how much HP capable with 91 octane w/ std meth injection ?

[TurboZ28408]

curious how far you guys have gotten on 91 with a single fogger methanol injection kit.

Currently on an MPT70 Turbo at 649 WHP 667 tq..

considering going to a BW S475 but it'd be pointless if i can only pull out another 50 WHP out of it and lose out on a TON of low and midrange that I currently have.

[MIGHTYMOUSE]

its more a function of CID

people claim 800 1000+ around here on pump gas alone, but back in the day when i was trying to be cool like that i melted pistons and got over it.

nowadays i dont let it go over 17psi without better fuel, 17 still plenty for a 9 second pass so i don't see it as a problem.

[JETmn]

The bigger the turbo, the cooler the intake charge so you will get more power out of the same boost with the bigger turbo. Have you checked intake temps at all with your current turbo? What boost are you running?

[MIGHTYMOUSE]

not going to oversize my turbo for the sake of intake temps, have meth and ice water'd intercooler that do a nice job of holding the iat's in the 70's

i run 14 on pump only 17 on pump and meth and anything higher which has been to 23 goes with 104 unleaded or whatever the house brand happens to be of leaded.

[JETmn]

Since when are we talking about your setup? I was replying to the OP.

[MIGHTYMOUSE]

urite, i read it the wrong way

yea i dunno what system its on but i'd say he's got some room to go on the dyno, but i wouldnt personally go much more on the dragstrip

[Shearer]

Originally Posted by JETmn

The bigger the turbo, the cooler the intake charge so you will get more power out of the same boost with the bigger turbo. Have you checked intake temps at all with your current turbo? What boost are you running?

Making more power with a bigger turbo is not a direct result of cooler intake temps. You're moving more air for the same manifold pressure.

The power capability of a pump/meth set-up is directly proportional to how much meth you're spraying and how willing you are to turn the boost up.

[JETmn]

Originally Posted by Shearer

Making more power with a bigger turbo is not a direct result of cooler intake temps. You're moving more air for the same manifold pressure.

Are you talking on the intake or exhaust manifold? I am a NABR member too, so I know who you are I am just looking to learn some more.

['Trust']

Originally Posted by MIGHTYMOUSE

not going to oversize my turbo for the sake of intake temps, have meth and ice water'd intercooler that do a nice job of holding the iat's in the 70's

i run 14 on pump only 17 on pump and meth and anything higher which has been to 23 goes with 104 unleaded or whatever the house brand happens to be of leaded.

Which octane on 14/17psi?

[MIGHTYMOUSE]

93 is what's around here

[2001-WS6]

MM right though that 17psi is the reasonable max for 91-94 octane on meth. You need to balance boost and timing for your combo though and not treat this as a hard and safe rule.

I've pushed it to 19psi on 94 octane and meth but it was on a relatively cool day running ice. Either way it should be plenty for mid to high 9s with the right combo.

Rick

[JETmn]

So why can't the LS engines run higher boost on pump and meth? The import guys run 30+ psi on it. I know the pistons are bigger, so that will mean it takes the flame front longer to travel and I am sure the heads aren't as efficient as the imports. I am going to be building an LS based car soon and I am trying to learn as much as I can to get a good setup. What kind of timing are you guys running?

[MIGHTYMOUSE]

boost 'pressure' is a measure of resistance to flow, not horsepower, look at horsepower

for me timing is not fixed, depending on the boost it could be from 40 to 12*

[Pro Stock John]

I just wrote up a TT'd GTO for GMHTP and basically the combo is a 403ci, 8.6:1 and made 680rwhp on a Dynomite dyno with 91 pump gas. No meth.