what about running 50/50 meth water with pump gas?

not sure on that limit as it is dependent on how much you are spraying. have taken pump to 25psi+ on a 9.0:1 CR FC engine pinned with about 550cc spraying.

But then there are people like rice racing that runs just water at 34psi pump gas.

water is the best knock suppressor but it also doesn't generate power, high octane fuels burn and produce power. race high octane fuels being more ideal but you can supplement knock suppression with straight water also but you need lots of it and a bit more fine touch in the tuning process leaving less room for error.

to get that much boost safely you need to run 2-3 times as much WI as i mentioned and have a very stout ignition system.

Im so in between running the toulene and pump with 50/50 or just race gas ugh. I plan on 25 psi or more

no E85 option? while i realistically don't care for it with it's low energy content it can give pretty amazing results.

sometimes i promote pump gas a little too thoroughly but that is also because i sometimes drive my car thousands of miles one way. with the upcoming supercharger/turbocharged twin setup i know just pump and WI won't cut it.

They don't use rubber in cars anymore. All plastics.

Energy?
Don't have a problem with that either. I'm somewhere around 650 RWHP @ 30 PSI now. This is on E85 fuel that cost $3.50 a gallon.
Course I use 30% more, but am VERY happy with the results.

Seems E85 is then very hard to beat as long as it's easily available any where you go. 30% more usage implies ~$4.50 ($3.5 x 1.3) per gal when comparing to petro.

But if one wants to stay petro, why not just go to your nearby airport and get 100LL av gas? Local price is ~ $5.50 per gal. And would the caloric density be greater than the gas/toulene mix?

All we get here in CA @ the pump is 91. Going rate is ~ $4.30 per gal.
With Toulene @ ~ $15 per gal, a 5:1 ratio comes out to $6.08 per gal.
And all I get is roughly 97 (?) octane.

PS- is that an S4, S5, or REW under the hood??

S5 with a T72
Actually once you convert to E85, you can make a gas map and just fill up with gas if you want. Easy as changing your map.
Anyway...this is about tolene.........sorry I got off topic

E85 is out of the question. we only have one pump in town. My plan is to just drive the car once in a while and maybe track events (drag and road race). But im cautious of how long the fuel will last sitting in my tank. I dont wanna have to pump my fuel out of my car everytime im done driving it and it sits in the garage.

I have only one gas station in my town that sells E85.
Yeah...because of it's corosive propertys, you can't let it sit for long periods of time. It will pit your injectors and make them worthless.
I am 110% sold on E85 tho. You can give it as much boost as you want and it won't even hickup.

E85 is good but it's not for everyone.

No, but if you have it available, you should give it a shot.
No stock ECU will handle it, so if your car is stock, forget it.
I premix pretty heavily, so I think that saves my injectors from the hygroscopic coorsiveness.
I ran 25 PSI @ 13:1 AFR's and it didn't even give a hint of detonation. I wouldn't try that with gas.

Yea i agree bruce but im growing away from the car and it will be sitting and driven very rarely so i know e85 is out of the question. My drag car id like to run e85 in it tho.

when you say premium do you mean 93 octane?
according to post #3 in this thread:
http://bbs.clubplanet.com/useless-bl...race-fuel.html
i calculate a 20% mix toluene + 80% 93 octane = 96.5.
i.e.: .20(114)+.80(93)

why not xylene instead w/its higher octane? cheaper too.:
http://www.acehardwaresuperstore.com...ners/5847.html

Why you growing away from it? Im on the opposite end, now that im going single im completely in love again haha

Karack, i know that when prepping Toulene people mix it with ATF due to it being more corrosive and less lubricating than gasoline.

Do you think i can mix it with 2-cycle oil instead of ATF as i am about to start premixing and just would get out of the way everytime i fill up?

welll like you stated the atf is a lubricant added to the toulene so its not so corrosive so thats what 2 stroke oil is designed to do. I dont see there being any problem. Im sure two stoke is better than atf as you dont see people mixing atf in their garden equipment.

i would try 2 stroke over ATF anyday. ATF may help prevent carbon buildup better but it also really isn't much of a lubricant in a combustion environment.

