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Hey guys,

My gtt has around 250kw at the treads with an aftermarket turbo, pfc and all. It was tuned with Shell V Power 98.

I was wondering if i run V Power Racing 100 at the drags, would it help or hurt the power output? is the different fuel gonna mess up the tune, a/f ratio and etc? hence good or bad for engine/turbo?

Cheers guys

Edited by BaysideBlue
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not a ad idea at all. it will not improve your performance at all but will make your safety margin slightly bigger. will also not mess up your AFR's.

I agree, you will improve your protection from pinging but you may actually lose a couple of killerwatts due to to fuel being less volitile....(burns slower so you need to add more timing to compensate) but i doubt that you would notice as it would be more to do with air temp/relative altitude than 2 RON difference in fuel.

Andrew

Stick with your usual fuel and octane booster. You won't gain 7 points on anything but base unleaded, maybe 2-3 tops on 98 octane.

I recently ran some nulon pro strength through mine on the dyno and it had no effect on the mixtures and increased the detonation threshold significantly (enough that i could add 5 degrees of timing before any audible pinging).

Adding toluene effects your mixtures as you have to add so much of the shit to get a significant increase in the RON of your fuel. Were talking 5-6 litres per tank of fuel (thats near enough to 10% by volume) to get a couple of point increase.

Adding toluene effects your mixtures as you have to add so much of the shit to get a significant increase in the RON of your fuel. Were talking 5-6 litres per tank of fuel (thats near enough to 10% by volume) to get a couple of point increase.

and if you stuff up things can go pretty wrong. i was asking my mechanic about toluene and he said it is better to stay away from it cause a small mistake can have large consequences.

Depending on how far you want to go, toluene is the best option. It only aided F1 back in the 80's to achieve the high horsepower figures they had and ran.

Problem with the octane boosters is the higher the initial ron of the fuel the lesser increase you see from adding it.

mad082 can you explain your mechanics reasoning for not using/advising toluene?

V-Power will actually LEAN OUT your mixture, not richen it up.

Not by a lot, but mine went from 12.0 to about 12.2 on the Optimax Extreme.

When I put it in my car, I normally leave the AFR and just add some timing.

But I don't use it often.

thanks guys for the replys.

so using 100 octane fuel on 98 tuned engine will lean out the mixture which would increase safety margin but need to adjust timing. how exactly do i do that?

and also, is it worthwhile doing (pay the extra cost for v power racing + adjusting timing) for the so said slight increase of safety margin, without any real performance increase over the quater mile?

so using 100 octane fuel on 98 tuned engine will lean out the mixture which would increase safety margin but need to adjust timing. how exactly do i do that?

rule of thumb is if you are asking how to tune your car then dont do it yourself. Get a tuner and a dyno

Edited by Bl4cK32

higher-octane fuel will lean out the mixtures, except as the the octane level is the fuel's rating of resistance to detonation it will probably be safer for the motor.

However, using a higher octane fuel without a tune may not see any gains because the burn rate will be reduced and the motor will not be running optimally. Best bet, just run 98octane what your car was tuned with.

If you really must, an amateur way of adjusting ignition timing to get the most out of a higher octane fuel is done by moving the CAS anti-clockwise slightly, test driving and repeat until you reach an acceptable knock level i.e. 20-30. Or read up on paulr33 PFC guide.

Edited by BAMR33
higher-octane fuel will lean out the mixtures, except as the the octane level is the fuel's rating of resistance to detonation it will probably be safer for the motor.

However, using a higher octane fuel without a tune may not see any gains because the burn rate will be reduced and the motor will not be running optimally. Best bet, just run 98octane what your car was tuned with.

ok sounds like theres no point using v power racing without a tune or at least adjust timing then.

If you really must, an amateur way of adjusting ignition timing to get the most out of a higher octane fuel is done by moving the CAS anti-clockwise slightly, test driving and repeat until you reach an acceptable knock level i.e. 20-30. Or read up on paulr33 PFC guide.

thanks i will try that.

if thats how your planning on doing it. Dont bother. Unless you got a timing light and your checking base timing as you go, its not worth it mate. Will probably cause more problems then its worth.

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