E85 and back pressure
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E85 and back pressure I have been thinking of running e85 so that I can safely run high boost all the time. I have a station a few blocks from my house too.
I'm running a single t4 comp turbo and bp is at 1:2 ratio as it would be on a 370. If I made the switch would bp go up?
I know you need 30% more fuel and that's why I ask.
Alex
I'm running a single t4 comp turbo and bp is at 1:2 ratio as it would be on a 370. If I made the switch would bp go up?
I know you need 30% more fuel and that's why I ask.
Alex
Good question! I'm in for results. We pretty much run the same combo, just a few different things like heads cam and intake. Mine is lq9 364ci with Comp 80mm oil-less and the ct5 cover w/ t4 1.32ar.
How's the car been running any new videos? Any in car runs?
How's the car been running any new videos? Any in car runs?
Just double the HP you plan on making and that would be the CC of the injector you plan to run. For example 500hp (1000cc injectors) 600hp (1200cc). Back pressure.... really? I still cant understand that concept, a restriction on the exhaust/downpipe is good?
And adamantium, yes back pressure! Lol! Even if you have no restrictions on the exhaust/downpipe, wouldn't the back pressure be limited to how much the turbine could actually flow? Like, if the turbine was maxed out and couldn't flow anymore than it already is with a 4" down pipe that has no restrictions, going to a 5" downpipe with no restrictions is probably not gonna help much because the turbine itself is maxed out...regardless of the size of the downpipe. And he's worried about back pressure because of the possibility of lifting the heads. I have no experience with this, this is just my theory of how it works...lol! Any turbo/e85 gurus please chime in and correct me if i'm wrong.
He's saying that he's already at 1:2 back pressure running gas, so will his back pressure increase that much more if he runs e85 (30% more fuel)?
Last edited by deeloc1; Jun 14, 2012 at 01:14 PM.
I think OP is looking for a answer in regard to back pressure only when running e85. Injectors are easy to find. OP, correct me if i'm wrong...you're concerned with running e85 because of the added fuel (30% more) which in theory makes more power because of more fuel being introduced into the combustion chamber before ignition? You're wanting to know if e85 will cause more back pressure because of the added fuel over gasoline which requires less fuel to burn???
And adamantium, yes back pressure! Lol! Even if you have no restrictions on the exhaust/downpipe, wouldn't the back pressure be limited to how much the turbine could actually flow? Like, if the turbine was maxed out and couldn't flow anymore than it already is with a 4" down pipe that has no restrictions, going to a 5" downpipe with no restrictions is probably not gonna help much because the turbine itself is maxed out...regardless of the size of the downpipe. And he's worried about back pressure because of the possibility of lifting the heads. I have no experience with this, this is just my theory or how it works...lol! Any turbo/e85 gurus please chime in and correct me if i'm wrong.
He's saying that he's already at 1:2 back pressure running gas, so will his back pressure increase that much more if he runs e85 (30% more fuel)?
And adamantium, yes back pressure! Lol! Even if you have no restrictions on the exhaust/downpipe, wouldn't the back pressure be limited to how much the turbine could actually flow? Like, if the turbine was maxed out and couldn't flow anymore than it already is with a 4" down pipe that has no restrictions, going to a 5" downpipe with no restrictions is probably not gonna help much because the turbine itself is maxed out...regardless of the size of the downpipe. And he's worried about back pressure because of the possibility of lifting the heads. I have no experience with this, this is just my theory or how it works...lol! Any turbo/e85 gurus please chime in and correct me if i'm wrong.
He's saying that he's already at 1:2 back pressure running gas, so will his back pressure increase that much more if he runs e85 (30% more fuel)?
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That puts you a lot closer to me than expected...
I'm curious about both of your combos. I decided to sell my 8079 due to the turbine not doing what I wanted based on Sprayed 01's results. Comp spec'd mine for a 347 and I ended up finding a 6.0 20 minutes from the house.
I'm curious about both of your combos. I decided to sell my 8079 due to the turbine not doing what I wanted based on Sprayed 01's results. Comp spec'd mine for a 347 and I ended up finding a 6.0 20 minutes from the house.
That puts you a lot closer to me than expected...
I'm curious about both of your combos. I decided to sell my 8079 due to the turbine not doing what I wanted based on Sprayed 01's results. Comp spec'd mine for a 347 and I ended up finding a 6.0 20 minutes from the house.
