pyro719

iTrader: (5)

If e85 is readily available in your area go that route. Its 105 octane fuel for $3.00 a gallon it cant be beat.

93camaro_zzz

iTrader: (13)

My motor is 9.06:1 CR and i dynoed 607rwhp on just california 91 octane. 9 psi APS twins kit

ryanleiker

iTrader: (2)

Bringing this thread back up because I got my build done...

Now that I've experienced the power level on the street of my current setup, I'm considering that pump gas may give me plenty of usable power versus e85.

Anyone have any more input on the topic?
I've got 80lb injectors, would these be too large to convert back to pump gas?

chiaj144

iTrader: (4)

I'm running 120lb injectors on a stock 5.3 and it runs great.

stevieturbo

80lb injectors arent large by any means. And will at least allow you to make some decent power with pump gas.

Orr89rocz

iTrader: (13)

As mentioned, gt45 is gonna be the choke point imo not the 93 oct gas.

Key is intercooling and tune. Watch iat and timing

I've done 1009 sae on 93 with cool iats. Now in summer iats hit 170, i was pulling 8 deg to be safer. Ran well

ryanleiker

iTrader: (2)

At this point I'm running about 11psi and I probably won't go much higher as anything higher and the power is basically unusable on the street.

With this much pull, I don't think I'll upgrade the turbo until I potentially go to twins, unless it would cut my spool time significantly.

69-chvl

iTrader: (11)

My LQ9 seems to not even be breaking a sweat at 12psi, IAT's with a cheapy ebay a/a ic are at about 120* at the end of a quarter mile pull on a summer day. Dont even need meth/water injection at this level. Stupid power even at this level.

Once you get over ~14psi the games changes fast though - watch that tune!

Forcefed86

iTrader: (4)

Nice build, ever go out to the wichita dragstrip?

80's are fine and usually the pump gas injector of choice in turbo builds. I'd throw some meth inj on run pump gas. "denmah" just made 700+whp on pump gas with 80lb injectors.

https://ls1tech.com/forums/forced-in...-76billet.html

ryanleiker

iTrader: (2)

I haven't been out to the strip in years as I've been in and out of the hot rod game the last few years. Once I get a little bit more in the build I'll take the car out to the strip.

chasgiv3

iTrader: (1)

I run 160lb injectors. 8.7:1 CR on my setup. I'm not sure what my limits are on pump gas but I race on 100 octane and pull around 1000RWHP on the dyno. On the street I run pump gas but I've never really pushed full boost there. Maybe 22 PSI out of my max 26. I guess adding a little octane for me is cheap insurance versus an $8,000.00 engine rebuild plus new turbos when the shrapnel flows through the turbo vanes spinning at 120,000 rpm. I would probably feel comfortable with pump gas with a good quality and tuned meth kit.

stevieturbo

With that CR I can see no reason at all for you not being able to push to 1k and beyond on pump fuel unless your chargecooling is poor.

Other than a dropped valve or similar which will see catastrophic damage, an engine failure through tuning that would in turn damage the turbos would be incredibly rare.

yenkomike

iTrader: (2)

my lq4 is a stock engine with a comp 206/212 cam ,ls9 gaskets and good springs . I run 93 pump only at 10# boost and 11* timing it runs 10.50s at 130 mph. in my all steel nova. I have done some changes and I think I can run 10 flat to 9.90s on 12 lbs boost and pump gas . I will find out before to long.

ryanleiker

iTrader: (2)

Is there any data that says I will gain or drop horsepower going from the e85 to 93 under the same boost numbers with identical setups?

Obviously the fuel consumption will be dramatically less, but I wonder what this will look like in actual crank output numbers....

Forcefed86

iTrader: (4)

Bit of a loaded question. It depends if you can run peak torque timing with pump gas or not. E85’s higher octane has a slower more controlled burn. Pump gas burns faster and hotter by comparison. Added heat isn’t a bad thing as long as you’re not seeing any detonation. 11lbs isn’t much. Assuming you don’t need to run “sub-optimal” timing, you may not see any losses in performance.

I’d run one of the cheaper $200ish Alky Inj. kits on 50/50 for a little extra cushion. I don’t see any reason to deal with the headaches of E85 to run 11lbs of boost.

Orr89rocz

iTrader: (13)

E85 may see slightly cooler intake charges and just might make more power that way. My friends civic claims 90 hp on e85, from a race gas, no change in tune. Not sure i buy it but thats what they claim. My other friend did e85 from c16 but also changed intake manifold. It runs as fast with 2 psi less boost but i think its the intake to blame there

Main thing is e85 should allow few deg timing and make more hp that way than 93 gas. No other change in tune wont allow you to reap its full benefit. Just may see slightly lower intake temp goin into chamber

Forcefed86

iTrader: (4)

Peak Torque Timing (some call it “max break torque” or MBT timing) is the initial ignition point that provides the most complete burn of the fuel in the cylinder at a given AFR. This will extract the most power from AFR being burned.

If you can run PTT on a lower octane, adding higher octane fuel and advancing the timing won’t make more power. It will actually make less. You would be lighting off the mixture sooner (BTDC). Meaning your lighting off the charge while the piston is still on its way up the cylinder. For the best power you want the least amount of octane and ignition lead as possible to hit PTT while maintaining enough octane to prevent detonation.

In many cases with turbo engines PTT cannot be attained on pump fuel. So adding higher octane and advancing the timing will make additional power.

ToxicWS6

not thread jacking (or trying not to lol) but same thing here, have a lq4 .020 over, LS9 gaskets, ARP studs, EPP blower cam, MP76mm .72Ar cold/1.0AR hot, 6 speed, 9in 3.70s, have a 11.9psi WG spring in it and i plan on running on 93 oct, planning on 10-11 degress timing, once my tuning is done and its "safe" ill hook my meth kit up and run the 50/50 washer fluid just as a IAT temp safty thing, hoping to make 550rwhp not break past 600rwhp cause i dont wanna replace the engine again this summer lol

is the above seem accurate/any flaws in thoughts/plan?
is this basically what you went with op?

OP what was your final fuel, boost pressure, timing and WHP? if you know, assuming this was all on your cam lq4?

ryanleiker

iTrader: (2)

I have no idea what my current HP is.

My final engine assembly:
Stock 2002 LQ4 engine.
Tick Performance (Martin Smallwood) turbo cam
LS7 lifters
LS2 GM head gaskets
Pro Comp head studs
GT45 (69mm 1.05 A/R) turbo
VS Racing intercooler
11psi currently through a manual boost controller
I don't remember what my final timing is
I am running E85 currently
80lb Siemens Deka injectors

ToxicWS6

ok cool, ive been thinkin about going E85 but theres only one station in our area with it and they keep changing owners so my luck ill convert over and then they'll take the E85 away lol

as soon as i get my clutch situation taken care of my car will be on the road and seeing how this goes, was driving it around for 2 days but clutch was contaminated : \ engine ran damn good though lol