more in the higher RPMS. If that is the case then you're not hitting 19psi until nearly your redline, which isn't good. It makes the car feel laggy and it hurts low end torque as well as your peak HP should be around 6800-7200 with those cams. Peak torque will be around 5500 rpm. We also need to see it in RPM, not MPH.

Steve
I believe my wastegate is on it's way out, I reused it from my last manifold and it was working okay with that setup but I changed the 15psi spring to a 10psi, my tuner says it's acting like an on/off switch so it may be sticking. for good measure I am going to get a new wastegate and rewire the fuel pump before I bring it back to him and see the difference.
 

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My fuel filter was replaced back in 2012, my Tuner thinks it may be a wiring issue with it not getting enough voltage but it wouldn't hurt replacing the fuel filter again after 7 years





I believe my wastegate is on it's way out, I reused it from my last manifold and it was working okay with that setup but I changed the 15psi spring to a 10psi, my tuner says it's acting like an on/off switch so it may be sticking. for good measure I am going to get a new wastegate and rewire the fuel pump before I bring it back to him and see the difference.
OK, just an FYI, that 6766 is so efficient it will creep with a single gate, at least that is my experience and many others. I had another gate added to my HKS manifold because of this. It was evident on 93, but even worse on E85. So you could continue to have boost creep even with a new gate. I am running dual Tial 46mms and have perfect boost control with the PROEFI. Low boost 12.6psi to redline and high boost it hits 38psi and tapers to 35psi just because the turbo is out of breath up there.

Steve
 

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Discussion Starter #13 (Edited)
OK, just an FYI, that 6766 is so efficient it will creep with a single gate, at least that is my experience and many others. I had another gate added to my HKS manifold because of this. It was evident on 93, but even worse on E85. So you could continue to have boost creep even with a new gate. I am running dual Tial 46mms and have perfect boost control with the PROEFI. Low boost 12.6psi to redline and high boost it hits 38psi and tapers to 35psi just because the turbo is out of breath up there.

Steve
I don't really have a lot of room on my manifold so that's why I was going with a 50mm, do you suggest a 60mm for a single gate?
Here's my Manifold before I wrapped it, the Wastegate piping seems like a decent design to me MVIMG_20171230_122944.jpg
 

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I don't really have a lot of room on my manifold so that's why I was going with a 50mm, do you suggest a 60mm for a single gate?
Here's my Manifold before I wrapped it, the Wastegate piping seems like a decent design to me View attachment 240709
You've got room off the front if you need it. You won't want to go too big on the wastegate as that makes it harder to control boost up top. A 60mm is a bad idea. I'd try a single (Tial 46mm would be my choice) and see how it goes. Then add a second one if needed. I'll send you a picture of mine for reference.

Steve
 

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I'm wondering what A/R turbine you're running. It looks like if you had more fuel and revved to 7800 you would hit 600 on low boost. Those cams and not having a divided TS turbo/manifold setup would make it laggy. Plenty of room to grow if that's what your goal is.
 

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Discussion Starter #16
I'm wondering what A/R turbine you're running. It looks like if you had more fuel and revved to 7800 you would hit 600 on low boost. Those cams and not having a divided TS turbo/manifold setup would make it laggy. Plenty of room to grow if that's what your goal is.
.81A/R T4 Precision 6766, I used to have a Turbonetics GT-K 850 and that was super laggy but would hit hard on my old setup, Ironically I wanted a better street turbo so chose the 67
 

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.81A/R T4 Precision 6766, I used to have a Turbonetics GT-K 850 and that was super laggy but would hit hard on my old setup, Ironically I wanted a better street turbo so chose the 67
Great street turbo. Same turbo I've had since 2011 and I am hard pressed to switch it out. Once you get your set up sorted out you'll love it.

Steve
 

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Discussion Starter #18
Great street turbo. Same turbo I've had since 2011 and I am hard pressed to switch it out. Once you get your set up sorted out you'll love it.

Steve
if I go with a dual wastegate setup will I have to get a 4 port mac valve to control the boost? I have a 3 port at the moment. just curious to your setup
 

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if I go with a dual wastegate setup will I have to get a 4 port mac valve to control the boost? I have a 3 port at the moment. just curious to your setup
Nope. You "T" the 2 waste gates together and use the same MAC valve you are using now.

Steve
 

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If it's possible I'd switch out those cams to have more power down low. Your dynamic compression on an 8.5:1 setup and pump gas will probably feel sluggish under 4500RPM. Unless you have a good tuner that can work around that*
 
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