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4x4le · 04-11-2009, 12:47 AM

If you were going to ever consider running this setup on gas (even race gas) I would say horrible idea. I think allot of the guys in this thread might not have much experience with actually tuning an e85 vehicle however, and I do and I have spoke with many other e85 tuners as well and we all agree on 1 thing, its very odd to us how detenation is NEVER present even after we go past the threshold where timing no longer benefits the hp/tq.

That alone has really made me want to do a high compression turbo vehicle. The reason you dont see it much is because its not worth it (on a gas motor, maybe e85 as well but time will tell when someone does it) because it just makes for a tuning nightmare. Everyone that has tried the high compression turbo setups has ended up with the realization that more boost would have been easier and safer and smarter.

The info on a turbo can only make X amount of horse power on any engine is very untrue. Take a holset turbo for example. It spools fast on the cummings and makes great tq but not a lot of hp due to the fast spool and the low rpms of the engine. Now put that turbo on a rotary motor. It will not make much tq and will make decent power. Rotarys that make good hp #s are usually ported like crazy and high revving with a good flowing turbo. They almost always however make less power than a piston engine with the same turbo (due to their exreamly low compression) which brings me to my next point: put that same holset turbo on a ka and see that it makes good tq (but still less than the cummings) but better hp than the rotary.

So in my eyes, just reading compressor maps alone means nothing because all engines are not =
Compression ratios and displacement to start with are one of the major things that cause a turbo to react differently on each engine, followed by cams. Some cams will just plain not allow enough air to enter the engine causing higher manifold pressure while the hp output does not actually increase, while some very extream cams can actually bring small turbos out of their effency range on no more boost than stock wastegate springs.

Anyways, I like youre idea if your willing to run nothing but e85 in the beast. You will have very good tq numbers due to the turbo being able to spool like never before (did you know that e85 creates more exhaust gasses than gas does too?) with high compression and e85. Also when the turbo is spooling up untill a little past the peak tq rpm its smart to run it a little richer and this will allow for even more timing which will spool the turbo even faster and create gobs of tq.

You cant just be unsmart with the timing, if your not making more power dont throw more timing at it, but your not really going to have to worry about detenation as much as a gas tuner is. You will probably be supprised at how much timing your actually going to be able to throw at the engine though! That part just isnt going to make sence to you, at first at least!

Go ahead and do it, then show the haters the results.

04-11-2009, 12:47 AM	#8
4x4le Zilvia FREAK! Join Date: Nov 2008 Location: Manchester, Tn Posts: 1,253 Trader Rating: (1)	If you were going to ever consider running this setup on gas (even race gas) I would say horrible idea. I think allot of the guys in this thread might not have much experience with actually tuning an e85 vehicle however, and I do and I have spoke with many other e85 tuners as well and we all agree on 1 thing, its very odd to us how detenation is NEVER present even after we go past the threshold where timing no longer benefits the hp/tq. That alone has really made me want to do a high compression turbo vehicle. The reason you dont see it much is because its not worth it (on a gas motor, maybe e85 as well but time will tell when someone does it) because it just makes for a tuning nightmare. Everyone that has tried the high compression turbo setups has ended up with the realization that more boost would have been easier and safer and smarter. The info on a turbo can only make X amount of horse power on any engine is very untrue. Take a holset turbo for example. It spools fast on the cummings and makes great tq but not a lot of hp due to the fast spool and the low rpms of the engine. Now put that turbo on a rotary motor. It will not make much tq and will make decent power. Rotarys that make good hp #s are usually ported like crazy and high revving with a good flowing turbo. They almost always however make less power than a piston engine with the same turbo (due to their exreamly low compression) which brings me to my next point: put that same holset turbo on a ka and see that it makes good tq (but still less than the cummings) but better hp than the rotary. So in my eyes, just reading compressor maps alone means nothing because all engines are not = Compression ratios and displacement to start with are one of the major things that cause a turbo to react differently on each engine, followed by cams. Some cams will just plain not allow enough air to enter the engine causing higher manifold pressure while the hp output does not actually increase, while some very extream cams can actually bring small turbos out of their effency range on no more boost than stock wastegate springs. Anyways, I like youre idea if your willing to run nothing but e85 in the beast. You will have very good tq numbers due to the turbo being able to spool like never before (did you know that e85 creates more exhaust gasses than gas does too?) with high compression and e85. Also when the turbo is spooling up untill a little past the peak tq rpm its smart to run it a little richer and this will allow for even more timing which will spool the turbo even faster and create gobs of tq. You cant just be unsmart with the timing, if your not making more power dont throw more timing at it, but your not really going to have to worry about detenation as much as a gas tuner is. You will probably be supprised at how much timing your actually going to be able to throw at the engine though! That part just isnt going to make sence to you, at first at least! Go ahead and do it, then show the haters the results.