questions on timing, fuel, and premix
#1
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First of all, Timing... other than stock timing i have heard of a lot of different theories on people running retarded, slightly advanced and also advancing like 30* and claiming better power among other things. I have a stock port s4 engine with exhaust, intake, just installed msd 6a and coils, and a bunch of other little things.
#1. Without dyno tuning, what is the easiest way to road test for best performance while only adjusting timing. I have messed with it alot by adjusting 5* up or down and doing a run through 3rd gear to see how it feels. When retarded 5-15* it seems slugish while free reving in neutral but seems like a linear power band on the road not realy being able to notice any power gain or loss, just a different feel with poor throttle response. Advancing is different, I can advance my timing 5* and it feels almost the same as advancing 30*. (these are numbers on a normal timing light, Im not sure how they are figured on a rotary but i think they are half of the actual reading) When advanced the throttle response is excellent, very noticeable in neutral free revving. on the road though it feels like a good pull to about 5k then feels like the power kinda evens off without increasing but still pulls slightly to 7500. so the question is, what is the best way to butt dyno your timing?
#2. Old problem with my car but still puzzles me, i put solid mounts on engine and tranny and noticed normal increased vibration that wasnt unbareable. after one real hard run to 100, it then vibrated very badly from 6-7k. now ive noticed that the vibration changes a lot with my timing, almost like the vibration is detonation except its n/a and detonation is just unlikely.
#3. Ive searched about this for a long time and cant find an answer, does 2 cycle oil affect octane....?
#4. Can you advance timing enough to completely burn higher octane fuel?
#5. what is the easiest way to see if your injectors are leaking, sticking, working properly?
mostly stupid questions but I cant find the answers from anyone, what are your oppinions?
#1. Without dyno tuning, what is the easiest way to road test for best performance while only adjusting timing. I have messed with it alot by adjusting 5* up or down and doing a run through 3rd gear to see how it feels. When retarded 5-15* it seems slugish while free reving in neutral but seems like a linear power band on the road not realy being able to notice any power gain or loss, just a different feel with poor throttle response. Advancing is different, I can advance my timing 5* and it feels almost the same as advancing 30*. (these are numbers on a normal timing light, Im not sure how they are figured on a rotary but i think they are half of the actual reading) When advanced the throttle response is excellent, very noticeable in neutral free revving. on the road though it feels like a good pull to about 5k then feels like the power kinda evens off without increasing but still pulls slightly to 7500. so the question is, what is the best way to butt dyno your timing?
#2. Old problem with my car but still puzzles me, i put solid mounts on engine and tranny and noticed normal increased vibration that wasnt unbareable. after one real hard run to 100, it then vibrated very badly from 6-7k. now ive noticed that the vibration changes a lot with my timing, almost like the vibration is detonation except its n/a and detonation is just unlikely.
#3. Ive searched about this for a long time and cant find an answer, does 2 cycle oil affect octane....?
#4. Can you advance timing enough to completely burn higher octane fuel?
#5. what is the easiest way to see if your injectors are leaking, sticking, working properly?
mostly stupid questions but I cant find the answers from anyone, what are your oppinions?
#3
Originally Posted by Mint87RX7
#1. Without dyno tuning, what is the easiest way to road test for best performance while only adjusting timing. I have messed with it alot by adjusting 5* up or down and doing a run through 3rd gear to see how it feels. When retarded 5-15* it seems slugish while free reving in neutral but seems like a linear power band on the road not realy being able to notice any power gain or loss, just a different feel with poor throttle response. Advancing is different, I can advance my timing 5* and it feels almost the same as advancing 30*. (these are numbers on a normal timing light, Im not sure how they are figured on a rotary but i think they are half of the actual reading) When advanced the throttle response is excellent, very noticeable in neutral free revving. on the road though it feels like a good pull to about 5k then feels like the power kinda evens off without increasing but still pulls slightly to 7500. so the question is, what is the best way to butt dyno your timing?
#2. Old problem with my car but still puzzles me, i put solid mounts on engine and tranny and noticed normal increased vibration that wasnt unbareable. after one real hard run to 100, it then vibrated very badly from 6-7k. now ive noticed that the vibration changes a lot with my timing, almost like the vibration is detonation except its n/a and detonation is just unlikely.
#3. Ive searched about this for a long time and cant find an answer, does 2 cycle oil affect octane....?
#4. Can you advance timing enough to completely burn higher octane fuel?
#5. what is the easiest way to see if your injectors are leaking, sticking, working properly?
#4
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Originally Posted by Mint87RX7
everyones asleep but BUMP for those awake cuz these problems are killing me
Second, only #2 is truly a problem.
The other 4 are not considered problems.
-Ted
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