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While we are on the discussion of race fuels, I was looking through the Base maps for the TT Supra AEM EMS the other day for a friend, and came across a couple that were produced by www.horsepowefreaks.com and one is for 130 octane!! I have never even heard of 130 or 140octane for that matter (there was a brief comment about 140oct) supposedly these are extremely high octane aviation race fuels (not just regular aviation gas). Anyone else have any experience with this? I have never even heard of it personally.
 
JayHäss said:

How a fuel acts and reacts under extreme cylinder pressures (I.E. 20+lbs of boost) is literally "rocket science". Engineers develop fuels for specific applications. C16 IS a fuel for high boost FI applications. Sunoco Maximal is not...yet it's 117 R+M/2 rated as well and I get knock at 20psi with it.

BTW I just want to point out again that the 125 octane rating is bunch of BS. It's very rare that you will see that, and furthermore that is not a R+M/2 rating. If I'm not mistaken Sunoco Maxima has a 127 motor octane in that case.
I just wanted to point out that with the Sunoco M fuels, I have seen the same thing. Knock comes back even with the higher octane. I have heard of some people complaining of bad gas at some tracks and this could possibly be the reason.
 
greenstreak said:
I have one more project to finish up this week and then it is time to hit the dyno and retune the propane again.
Look forward to it. Thanks Erik.

Joe
 
JayHäss said:


Totally false. Bad information.

C16 is MUCH more stable for high boost environments. Joe Reitman hit the nail on the head and to add to his statement, there is more to knock supression than simply octane. How a fuel acts and reacts under extreme cylinder pressures (I.E. 20+lbs of boost) is literally "rocket science". Engineers develop fuels for specific applications. C16 IS a fuel for high boost FI applications. Sunoco Maximal is not...yet it's 117 R+M/2 rated as well and I get knock at 20psi with it.

BTW I just want to point out again that the 125 octane rating is bunch of BS. It's very rare that you will see that, and furthermore that is not a R+M/2 rating. If I'm not mistaken Sunoco Maxima has a 127 motor octane in that case.
My statement was based on NOT running the propane with C16. To see the most benefits, I would think you would want to run it on pump gas, to see the most boost gains and/or knock suppression.

C16 has a huge octane rating, and is designed for Forced Induction cars.

So you WOULD be hurting yourself running propane (octane rating of slighly under 110, all bullshit aside) with C-16. It's like mixing pump gas and C16, yea it would work, no it wouldn't work good, and WTF would you do it?
 
you havent taken into consideration the cooling properties of propane. from what i have been reading propane is fairly iratic in its octane rating from fill station to fll station so it is kind of hard to nail an oct. rating to it. but i would sacrifice mixing the c16 to gain the cooling effect propane has. i could never run over 20psi on c16 without excessive knock (19-20psi was my max on c16), but now i can run 20+psi on street gas with reasonable knock sums (<7). i dont think you are hurting yourself running propane with c16.
 
DSMu4ia said:


My statement was based on NOT running the propane with C16. To see the most benefits, I would think you would want to run it on pump gas, to see the most boost gains and/or knock suppression.

C16 has a huge octane rating, and is designed for Forced Induction cars.

So you WOULD be hurting yourself running propane (octane rating of slighly under 110, all bullshit aside) with C-16. It's like mixing pump gas and C16, yea it would work, no it wouldn't work good, and WTF would you do it?
Damn, I am so sorry. I totally misunderstood your post. Yes I agree with what you wrote. Sorry about that, didn't mean to flame you. :)
 
eyebrowski said:
you havent taken into consideration the cooling properties of propane. from what i have been reading propane is fairly iratic in its octane rating from fill station to fll station so it is kind of hard to nail an oct. rating to it. but i would sacrifice mixing the c16 to gain the cooling effect propane has. i could never run over 20psi on c16 without excessive knock (19-20psi was my max on c16), but now i can run 20+psi on street gas with reasonable knock sums (<7). i dont think you are hurting yourself running propane with c16.

I don't know too much about cooling properties of Propane, but I do know that running it is NOT to cool the intake charge. It's to gain octane rating for the majority and to suppress knock.

What I do know, there are other reasons why you couldn't get to run 20psi on C16. Boost leak or something, but something isn't right. 20psi on C16 is like, 10psi on 94 octane..heh.
 
that very well may have been the case. so now the debate is, does propane + c16 supress knock better than straight c16? my car is going to be off the road till next spring so i'm not going to be able to make any runs with c16 for awhile... does anyone know if you can get high octane propane anywhere?
 
joereitman said:
"1. A "float valve" that only allows the tank to be filled to 60% of its capacity. The filling station has no possible way to overfill this tank regardless of the knowledge or capabilities of the filling station attendant.

