Official IS-F Drag Time/Dyno Time/Performance Thread
04-27-09, 03:51 PM
#91
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04-27-09, 03:53 PM
#92
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04-27-09, 04:40 PM
#93
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It does say minimum 91, but I have personal experience with CA 91. It behaves like 89, not 91. Adding some race gas will likely make a difference, but only some. There is no "diminishing return." If the fuel has adequate octane for the engine and load, more octane will not improve things (I've actually seen very high octane fuel dyno worse because the energy in it was less than a lower octane fuel). All octane tells you is how much compression and how much load the fuel will tolerate before it auto-ignites and causes either pre-ignition (not desperately bad) or detonation (death to the engine in seconds - AMHIK.)
Octane is load dependent, so in theory you could run regular in the IS-F and it would tolerate it as long as you don't put a big load on the engine. Of course the likelihood an F owner ISN'T going to step on the gas hard is pretty small, so we need at least 91 octane to ensure the engine management isn't working overtime to try and minimize the bad effects of pinging or detonation.
Again, if its California 91, I'd add about 20% 100 octane to ensure there is enough detonation resistance to prevent the ECM from backing off the ignition timing and losing power. This is readily apparent at the track where you're at WOT for the whole quarter mile.
Octane is load dependent, so in theory you could run regular in the IS-F and it would tolerate it as long as you don't put a big load on the engine. Of course the likelihood an F owner ISN'T going to step on the gas hard is pretty small, so we need at least 91 octane to ensure the engine management isn't working overtime to try and minimize the bad effects of pinging or detonation.
Again, if its California 91, I'd add about 20% 100 octane to ensure there is enough detonation resistance to prevent the ECM from backing off the ignition timing and losing power. This is readily apparent at the track where you're at WOT for the whole quarter mile.
04-27-09, 05:23 PM
#94
Lexus Test Driver
It does say minimum 91, but I have personal experience with CA 91. It behaves like 89, not 91. Adding some race gas will likely make a difference, but only some. There is no "diminishing return." If the fuel has adequate octane for the engine and load, more octane will not improve things (I've actually seen very high octane fuel dyno worse because the energy in it was less than a lower octane fuel).
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Isn't that the definition of diminishing returns
Going up in octane as you stated past the level of peak performance can actually diminish performance hence the law of diminishing returns!The tendency for a continuing application of effort or skill toward a particular project or goal to decline in effectiveness after a certain level of result has been achieved.
Last edited by 8speed; 04-27-09 at 05:31 PM.
04-27-09, 05:50 PM
#95
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Isn't that the definition of diminishing returns Going up in octane as you stated past the level of peak performance can actually diminish performance hence the law of diminishing returns!
The tendency for a continuing application of effort or skill toward a particular project or goal to decline in effectiveness after a certain level of result has been achieved.
Going up in octane as you stated past the level of peak performance can actually diminish performance hence the law of diminishing returns!The tendency for a continuing application of effort or skill toward a particular project or goal to decline in effectiveness after a certain level of result has been achieved.
Producing power is completely independent of octane, and not all very high octane fuels will reduce output, only certain blends in specific applications.
05-04-09, 08:34 PM
#96
I'm in the Viper club here in Kansas City and they do a free dyno day every year for paid members. Took the Viper and the ISF since I plan on ordering the Joe Z intake and exhaust. (Want to hear the exhaust in person before ordering). Any way during the day there were about 20 Vipers so I was definately the runt but did get 3 pulls in. All stock with half tank of 91 and half tank of 93.
Thats my Blue and white on the left
Thats my Blue and white on the left
05-10-09, 08:39 AM
#99
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The STD correction factor is an inflated correction factor. How much rwhp did your car make SAE with smoothing set to 5? I think the adopted norm (especially here on CL) is SAE and smoothing to 5.
Peter
Peter
05-10-09, 04:08 PM
#100
Yeah thats what Joe Z mentioned on a different board. This week I'll see if they saved the run and can reprint it using SAE, cause i'm curious how it did with other stock ISF's. All the cars were dyno'd using the same factors all day, as the Viper Club gives out trophies for the biggest number and also the Viper runt of the day
I found my Dyno sheet from the same place 3 years ago and then they used CF: SAE and Smoothing 3. Back then I did 447rwhp and 491rwt. This year using CF: STD the same car did 463rwhp and 503rwt so that explains the difference. (bout 3.5%)
Here's a video a guy made of the dyno day. Video doesnt show the winning supercharged GTS, putting down 1050rwhp and 1050rwt.
http://videos.streetfire.net/video/K...Day_680314.htm
I found my Dyno sheet from the same place 3 years ago and then they used CF: SAE and Smoothing 3. Back then I did 447rwhp and 491rwt. This year using CF: STD the same car did 463rwhp and 503rwt so that explains the difference. (bout 3.5%) Here's a video a guy made of the dyno day. Video doesnt show the winning supercharged GTS, putting down 1050rwhp and 1050rwt.
http://videos.streetfire.net/video/K...Day_680314.htm
05-12-09, 08:15 PM
#103
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Hey Peter,
If I had to take a guess based on what I see; I would say between run 2 & 3 there was an approx 11 minute cool down period...
I would also guess the car was turned off for most of that time period.
The 352 rwhp run, would seem to be the most accurate...
Sungkyo -> Thanks for getting your Dyno runs re-graphed
Joe Z
If I had to take a guess based on what I see; I would say between run 2 & 3 there was an approx 11 minute cool down period...
I would also guess the car was turned off for most of that time period.
The 352 rwhp run, would seem to be the most accurate...
Sungkyo -> Thanks for getting your Dyno runs re-graphed
Joe Z
05-12-09, 10:49 PM
#105
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Baseline stock Dynorun 356rwhp and 332ft lbs tq on Dyno Dynamics and corrected too
Now I really wanna see what I can hit on a DynoJet? Do I have a factory freak?
Going to dyno again soon on this same dyno since I have my intake and exhaust already. Just breaking it in before dynoing again.
Now I really wanna see what I can hit on a DynoJet? Do I have a factory freak? Going to dyno again soon on this same dyno since I have my intake and exhaust already. Just breaking it in before dynoing again.
Last edited by ISF-88; 05-12-09 at 10:56 PM.