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If I'm experiencing some detonation at WOT (but none at part throttle), should I:
1. Retard the base timing 2 degrees, and leave my FP where it is (static 52-54), OR
2. Leave my timing at 16 degrees, and increase the static FP by 2 psi at a time.
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6 psi JRSC GSR: 3" intake -> 217 hp/155 ft-lbs.
New: Endyn stepper, GSS342
Some basic setup info: 9psi (stepper), JR FMU, stock injectors, MAP mod, JR BTC (if needed, but usually set to 0)
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6 psi JRSC GSR: 3" intake -> 217 hp/155 ft-lbs.
New: Endyn stepper, GSS342
Add more fuel first, if that doesn't work start retarding the timing in small increments.
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Innovator of the JRSC electronic boost controller
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the thing that I'm worried about is when I add more fuel by increasing static FP, I ended up getting 1 yellow led on my a/f gauge. But that was in 4th gear at WOT around 6K rpm. I guess I'll return my timing to 16 degrees and up my FP 2 psi at a time.
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6 psi JRSC GSR: 3" intake -> 217 hp/155 ft-lbs.
New: Endyn stepper, GSS342
Ok. Timing is back to 16 degrees. I ramped up my static FP from 52 psi to 56 psi and while I was at that, I drilled a .040 mm relief hole in the FPR (slightly smaller than the 1/16" or .0625 mm hole that other people are using, but larger than TOO's recommended 1/32" or .031 mm).
Idle FP dropped immediately after the relief hole mod down to 42 psi (from 48 psi). I haven't checked the static FP yet, although I should do that soon. I did notice that the car is a little harder to start, but I took Max Psi GSR's advice and I let the fuel pump prime first. I may make the hole a little larger if the static FP is still roughly the same.
Car feels much more responsive at the top-end (from the higher FP) and the low-end is back (from raising my timing back to 16 from 14). I still get some really light pinging in 4th and 5th gear at WOT. I just purchased 5 gallons of Trick 101 octane gas. I'll add a gallon to an empty tank of gas and top it off and see if that takes away the problem.
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6 psi JRSC GSR: 3" intake -> 217 hp/155 ft-lbs.
New: Endyn stepper, GSS342
[This message has been edited by 217gsr (edited January 29, 2002).]
Sure richening your mixture will help quench things a little, but your mileage will drop and your plugs will expire much sooner. Adding only one gallon of race gas to a full tank of 91 won't raise the octane enough to run stock timing. If you want to run 16 degrees, you'll need at least 95 octane to be safe. All cars seem to vary a little on this one though. Your cylinders get extremely hot at WOT with stock timing and 6psi of boost. You need a fuel that can resist all the heat of compression. If your car isn't a daily driver, I'd suggest running race gas most of the time. That's what I do. If you are a daily driver, get a boost retard ignition. If you run pure race gas, it will allow you to lean things out a little (try 47-52psi). If you're serious about optimizing the performance of your car have your A/F checked on a dyno. Optimally, JR recommends 12.5. With 100 octane I have my fuel pressure set at 48psi and my timing at 16 degrees with no boost retard. I get over 30mpg on the highway with this setup. Give it a shot.
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2001 GS-R, JSRC 6psi (215whp & 157trq), Kami Headers, AEM CAI, AEM Cam Gears, Tanabe G-Power Exhaust, H&R Sport Springs, Tokico 5-Way Adjustables, MufflerTech Custom Test Pipe, 17" 5-Zigen GT8 Wheels, Neuspeed Short Shifter, Neuspeed Front Strut Tower Brace, B&M FP Gauge, JR MAP Controller, Zip's O2 Simulator, Skunk2 Rear Sway Bar, Skunk2 Rear Strut Tower Brace
[This message has been edited by bobbrown (edited January 29, 2002).]
When I was at 6 psi, my setup was 16 degrees, 91 octane pump gas, no boost retard on my BTC, MAP mod, GSS317, static FP of 50-52 psi, and I NEVER got any detonation. On a recent trip from the Bay Area back to San Diego, I got 32 mpg (well, more like 31.75 mpg). http://www.hostboard.com/ubb/smile.gif
I am now at 9 psi (stepper pulley). I have a new GSS342 fuel pump and my static FP is up. I can completely eliminate the detonation if I use ~2 clicks on the BTC, but I'd rather not have to do that because boosted performance suffers.
Unfortunately, running 95 octane gas is not an option for me here in CA. The best that I can do is add 1-2 gallons of 101 octane / tank OR add fuel additives like 104 Octane (which I'd rather not do). I have considered using Toluene, which is cheaper and has a higher RON octane (114), but I will try this method first and see if it works out. Using more than 1-2 gallons / tank is not cost effective anyways.
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6 psi JRSC GSR: 3" intake -> 217 hp/155 ft-lbs.
New: Endyn stepper, GSS342
If all you have to do is use the BTC at .2 degrees retard per lb with 16 degree base timing to solve your detonation issues and be safe, then I'd say you should consider yourself lucky, set your BTC at .2 and move on. I'd be surprised if you're really losing much power with that small amount of retard, or whether it's enough difference to be worth the potential problems from the pinging you're experiencing.
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Hmm... does retarding the timing with boost really degrade the performance that much?
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Black '00 GS-R
JRSC @ 6psi
Comptech Header / Comptech Exhaust
GC Coilovers/Tokico Illuminas
Comptech Front STB / Spoon Sports Rear STB
ITR Rear Swaybar w/ BSQ Mounting Kit
SSR GT1s / 205/45/16 Yokohama Paradas
Never mind... my question was answered while I was posting. =)
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Black '00 GS-R
JRSC @ 6psi
Comptech Header / Comptech Exhaust
GC Coilovers/Tokico Illuminas
Comptech Front STB / Spoon Sports Rear STB
ITR Rear Swaybar w/ BSQ Mounting Kit
SSR GT1s / 205/45/16 Yokohama Paradas
CKim:
at .2 degrees of retard / lb of boost, I am getting 2.2 degrees of retard at full boost (which is around 11 psi at higher rpms). This difference is definately noticeable. Night and day, if you ask me. But the tradeoff to be safe is priceless. I'm just looking for ways to run at "100%."
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6 psi JRSC GSR: 3" intake -> 217 hp/155 ft-lbs.
New: Endyn stepper, GSS342