Joe
Just for correct info: The new OPD valve tanks which are now required by law allow 80% tank fill. This keeps the filler from overfilling.
 
eyebrowski said:
you havent taken into consideration the cooling properties of propane. from what i have been reading propane is fairly iratic in its octane rating from fill station to fll station so it is kind of hard to nail an oct. rating to it. but i would sacrifice mixing the c16 to gain the cooling effect propane has. i could never run over 20psi on c16 without excessive knock (19-20psi was my max on c16), but now i can run 20+psi on street gas with reasonable knock sums (<7). i dont think you are hurting yourself running propane with c16.
On Average you will find Propane is 110 octane. Not much higher or lower.
 
Just to add to this post. I know lots are weary of using propane. One main concern running out. You will have to lean out normal fuel when adding Propane to get your O2s back in line. But when you run out of propane you then run into a LEAN condition which we all know is BAD especially at 20+psi...We are not here to sell and have purposefully sat back as this thread on our kit has gone on to 5 pages. But this is a BIG advancement.

Low Propane Early Warning System (EWS)

We have developed the Low Propane Early Warning System. With this option you will have a Bright Red Flashing LED on the dash. It will Start flashing the moment your Propane tank drops below a preset pressure setting warning you that your tank is getting low. It will also warn you if you forget to turn your tank on. This will allow you to run Propane without having to worry if your tank is low.
 
import power on said:
Just to add to this post. I know lots are weary of using propane. One main concern running out. You will have to lean out normal fuel when adding Propane to get your O2s back in line. But when you run out of propane you then run into a LEAN condition which we all know is BAD especially at 20+psi...We are not here to sell and have purposefully sat back as this thread on our kit has gone on to 5 pages. But this is a BIG advancement.

Low Propane Early Warning System (EWS)

We have developed the Low Propane Early Warning System. With this option you will have a Bright Red Flashing LED on the dash. It will Start flashing the moment your Propane tank drops below a preset pressure setting warning you that your tank is getting low. It will also warn you if you forget to turn your tank on. This will allow you to run Propane without having to worry if your tank is low.
That seems like a very good upgrade.
 
IMP- is this availible on your site yet? if not when?
also, maybe you can help us with this...do you have any c16 vs. propane logs? we have come into the debate whether it is better to run c16 or c16 + propane, with the straight c16 you get a 116oct fuel, when you add propane you lose oct. but gain cooler air. which has a better effect on knock?
 
I understand the AFC is leaned out 15-20% in the mid range and top end to accomodate propane. The first question is, how much propane vapor replaces that lost 20% of gasoline to bring us back to appropriate O2? Is it a substantial enough quantity to effect a major temperature decrease in the intake charge?

For example, is the air to propane ratio 11:1, 7:1, 4:1, etc.? If it is as rich as 4:1, and post intercooler air w/o propane is 120, and propane exits the tank at -47*, this would yield decreased IAT by about 42*, to 78*, if my math is right. But, I am just guessing, both on air/propane ratio and on post intercooler temperature. Does anyone know the ratio and average temperature so we can quantify the temperature decrease?

Thanks,

Joe
 
JayHäss said:



C16 is MUCH more stable for high boost environments. How a fuel acts and reacts under extreme cylinder pressures (I.E. 20+lbs of boost) is literally "rocket science". Engineers develop fuels for specific applications. C16 IS a fuel for high boost FI applications.
Here is some info both on C16 and on VP's Performance Unleaded turbo-specific product, from racefuels.com, FWIW...

"C16®:
Used in: Turbocharged engines, blown engines, nitrous oxide and airplane racing/pylon aircraft racers. NHRA Legal for Comp Eliminator; National & FMDRS Events.
Color: Blue / Lead: 6 Grams per gallon / Specific gravity: .730 at 60°F / Motor octane: 117 / Aromatic hydrocarbon content: 10%. / Recommended for blown or turbocharged applications. "

"Performance Unleaded®:
Performance unleaded is well suited for high performance, street legal cars. It meets ASTM D-439 standards and does not contain any metal compounds. Performance unleaded will not harm catalytic converters or oxygen sensors. Performance Unleaded will typically allow turbo engines to raise the boost from the stock 8-10 lbs. to 20-25 lbs. Works well on the latest generation of electronically controlled turbo engines.
Color: Light Yellow / Unleaded / Specific gravity: .760 at 60°F / Octane: R+M by 2: 100 "
 
Correction to air/propane calculation above- it is an assumption based on 3:1, not 4:1. Plus, I can't imagine the mix would be nearly this rich. That figure was arbitrary and picked as an example only.

Joe
 
Discussion starter · #117 ·
Don't know that I will be updating this thread with anything for a while. I whacked a deer at about 50mph in the Talon this week. Needless to say the car will be down for a little while while it is put back together.
 
greenstreak said:
Don't know that I will be updating this thread with anything for a while. I whacked a deer at about 50mph in the Talon this week. Needless to say the car will be down for a little while while it is put back together.
I'm sorry to hear that, hope to hear that you are back on the road soon.
 
Sorry to hear it Erik- glad you are ok.

Joe
 
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