E85 and boost, what compression ratio could I run?
#46
Using your calculator, my current setup with 84mm bore, 85mm stroke, 5.233" rods, 9:1 compression, 50* ABDC inlet valve timing, and 40 PSI boost, I get
7.96 dynamic compression ratio
29.62 effective boost compression ratio.
That is already significantly over your 18:1 sane numbers.
If I ran 12:1 and 35 PSI boost:
10.57:1 dynamic compression ratio
35.74:1 effective boost compression ratio.
7.96 dynamic compression ratio
29.62 effective boost compression ratio.
That is already significantly over your 18:1 sane numbers.
If I ran 12:1 and 35 PSI boost:
10.57:1 dynamic compression ratio
35.74:1 effective boost compression ratio.
At 20 psi you're at 18.77 dynamic with the same above info. Again just my target on race gas or E85 in a highly stressed environment. YMMV. In for results.
#47
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So if you consider 18:1 safe for track, and I have gotten away with 29.62:1 effective compression ratio, that is quite a difference. Do you think you could run more boost, or more compression on your setup?
#48
I know this thread is about high comp and e85 but there is also some good info about high(er) boost levels and e85. I want to add some timing to my map but a lot of timing tables that Ive found are all for lower boost numbers.
I hit 22psi at ~4700rpm and it tapers up to 25-26psi by 7250. E85, stock 9.5:1 pistons, stock rings, stock head.
My current WOT, full boost timing numbers are highlighted in the picture. Could I safely add 4-5 degrees in all the cells?
I hit 22psi at ~4700rpm and it tapers up to 25-26psi by 7250. E85, stock 9.5:1 pistons, stock rings, stock head.
My current WOT, full boost timing numbers are highlighted in the picture. Could I safely add 4-5 degrees in all the cells?
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jim_rocketmow
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10-29-2012 11:29 AM