A decent fm and efficient turbo, so you should be able to run 20-22 psi at 18-20 degrees of timing on 93 octane alone, with no alky. Those injectors are marginal for 93 only (you have to flow a lot of fuel to make up for the low octane). You can push it a good bit more than you did on the dyno, but remember that on the track it will lean out if you run the dyno tune. Just watch the knock detector.
How Much HP & Boost on Pump Gas?
- Thread starter MNwe4
- Start date
A decent fm and efficient turbo, so you should be able to run 20-22 psi at 18-20 degrees of timing on 93 octane alone, with no alky. Those injectors are marginal for 93 only (you have to flow a lot of fuel to make up for the low octane). You can push it a good bit more than you did on the dyno, but remember that on the track it will lean out if you run the dyno tune. Just watch the knock detector.
GNBRETT
Pelennor Fields
- Joined
- Feb 8, 2004
Im sure there will be some nice billet wheels out over the winter. How much boost u gonna run with the 109 on pump/alky?
Is Bobby done with S2 yet?
odnt know about pump alky. Im sure i could go up to 28-30 with reduced timing. When i run it hard ill have Q16 and alky and timing:biggrin: . Not done with the S2 yet. Dont want it till i can use it anyway:biggrin:
Are you still running the stock fuel lines from tank to fuel rail??
Not for long. I am currently though:biggrin:
Back to the orginal question/thread topic:
There's waaaay to many variables to answer how much power anyone makes with 93 and alky.
With dual alky nozzles, you can replace more of the overall fueling with alky (i.e.-more alky vs. pump gas) and thus make more power if tuned correctly. That's just one large variable to take into consideration. Then you have to take in to consideration what equpiment is being usedheads, cam, temperature control, weight, internals, intercooler, turbo, etc, etc...and most importantly, the tune.
Use the search function. This topic has been brought up about 40 triple billion times.
There's waaaay to many variables to answer how much power anyone makes with 93 and alky.
With dual alky nozzles, you can replace more of the overall fueling with alky (i.e.-more alky vs. pump gas) and thus make more power if tuned correctly. That's just one large variable to take into consideration. Then you have to take in to consideration what equpiment is being usedheads, cam, temperature control, weight, internals, intercooler, turbo, etc, etc...and most importantly, the tune.
Use the search function. This topic has been brought up about 40 triple billion times.
Alright I'm just gonna lay out what I know for sure about my car since I refuse to believe that I can't make over 18lbs and 471hp with 93 octane and 2 alky nozzles without getting knock. Knock does show up past 18lbs as I heard it back in December when I was back in Stl. The car has not made the move with me to MN yet. Here's the list and I'd really like to learn from you guys and hear your opinions.
Injectors: 65lb
Fuel Pump: May be stock?, but does have MSD voltage booster
Turbo: 68gtq
Heads: GN1 with ported plenum and intake to match, plenum spacer also
Intercooler: ATR front mount
Headers: ATR copies
Cam: 218 roller
Exhaust: 3" ATR
Downpipe: 3" ATR with external wastegate
Alky Inj: SMC with 2 nozzles
RJC Engine Girdle
When I put my foot in it the fuel pressure is in the mid 40 psi range from what I remember. Even running it hard, I've never seen the engine temp past 175*. Last dyno results had the timing at 18* WOT and A/F in upper 10:1 range. Any more thoughts?
Injectors: 65lb
Fuel Pump: May be stock?, but does have MSD voltage booster
Turbo: 68gtq
Heads: GN1 with ported plenum and intake to match, plenum spacer also
Intercooler: ATR front mount
Headers: ATR copies
Cam: 218 roller
Exhaust: 3" ATR
Downpipe: 3" ATR with external wastegate
Alky Inj: SMC with 2 nozzles
RJC Engine Girdle
When I put my foot in it the fuel pressure is in the mid 40 psi range from what I remember. Even running it hard, I've never seen the engine temp past 175*. Last dyno results had the timing at 18* WOT and A/F in upper 10:1 range. Any more thoughts?
Holy crap dude you need a fuel pump.
What is your fuel pressure at idle with the vacuum line off of the fuel pressure regulator.
Whatever that pressure is, you add the amount of boost you are running and that is what your fuel pressure should be at WOT. (40psi of fuel pressure + 18psi of boost= 58psi of fuel pressure at wide open throttle)
Also sounds like you need some type of a scan tool.
What is your fuel pressure at idle with the vacuum line off of the fuel pressure regulator.
Whatever that pressure is, you add the amount of boost you are running and that is what your fuel pressure should be at WOT. (40psi of fuel pressure + 18psi of boost= 58psi of fuel pressure at wide open throttle)
Also sounds like you need some type of a scan tool.
I know my fuel pressure at idle is down around 30 psi, but that is with the vaccum line on I guess. I'm in minnesota now, but the car is still in missouri for the winter, so I can't go check it or bring it up here. That's another reason this whole tuning process is so frustrating because I can't be there so I miss a lot of stuff. I'm just trying to learn as much as I can. I can't remember far enough back if we had a new fuel pump put in, but I know we have good wiring and the MSD voltage booster. I'll make a call to find out if the pump was upgraded as well. Could a slight exhaust leak cause knock like in this case?
Probably not on the exhaust leak.
You have to check fuel pressure with the line off, because if the line is on the fuel pressure gets pulled down with vacuum, then when you go into boost it goes up.
I really think you need to take it to someone that knows what they are doing with these cars.
You have to check fuel pressure with the line off, because if the line is on the fuel pressure gets pulled down with vacuum, then when you go into boost it goes up.
I really think you need to take it to someone that knows what they are doing with these cars.
Ok, I see what you're saying about the fuel pressure. Oh, and I do have an upgraded fuel pump, just don't know what kind as it doesn't specify on the invoice. But you're probably right about tuning, looks like I'll be looking for a good performance shop in MN this spring if things don't turn around. Anybody have any strong recommendations? Thanks for all the help.
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