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The Red Beast
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Discussion Starter #1
I got dyno put out 363rwhp and 395 torque with pump gas my supra BPU+ is auto with 3800stall CT boost 20psi with manual boost control and boost was falling after 5000rpm to 16psi. is that good or bad?
 

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With an auto trans, not bad numbers. 20psi on pump gas and the ECU will pull timing bigtime. Reset the ECU, throw 105 or more in the tank and try it again.
 

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I got dyno put out 363rwhp and 395 torque with pump gas my supra BPU+ is auto with 3800stall CT boost 20psi with manual boost control and boost was falling after 5000rpm to 16psi. is that good or bad?
I think I would ask that question in the "Dyno Tuning" forum.
The numbers sound reasonable but I don't know about the boost drop!
 

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Spring mod and race gas. 400+ here we come.

Later, Steve
 

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With only pump gas (which was likely resulting in pulled timing at 20psi) and drivetrain losses through a 3800 stall those are extremely good numbers.
 

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the #'s are not that bad for an auto....
 

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MKIV TT 6 Speed
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Good numbers given you have an auto and lose an additional 28-30% wheel horse power most high BPU guys on a 6speeds run around 420rwhp and -15% on your auto that’s 417rwhp. Your in good shape, but my only concern is you running on pump gas at that PSI you should be running at least 100-103 octane. I posted Phil’s post on this topic under.

This ratio is highly dependent on the ecu that you're running (i.e. the timing curve). With the oem ecu (and no timing piggybacks), a 'ballpark' starting point is to use a roughly 1:1 ratio above 14psi and 91 octane. Here is a VERY ROUGH guesstimate table to start with (octane=(r+m)/2*). Be sure to monitor/log your knock to confirm/verify:
Boost(PSI)__Octane ((R+M)/2)
----------__-----------------
14____________91
15____________92
16____________93
17____________94
18____________95
19____________96
20____________97
21____________98
22____________99
23____________100
24____________101
25____________102
26____________103
27____________104
28____________105
29____________106
30____________107
31____________108
32____________109
33____________110
34____________111
35____________112
36____________113
37____________114
38____________115
39____________116
40____________117
41____________118
42____________119
43____________120


FYI: Here's an example of how to calculate the 'net' octane if you mix fuels: 2 gallons of 93 octane pump gas with 6 gallons of 117 octane race fuel: ((2x93)+(6x117))/8 = 111 'net' octane.
Standard disclaimer: As always, ymmv.

* Do not calculate octane based on RON. Use only (R+M)/2, or preferrably MON.
 

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Most BPU 6-speeds make approximately 420rwhp with what would be 494 crank hp assuming a 15% drivetrain loss.

His 363rwhp auto makes approximately 454 crank hp assuming a 20% drivetrain loss. He is definitely low on power. Not to worry, it is becuase he is running pump gas. To make similar power (494 crank) as the 6-speed example, he would need to make 395rwhp. Right now he is 32rwhp short.

Not a problem with a little race gas and timing. My BPU Supra (stock intercooler) made 376rwhp on pump gas and 406rwhp on 100 octane with no other change except the gas.

The point is his numbers are very typical for an auto on pump gas at that boost level and his boost dropping off to 16psi is also very typical.

Later, Steve
 

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Steve, with a 3800 stall his drivetrain losses are probably closer to 25% --- putting crank power closer to 483hp. You're right though, a little bit more octane and this is an easy 11 second car with sticky tires.
 

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The Red Beast
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Discussion Starter #12
Copper gold supra

Well I thought I was low in power actually is not that bad. the guy that dyno my car said it run very rich at high rpm if I had map ecu and add some race gas I can be close to 400rwhp and my car has 155k mile on the stock mother.
 
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