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You think it would be too high for E85 even? RB Racing's boost compression calculator tells me with 4 psi I would end up with 13.25:1 at Detroit's altitude.

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I think the compression is a tad high. If you went with a set of composite .060 head gaskets you could. Also you could probably get away w/ 6 psi of boost and why people runner inner-coolers anymore to me is crazy. Meth injection is the way to go. Much cheaper and easier to set-up. Not sure what turbo you'd need. I'm sure there's a math formula to figure that out.

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To me, smart people run intercoolers instead of meth/water/whatever mixture you want because they don't want to rely on a generally cheap system to be the only reason their engine survives.

Obviously with the carb guys they get some nice cooling through the introduction of the fuel earlier in the airstream than on the EFI setups. But regardless, if the engine relies on not detonating solely because of the supplemental injection system, that's asking for disaster.

Sure, there are lots of other systems that you also rely on for the engine to run, like a fuel pump, but that's kind of unavoidable. Not to mention if your fuel pump dies in a bad way the car should go so lean so quick that it likely won't even combust anymore. Not like when a meth pump locks or corrodes or leaks, and the car runs at a 13.5:1 AFR instead of the 11.0:1 it used to with full supply of meth.

It's an opinion deal, no doubt. I just thought I'd share some thoughts.

I would personally think that if the timing were kept in check, that E85 should allow you to run boost without an intercooler. It would be for sure good if you had an nice intercooler setup. Just don't expect to run X PSI at 30* timing. Back the timing off to 20* and move up from there if it takes it. Or leave it alone and up the boost, it'll make more power than the timing will.

Your cam profile should make it harder to detonate with a turbo combination as well. But that depends highly on the hot side components of your turbo system.

Also, I wouldn't stray any smaller than a GT4202.

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If you cut fuel supply, you can detonate real hard, real quick. I don't really see the meth injection being any more dangerous than anything else, so long as you keep the meth tank full and you hook up a switch to manually test the meth pump before you use it. One other thing to keep in mind is meth cools better than an intercooler and you don't get that pressure drop you do. Also it's a lot less work to plumb in a meth injection system.

E85 + 10.5CR + boost should be very do able. The guys working on the newer stuff have CR that high from the factory and some of them are running aftermarket combos with a LOT of boost. You will have to pay careful attention to timing and a/f ratios. Also your "big n/a cam" will likely be detrimental to building boost. If you've got a lot of overlap or a narrow LSA, you may want to change to a more boost friendly cam instead of blowing your boost right out the exhaust.

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Judging by your board name I would assume you've experienced "boost cut" on a Turbo Mopar when you surpass the MAP. It doesn't cut ignition when it does that, it cuts fuel, completely. If there is no fuel present, there will be no combustion period.

Now, if a pump starts to taper off in supply ability, or you have a voltage drop issue, surely you will run into a problem. But you can't avoid that until you go race an electric car

You CAN avoid having a $50 pump die out in the middle of a run and not catching it in time. Ask James Reeves what happened when he got to a point that his motor consumed about as much alky as it was fuel.

And in regards to the pressure drop issue, if you're concerned with that then you have too small of a turbo on your car. Unless you're on the verge of maxxing your compressor way beyond it's map, it's not going to care pushing enough CFM (oh boy, not that acronym again!) for another 1-2 PSI.

And while certainly not an apples comparison as far as price range, a well done A/W system will keep intake temps sub 80* in 95* ambient at 25 psi on a 510 CID motor throug the traps at 199.

Now, if you just run the car on E85 anyways then now worries either way! And turn it up and enjoy the newfound power.

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Could I get a 10.5:1 340 with iron heads and a big N/A race came to run reliably with a turbo set at 3-4 lbs (or what ever would be safe) of boost and use E85 for fuel? If so, what would be the right turbo? Would I need an after-cooler or inner-cooler? I don't personally know any one to ask. No one I know runs forced induction. Thanks

P.S. Here is a link to the [url=http://www.compcams.com/Cam_Specs


/CamDetails.aspx?csid=671&sb=2]cam specs[/url]

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Judging by your board name I would assume you've experienced "boost cut" on a Turbo Mopar when you surpass the MAP. It doesn't cut ignition when it does that, it cuts fuel, completely. If there is no fuel present, there will be no combustion period.

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And in regards to the pressure drop issue, if you're concerned with that then you have too small of a turbo on your car. Unless you're on the verge of maxxing your compressor way beyond it's map, it's not going to care pushing enough CFM (oh boy, not that acronym again!) for another 1-2 PSI.

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Well sometimes you have to work with what you have. Especially if you have a supercharger and tweaking boost levels is not so easy.

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That means you need to step up to turbos!

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Judging by your board name I would assume you've experienced "boost cut" on a Turbo Mopar when you surpass the MAP. It doesn't cut ignition when it does that, it cuts fuel, completely. If there is no fuel present, there will be no combustion period.

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Big difference between efi and carb fuel cut. With efi you can cut the fuel off instantly and completely. With a carb when a fuel pump dies, the float bowl for the secondaries may run out of fuel before the primaries. That could be bad news. When you start to boost there are any number of ways of doing damage, and that damage can happen in a second or two.

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And in regards to the pressure drop issue, if you're concerned with that then you have too small of a turbo on your car. Unless you're on the verge of maxxing your compressor way beyond it's map, it's not going to care pushing enough CFM (oh boy, not that acronym again!) for another 1-2 PSI.

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Well sometimes you have to work with what you have. Especially if you have a supercharger and tweaking boost levels is not so easy.

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Well sometimes you have to work with what you have. Especially if you have a supercharger and tweaking boost levels is not so easy.

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That means you need to step up to turbos!

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some of us arne't good welders..