I've always had an interest in seeing what Toluene can do to raise the limitations of the engine. I'm currently running 93 on a BW S366 and AquaMist HFS-3 with windshield washer fluid. I had a very conservative tune by Enzo, who told me that 21psi was the safest tune to make considerable power using pump gas. I'm only making approximately 450rwhp with this setup. What I would like to do is add 30% Toluene to the equation and see what it can do for me. Any ideas on what max psi I should tune to using that mix(93+AI+30% CH3)?

this is my rule of thumb for rotaries, 18psi is the threshold for minimum knock level with 91 octane pump gas in the US. every 2AKI(pump gas numbers) octane points gives you approximately 4 psi of knock suppression. with a 30% mix of toluene it would add about 3 octane points bumping you up about 6psi of knock suppression moving the raw pump gas(no AI added into the equation yet) to about 24psi of safety. add in the AI and you gain about 4psi of safety per 500cc's injected with a maximum of 49/51 alcohol/water mix(less alcohol and more water actually adds more knock suppression) which realistically gives you a roof of 28psi even with a conservative AI injector size.

some people have pushed 21psi(some pumps do list 93 octane with AKI figures, most western states max at 91 octane) on just pump gas before without any issue, just for reference but that is hardly safe IMO.

please note that the 100 octane figure i gave is based on RON(research octane numbers, what race gas uses mainly). pump gas in the US uses a calculation based off of AKI figures and is actually about 97 octane according to RON calculations. 20% toluene adds about 2.5RON octane points so 30% would add about 3 points.

the highest race fuel i can seem to find is leaded VP113 which is 113AKI(pump gas figure, RON+MON/2) which would allow 62PSI of knock suppression according to my calculations without the addition of AI in a rotary engine.

[url]http://en.wikipedia.org/wiki/Octane_rating[/url

for safety reasons i generally only tune 15% less than the knock threshhold of the rated fuel. for 91AKI that is 16psi max, as ambient temps and internal combustion temps rise knock suppression goes down.

compression level also is a consideration, these figures are based off of a 9.0:1 turbocharged rotary engine. higher compression engines will drop knock suppression figures by about 20% per .4 compression added.

this is just an observation and estimate through my personal research and testing with these engines, not to be used as concrete figures but what i believe to be close to accurate. ambient temps, intercooler efficiency and turbine sizing as well as tuning obviously play a big part in how easily an engine will detonate even at lower levels.

1988. Turbos were banned afterwards (soon to return in 2014) and Honda started to supply Mclaren with V10 engines for 89 and 90. 1991 was a V12.

Karack, i'm very interested in how you came up with 62psi as a knock threshold in our engines with 113 RON fuel. And does that boost pressure take into effect intake porting, or is that on stock ports?


The 80's F1 cars were limited in RON to 102, hence the mixture with heptane and iso-octane. Their main reason for using Toluene was not only the octane and knock suppressing qualities it gave (even at higher intake/fuel temperatures, helping BSFC) but also the density of it, making for less frequent re-fueling.

Also interesting was the fact that even given the same RON of the 3 mixtures posted by Arghx, the fuel mixture with the highest concentration of Toluene resulted in higher possible ignition advance and thus knock tolerance. Octane is not everything, so I'm learning!
I have some Xylene I picked up a while back to try, just need to put an engine together first to test it :( I figured with Xylene due to the slightly higher Octane rating, you could get away with less and suffer less from the poor vaporization characteristics, since the two chemicals are quite similar.

Attachment 698280

I wonder why F1 didn't consider Xylene over Toluene?

my question is what max boost can the FC turbo block and FD block withstand for more than a few seconds? 62 psi @ 8500 rpm we're looking @ around 1,500 bhp. doubt these engines will stay together for more than a second at them levels.