Does running E85 affect turbo sizing?
Thread Starter
Joined: Nov 2005
Posts: 1,241
Likes: 1
From: Clearwater, FL
Does running E85 affect turbo sizing? Just curious. Someone told me the other day that they were told by a turbo supplier that a 76mm turbo wouldn't be big enough for them because they were running E85 instead of regular gasoline....but if they were running standard gasoline, it would have been the right size.
On an EFI car such as ours...there is no fuel being run through the turbo at all, so I don't see how this would affect anything. The turbo is just cramming the air into the motor, and then fueling is done after the fact. With E85, you just need to run it fatter and advance the timing to make up for the lower energy output (and then some)...right? Clearly this would require higher fuel pressures and/or larger injectors and fuel pump.
On an EFI car such as ours...there is no fuel being run through the turbo at all, so I don't see how this would affect anything. The turbo is just cramming the air into the motor, and then fueling is done after the fact. With E85, you just need to run it fatter and advance the timing to make up for the lower energy output (and then some)...right? Clearly this would require higher fuel pressures and/or larger injectors and fuel pump.
i dont know the answer...but have seen a few posts by drturbo on this subject E85 & turbo sizing.
The Turbo Project has Begun......
Posted By DrTurbo
One problem with your build. That is the E85 will choke the small GTK turbine wheel. Small is relative....as it would be fine for 700rwhp on a regular gas engine setup, but small as in it will probably only make 600-650 before it really chokes the turbine side. Going to E85, E95, Methanol fuels is a whole different world guys. The turbos have to be adapted to the application as well.
BW S388 turbo?
Posted By DrTurbo
[QUOTE=camaroandreas;8077908]363 cui, manley oversized valves,ported,Edelbrook intake,compcams valvetrain and XER287HR cam. I´m will have 9.2 compression and run on E85 ethanol. I have a own tuning shop here in sweden with a dynapack dyno, but this it the first V8 i ever build. So i´m greatful for all help. /Andreas On E85 you will need the larger turbine side for sure. The full S88 would be the ticket. It would spool awesome and make HUGE power on E85.
The Turbo Project has Begun......
Posted By DrTurbo
One problem with your build. That is the E85 will choke the small GTK turbine wheel. Small is relative....as it would be fine for 700rwhp on a regular gas engine setup, but small as in it will probably only make 600-650 before it really chokes the turbine side. Going to E85, E95, Methanol fuels is a whole different world guys. The turbos have to be adapted to the application as well.
BW S388 turbo?
Posted By DrTurbo
[QUOTE=camaroandreas;8077908]363 cui, manley oversized valves,ported,Edelbrook intake,compcams valvetrain and XER287HR cam. I´m will have 9.2 compression and run on E85 ethanol. I have a own tuning shop here in sweden with a dynapack dyno, but this it the first V8 i ever build. So i´m greatful for all help. /Andreas On E85 you will need the larger turbine side for sure. The full S88 would be the ticket. It would spool awesome and make HUGE power on E85.
Alcohol fuels burn cooler than gasoline, so it figures that something that is driven off hot exhaust gases (ie, a turbo) would have different requirements with different fuels. I have no idea why this would affect the compressor side, however.
TECH Enthusiast
Joined: Mar 2004
Posts: 604
Likes: 0
From: Loganville, GA
Ah CRAPPPPPPPPPPPPP. This throws a wrench into things... I would think you'd need a larger turbo with E85. You burn a lot more fuel when running E85 (approx 1.35 times more) and it burns hotter. I wouldn't see why not.
This never occurred to me.
This never occurred to me.
Thread Starter
Joined: Nov 2005
Posts: 1,241
Likes: 1
From: Clearwater, FL
I don't see how needing to burn more fuel for the same amount of air equates to needing to shove more air in?
I can understand the exhaust gas thing, but then that would mean you need a smaller exhaust side, not a larger one. You can't remedy less exhaust flow with a bigger cold side because then more than likely you're losing efficiency then.
Trending Topics
The amount of fuel burned is irrelevant. The compressor side is all about air intake. And E85 does NOT burn hotter. Ethanol and methanol burn MUCH cooler than gasoline. I'm guessing (no real world experience) that the cooler exhaust gases would screw with the backpressure ratio versus a same sized gasoline turbo.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Thread Starter
Joined: Nov 2005
Posts: 1,241
Likes: 1
From: Clearwater, FL
Okay, but that still means you would need a smaller exhaust side in order for the turbo to spool up better. If you were to go larger on the cold side, like I said above, you'd start having to worry about running the compressor (below) out of its better efficiency range, again, showing that a larger turbo would be worse, no?
TECH Enthusiast
Joined: Mar 2004
Posts: 604
Likes: 0
From: Loganville, GA
. But I'm going to wait until DrTurbo posts. 
Yes the volume of exhaust gases of a E85 car is more (your burning 30% more which passes through the turbine wheel). That is why Outlaw and the big drag cars that swap to alky based fuels have to go larger on the exhaust side.
Convert to straight E85 and you will notice it. We deal with alot of overseas customers that buy alot of turbos from us and they are all starting to use exclusively E85 in some countries. We have gotten alot of information and feedback on it. The general consensus is they love it. You can add lots of timing and the intake charge is cooler. Hard to argue with that.......great reciepe for making power.
TECH Enthusiast
Joined: Mar 2004
Posts: 604
Likes: 0
From: Loganville, GA
