Thread: E85 on hi comp RR DE?

What gains are predictable with E85 on 12-13:1 CR RR DE? With typical mods like ssac header, exhaust, intake and ECU and drop-in cams like S3R or Poncams. Port and polish for head, intake and tb is also considered. Im asking if its even worth opening up a block or rather keep it under 11.5:1 CR and regular fuel. Thanks

No ideas?

I dont know much about E85, but going from 10:1 to 12:1CR should see around 5% gain in power.

A typical 10:1 bolt on DE makes around 160whp so you'd probably be looking around 170whp with the CR bump. I dont know whether any further advantage from E85 can be taken with this setup, i suspect it would be minimal.

Really to make the most of the extra CR and to get significant gains, i'd look at bigger cams if you are opening the motor up, as you're never going to make good HP numbers on S3's or poncams.

Short of that, its the "you mght as well go VE" route.

Sure, i know about VE rout... ive did plenty of VE swaps, it will be even cheaper, but trying new things is interesting for me. This is focused for midrange mailny and torque.

I think i saw even 10whp gain from E85 on VE, thats why im asking.
I do even know that bigger cams will work much better, but this is budget build and Catcams, springs and cam gears cost a lot. And cams can be replaced in future if evetyhing else is done...

Hey, Jagy.

I wouldn't use more than 30% of E85 in a tank. I mean, use it as an octane booster, not as unique fuel (it's 85% ethanol, you have to be careful with the oxygen sensor. Ethanol can have as much as 35% of O2).

Apart from that, it's corrosive and its efficiency is around 20% less than regular fuel.

Main advantadge is you can advance timing without having detonation so you will have more power than using single 98RON.

Take into account the actual % of work of your injectors, since (from all the test I've seen here) you will increase it around 10% with just 25% of E85 in a tank. You can always use bigger injectors anyway

Lot of logs and tests to do (and precautions to take) but results are worth the try.

A lot of EVOs and STIs here use it with good results (between 20 and 30% of a tank, tho).

Keep us posted!

^ some of your information is incorrect.

its not corrosive, theres been numerious tests and it doesnt effect anything.

e85 is equivalent to 115 oct.

so if depending on your compression, your knock limitations etc. its no different then running c16 threw your motor.

the only difference is you will need to run 30% more on average. also it has the cooling characteristics of methanol.

i tried it, not sure how i felt about it, i feel i need more time to say wiether i liked it or didnt, at the end of the day its my opinion only.

alot of high comp honda guys run it, alot of sti and evo guys do also, and there is a handfull of sr20 guys who run it.

stratton.

Some of your information is incorrect.

Yes, it's corrosive - True.

It doesn't affect anything - Probably true too.

Maybe not enough to destroy rubbers and plastic (specially in relatively modern engines), but it is -not a major concern imho-.

Anyway, I haven't remarked that as the reason why I wouldn't use it without mixing (but the O2 sensor).

I am 12.3:1 CR in a DE but haven't tried... for now.

A lot of people run only E85, i wont plan mixing it with regular fuel. This wont be good for AFR.
I have 370cc injs, thats not a problem. Ive read about E85, builds, what do i need, etc... im asking here about my build idea, what people with experiences think about it.