How much boost?
#1
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How much boost?
Using the info in the DIY thread I figured out that for 220 hp at 80 psi of fuel at 80% duty cycle I need 293cc min injectors . My question is how do you figure out how much boost you need in corolation to injector size and fuel pressure?
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#3
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So how do I figure it? I would like to run 10 psi.
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#4
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220BHP x 12:1 AFR x .00916 = 21.18 CFM
BHP x AFR x BSFC/60 = REQ CFM
(CFM x CONSTANT X (460 + AIT) / VE X RPM/2 X CID) - 14.7 = PSI
21.18 x 639.6 x 550 / 3500 x 97.7 = 21.78psia - 14.7 = 7psi
like i said, it gets you close, but there are many other factors involved.
BHP x AFR x BSFC/60 = REQ CFM
(CFM x CONSTANT X (460 + AIT) / VE X RPM/2 X CID) - 14.7 = PSI
21.18 x 639.6 x 550 / 3500 x 97.7 = 21.78psia - 14.7 = 7psi
like i said, it gets you close, but there are many other factors involved.
#5
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lol, is there a thread in here where I can learn what all the abreviations mean?
I should just buy a wideband, shouldnt I?
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I should just buy a wideband, shouldnt I?
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#7
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Ok, so just so I know, when I get a wideband and I get my fuel pressure correct with my 1.8's at 7psi. Which it should be already. When I swap to larger injectors like 330's this should cause me to go rich right? and then i could just turn up the boost to correct the afr?
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#8
In theory yes. What FP are you gonna run an dwhat rate on your FPR the rate might overrichen you on tip in and cause you to lose power. with a rrfpr and a healthy pump capable of 80 psi 220whp should be doable on a mid to small size t28 before you hit 10psi if you have the right cooling and timming in place. If not you can blow to 15 psi and you still won't make the power you want just a bunch of silent knock.
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#16
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Jesus, just buy a megasquirt. I don't know why anyone would dick with FPRs, RRFPRs, lean/rich tip-in, trying to idle injectors, new fuel pumps, and then trying to figure out how to correct the timing in all that mess.
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Any donations will be gladly accepted.
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#20
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Sell your Bell AFPR. That alone should get you halfway to MS. Then you can run 440 injectors and make all the power you need without putzing around with AFM adjustments and FPR tweaks.
You can probably make the 330s work on the stock ECU if you are so inclined. However it's a bit like kissing your sister- you can do it, but why on earth would you want to?
You can probably make the 330s work on the stock ECU if you are so inclined. However it's a bit like kissing your sister- you can do it, but why on earth would you want to?