I'm curious about both of your combos. I decided to sell my 8079 due to the turbine not doing what I wanted based on Sprayed 01's results. Comp spec'd mine for a 347 and I ended up finding a 6.0 20 minutes from the house.
I'm gonna stick with the Comp 8079 and see what i can get out of it. Mine has the ct5 cover on it with a t4 1.32ar housing. I'm gonna run a 4"dp. Sprayed01's back pressure of 1:2 is acceptable i think. If it doesn't turn out how i want, i'll sale it and get a 88 or 91mm. I'd love to own AWD S10 or Syclone with a turbo ls motor in it! I've actually been looking at a AWD Turbo Colorado for my next project since Izzy Performance's AWD Twin turbo Silverado has been kicking everybody's ***...lol! I think a twin turbo ls based AWD Colorado would be cool with a prerunner set-up too! kinda like this:http://www.dezertrangers.com/vb/gene...alk/107142.htmSorry for the hijack OP...back to the topic at hand! Has anyone out there measured backpressure with pump gas and meth, then measured it again when they switched to e85?
Last edited by deeloc1; Jun 14, 2012 at 02:52 PM.
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Turbos10, I hope you didn't base your decision on the first 80/79 I received. They sent me a new one and it made great power. Almost 800whp on 17psi through a locked auto and 9 inch.
Sprayed01, you are exactly why i'm sticking with the Comp 8079! You made 800rwhp @17psi with ported 241's and stock intake and tb...you could have easily made more with 317's, 243's or l92's with a ls6 or l78 intake! That's why i'm figuring my combo will make so great power @20psi with tfs 235's and fast lsxRT truck intake even with pump gas and meth! The additional 3psi+better heads+better intake should equal atleast 950rwhp...I THINK...LOL! We shall see...
E85 & BP - it's going to take E85 or race gas to get where we want to be. E85 is cheaper......
Sprayed01, I watched your first post with the billet compressor. Kurt Urban post was the final deciding factor. And the rebuilt 4788R only cost me a few $100 more than I can sell the 8079 for. Dee's 1.32 a/r housing would help some, but I want a few 8.5 slips to shut up a few people at work...Then turn it down and run PSCA Quick Street class (9.60 index racing) - If Fontana ever re-opens. I know the 88 will do what I want. Just up to me to get there with the rest of the setup and more than enough HP will make the suspension less critical.
I just don't think the 8079 turbine will support 900 on a 370 w/o a lot of BP. The only post I've seen with that much power was on a 331.
That's why I'm curious about your build's. -too see if I was wrong-
And I really like the turbo, just not quite what I wanted. I originally was looking for a 4508 when I found a used 8079 at a shop on the way home from work. I called CT to verify it w/ser # etc and they gave me a group buy deal on a new 8079 instead....wish I could afford to keep it and put it under the jimmy.
I like that colorado.
Sprayed01, I watched your first post with the billet compressor. Kurt Urban post was the final deciding factor. And the rebuilt 4788R only cost me a few $100 more than I can sell the 8079 for. Dee's 1.32 a/r housing would help some, but I want a few 8.5 slips to shut up a few people at work...Then turn it down and run PSCA Quick Street class (9.60 index racing) - If Fontana ever re-opens. I know the 88 will do what I want. Just up to me to get there with the rest of the setup and more than enough HP will make the suspension less critical.
I just don't think the 8079 turbine will support 900 on a 370 w/o a lot of BP. The only post I've seen with that much power was on a 331.
That's why I'm curious about your build's. -too see if I was wrong-
And I really like the turbo, just not quite what I wanted. I originally was looking for a 4508 when I found a used 8079 at a shop on the way home from work. I called CT to verify it w/ser # etc and they gave me a group buy deal on a new 8079 instead....wish I could afford to keep it and put it under the jimmy.
I like that colorado.
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From: Norn Iron
I have been thinking of running e85 so that I can safely run high boost all the time. I have a station a few blocks from my house too.
I'm running a single t4 comp turbo and bp is at 1:2 ratio as it would be on a 370. If I made the switch would bp go up?
I know you need 30% more fuel and that's why I ask.
Alex
I'm running a single t4 comp turbo and bp is at 1:2 ratio as it would be on a 370. If I made the switch would bp go up?
I know you need 30% more fuel and that's why I ask.
Alex
So as you'll likely make more power, and possibly more exhaust gas to go with it ? EGBP may well rise further.
And at 2:1 already, unless it has incredible spool that you need to retain, that's already a very high PR to be running.
You need more turbine flow as it is.
