pdasterly

iTrader: (4)

forged 347 5.7 9.1cr, d1sc(3.4 pulley).
80lb injectors, nasty rails, aeromotive afr, dual walbro in-tank
91 octane california gas

30th t/a

iTrader: (51)

On my old twin turbo setup I ran 15psi with 8.7:1 cr on straight 93 octane. I forget what the timing was.....I think 13*?

pdasterly

iTrader: (4)

rwhp/rwtq?

1998TA__1991RS

iTrader: (23)

i ran 15lbs in my forged (9.2:1) 347 with 93 pump and 10* of timing, never dynoed but it ran 6.24@115 at 3600lbs

fatmat80

I put down 600+rwhp on california 91..Dont remember how much timing, no meth..with a 3.85(8#) pulley. No issues...Tuned by Nick at Newtech.

Johnv

you could probably run #15 boost, but you wouldn't get much timing in it at the top end and would need to run reasonably aggresive IAT spark retard at higher intake temps.

Don't know why people are scared of meth,
A well setup system is reliable and and can have failsafes built in, and will allow you to safely run a decent amount of boost/timing without detonation.

'Trust'

iTrader: (24)

It really depends on what the car likes, then combustion chamber, timing, efficiency etc. I wouldn't want to make over 600rwhp on 91 pump if you were to put a number on it.

rotary1307cc

iTrader: (5)

big factor will be if it is intercooled or not

Pro Stock John

iTrader: (34)

600-650rwhp I think would be safe, I think 700rwhp would be a push.

I was 8:1, 347 cid, turbo, and went 10.00@139 mph on 16 psi without really trying to run a big number.... I'd say that was 650 rwhp @ 3400 raceweight.

pdasterly

iTrader: (4)

intercooled, yes

Josh@PremierAutosports

iTrader: (11)

My turbo 404 trapped 156mph on 14psi with 93. Your head, cam, IAT, and tune and so much to do with how much power you can make on pump gas. I would 110% suggets running meth with crappy 91.

LS1RedZ

iTrader: (19)

I made 780rwhp on straight 93 with 9.1:1 compression (FMIC). Not sure if that is pushing it or not??

ReApEr75

iTrader: (4)

That is awsome.

blue00ZZleeper

iTrader: (5)

I was making 580ish rwhp/550ish rwtq on 9psi without meth...I added for safety/my current build

Julio

Your knock sensor will tell you first..

Then the ringlands

Old Geezer

iTrader: (3)

old dog, you!

Julio

Easy way is to spray meth on top of a good tune.. let it drop some afr.. and then add in a bunch of timing.. locate the IAT after the meth nozzle.. and if temp goes up.. cause there is no meth spraying.. yank timing like crazy.

This is a win win scenario.. you drop afr from 11.5:1 to 10.5:1.. and increase timing from lets say 12-14 degree's to 18-20. You pickup power and if the spray doesnt work.. your back to where you started at with the crappy low timing.

But I know this is off subject.. trying to make power on low octane fuel and keep doing it is not for everyone. Typically to build a motor to accomplish this costs 4x the cost of any meth kit. If you have the dough.. buy the heads, big cam, build the motor, etc.. once oil starts creeping into the combustion chamber cause your driving it around.. that motor will not be as friendly with the low octane fuel. Let alone the CA 90 octane with up to 10% ethanol

Big difference when dealing with pistons with crud on top of them vs a brand new motor making 3 second dyno pulls with a fan blowing in front of it.

Chevy406

iTrader: (12)

The ability to make good power on pumpgas is what separates the stock 5.3 builds from the built, forged, aftermarket head engines. Yes you can make good numbers with the stock parts, but you have to push the combination harder which in turn requires more detonation resistance (octane). Like Julio said...

Firechikn

iTrader: (15)

I ran 15lb on the street and 93. Should of been in the 850 or range to the wheels. 14* timing.

30th t/a

iTrader: (51)

600/603...unlocked 4L80E...2nd gear pull, stock 317s, LS6 cam