E85 turbo engine, which pistons 8.8:1 or 10.6?
#1
E85 turbo engine, which pistons 8.8:1 or 10.6?
So as mentined above, I´m going to install forged stuff in my block. Rods will be ebaystuff and arp headbolts and acl race bearings. I´m running with E85 fuel and I´m thinking what compression ratio to choose? 10.6:1 ratio might help with spool and performance below boost area.
Thoughts, experience...
Thoughts, experience...
Last edited by jim_rocketmow; 09-27-2012 at 01:33 PM.
#9
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I vote 13:1 why not.
Pump gas. If you have an EMS with a flex fuel sensor and timing/fuel trim OR alternate maps, you can pull this off. It will really complicate things though and you might even still knock at 0psi.
#12
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NO. I thought you were going E85 100% of the time????
Sure with water/meth AND a fuel flex sensor AND dual maps you could run pump and boost with high compression pistons.
But
Do you actually know how to tune? You had better know how to tune or have a deep pockets and a great tuner to keep your engine from blowing up. Also, a WI system with failsafes will cost you around $400.
I run water/meth and pump and if I could run E85 all the time, I would throw the stupid WI system in the trash.
#16
I don't know miata's like I know DSMs and Evo's, but in the "other" world we've been going bigger and bigger with compression ratios on pump and E85. Its not uncommon to see 10:1 or greater running over 25psi on 92oct. Now there's a huge apple to walnuts comparison here and Evo's have great heads, but why doesn't tuning for MBT with high compression and med to high boost work on the miata's as well?
#17
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I don't know miata's like I know DSMs and Evo's, but in the "other" world we've been going bigger and bigger with compression ratios on pump and E85. Its not uncommon to see 10:1 or greater running over 25psi on 92oct. Now there's a huge apple to walnuts comparison here and Evo's have great heads, but why doesn't tuning for MBT with high compression and med to high boost work on the miata's as well?
Tuning for MBT with high compression works like **** because you are fagora
#18
I don't know miata's like I know DSMs and Evo's, but in the "other" world we've been going bigger and bigger with compression ratios on pump and E85. Its not uncommon to see 10:1 or greater running over 25psi on 92oct. Now there's a huge apple to walnuts comparison here and Evo's have great heads, but why doesn't tuning for MBT with high compression and med to high boost work on the miata's as well?
Now that more EMS' are offering advanced knock detection, we can finally make some progress in the right direction....Like the rest of the world has over 5 years ago.