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2.4 Supercharger pulley size boost calculation

fubar569

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#81
Idk man, hot is hot. Who tunes your car again? lol
Curt.

Ask speedy what temps he was comfortable with. If I recall he was hitting 160's and that was about his reasonable limit. Since he had OST at first I'm sure if they saw anything wrong with it Mike would've said something.
 


Speedy!

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#82
Not sure if later models are different from what my 2016 was, but I'd have about 2 deg of timing pulled by the time the MAT was in the 150s. I never saw above about 165° F so that 2 deg pull in timing was the max I saw. I never saw a boost reduction from MAT that I ever noticed.

My tune was setup with a gradual increase in MAT HOT timing reduction up to about 1.7 aircharge, then flat from then on. It's based on a reference IAT max value for max pull of timing. It's been a while but I think I left that reference value stock.
 


fubar569

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#83
Not sure if later models are different from what my 2016 was, but I'd have about 2 deg of timing pulled by the time the MAT was in the 150s. I never saw above about 165° F so that 2 deg pull in timing was the max I saw. I never saw a boost reduction from MAT that I ever noticed.

My tune was setup with a gradual increase in MAT HOT timing reduction up to about 1.7 aircharge, then flat from then on. It's based on a reference IAT max value for max pull of timing. It's been a while but I think I left that reference value stock.
Mine would very evidently dump boost as well at exactly 145 this year until things were adjusted back to where they were before the chiller install. Maybe it was an oversight but I'd go from 19ish to 11ish and only when IAT2 eclipsed 145. Whether that is an 18+ thing or an oops thing I'll probably never know. But one revision later I'm clipping 9.8's pretty solid in good air. No KR, no other timing pulled, IDC/FP look good, good fuel in the tank, plugs look good. I'm happy.
 


TheGasMan

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#84
Does anyone have this kind data for the TRX? I have been searching high and low on the interwebs for information/data like this for a couple years now. I live in the south where it’s hot&humid most of the year, and I’m trying to figure out if spinning the 2.39L SC faster with 93oct would be noticeable over stock when heat soaked from DD in 100 degree weather. Would a Gen.6 Whipple, ported heads, higher flowing exhaust, 5in intake and possibly a more efficient heat exchanger and plumbing, if that’s even a thing, do anything to reduce timing being pulled in said conditions?
 


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Unholy707

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Thread Starter #85
Does anyone have this kind data for the TRX? I have been searching high and low on the interwebs for information/data like this for a couple years now. I live in the south where it’s hot&humid most of the year, and I’m trying to figure out if spinning the 2.39L SC faster with 93oct would be noticeable over stock when heat soaked from DD in 100 degree weather. Would a Gen.6 Whipple, ported heads, higher flowing exhaust, 5in intake and possibly a more efficient heat exchanger and plumbing, if that’s even a thing, do anything to reduce timing being pulled in said conditions?
It’s the same chart. An aftermarket supercharger runs cooler period and you can make the same power with less boost
 


TheGasMan

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#86
It’s the same chart. An aftermarket supercharger runs cooler period and you can make the same power with less boost
The tuner/performance-shop that I’ve been working with lately is convinced that IHI/factory SC runs hotter than factory, or at least goes from an overheated SC state back down to normal operation temps faster. Is this not true?
 




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