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-   -   80% Pump----- 20% Methanol (https://www.rx7club.com/auxiliary-injection-173/80%25-pump-20%25-methanol-576000/)

Howard Coleman 09-07-06 04:53 PM

80% Pump----- 20% Methanol
 
finally, for me, concept met reality. happily i found both to be similar.

i have finally sorted thru a number of challenges w my car and gotten down to actually running alcohol. while it was just a start and i am sure there will be lots of learning opportunities along the way, i thought i'd share with you all my observations:

my system (ALKYCONTROL) is a 100% alcohol setup. my plan is to remove 20-30% of the pump gas and replace it with methanol. i plan to run at 23 psi on the street and track as that is the sweet spot for my turbos. my two turbos put out 84 pounds per minute, similar to a GT42.

i set my rig up to start spraying alcohol at 5.5 psi boost. after about 5 runs i am impressed as all spray initiated within 100 PIM points. that's a range between 5.35 and 5.49 psi!

i removed 20% from my base fuel across the board from P11 14,600 to P16 21,300. i did a slight transition just before P11.

my AFR transitioned from 12.5 to 10.4 as the spray started and dropped to a low of 9.4 at around 15 psi before raising to 10.1 at 6600.

my egts, (monitor and log on both rotors pre-turbo) started just before the spray at 1111 F, and dipped to 1075 mid-run at afr around mid 9 and then climbed toward the end to 1250. max boost 15.77 psi. max rpm 6600. IGL at modest 13 degrees w 11 degree split. fuel pressure 55psi. injector duty cycle (850/1600) 53%! that's down from the usual 80+%.


inspite of the sub 10 afr the motor ran cleanly since alcohol burns better. no hint of major richness but i will be leaning it out to 10.5 afr.

so far so good. can't wait to turn up the boost and get trimmed out.

stay tuned,

howard coleman

hondahater 09-07-06 05:40 PM

Nice! you guys need to hurry up and tune those things to 23 psi and tell us about it :) On my little alky setup I would love to hit 20psi with no race gas. Guess we'll find out.

scotty305 09-07-06 05:42 PM

That is great news, Howard. More proof that water or meth injection is an especially good idea for turbo rotaries.

I don't quite understand how a wide-band O2 sensor determines the AFR's, but I've always wondered if alternative injection might 'trick' the sensor similar to how a misfire will. Good thing you're monitoring EGT's as well.

-s-

dubulup 09-07-06 05:42 PM

Sounds great!

EGT of 1600F is the high/dangerous side for typical high boosted rotaries on pump fuel, correct?

books 09-07-06 07:27 PM

What were the ambient and intake air temps?

Howard Coleman 09-07-06 07:44 PM

amb was 79. charge air temp was 91. i have my temp sensor relocated just after my intercooler and before the methanol injector nozzles.

howard coleman

books 09-07-06 08:14 PM


Originally Posted by howard coleman
amb was 79. charge air temp was 91. i have my temp sensor relocated just after my intercooler and before the methanol injector nozzles.

howard coleman

thanks, it was fairly warm up there.

I had noticed through a few datalogs that the intake temps seem to affect EGTs.

Did you log any runs without methanol to baseline your EGTs?

Asleep 09-07-06 08:53 PM


Originally Posted by dubulup
Sounds great!

EGT of 1600F is the high/dangerous side for typical high boosted rotaries on pump fuel, correct?

I would say so!

But Howard only mentioned up to the 1200's, right?

Howard, you EGT measurement is pre-turbo, in each runner, correct?

Glad to see your positive results!

After losing another water seal and cracking an apex seal down it's length, I got see the carbon deposits in my block first hand. Wonder how much cleaner this will keep it on the inside?

Tony

RETed 09-07-06 09:09 PM

Don't suppose we can get a pic of your spark plugs pulled? :)


-Ted

Jason 09-07-06 10:47 PM

Alky/Water is the way to go. We have been installing a lot of these lately and recommending them for people running single turbos and high boost.

Jason

nik 09-07-06 11:07 PM

These AFR values, are they taken using a lambda->AFR table for gasoline? If so, is there a reason to tune it richer (10.5) than one would on pure gas? Would it be a good strategy to tune for the same lambda value as one would for pure gasoline?

I think this is a great setup, where you increase the fraction of methanol fuel to suit the antiknock requirements of the engine.

PDViper77 09-08-06 12:16 AM

What is the highest amount of boost you could run on meth/93 octane before it gets risky?

BDC 09-08-06 02:07 AM


Originally Posted by PDViper77
What is the highest amount of boost you could run on meth/93 octane before it gets risky?

We don't know yet, PDViper. That's the high dollar question and it's what Howard and I intend on finding out in the next couple of months. We fully expect this adventure to be a paradigm shift on many levels for the rotary community; a revolutionary kind of thing, more or less.

I don't agree with the alcohol/water mixture theory. Methanol only -- Water is inert in the combustion chamber and does not yield BTU's, therefore there's no change in effective octane of the fuel in the compressed charge. That's what we're trying to combat here -- Hang your hats on this one, folks -> our engines are dying from the auto-ignition of the atomized fuel in the charge during the compression stroke. We're expecting to make killer power on greatly inferior and unreliable fuel (pump gas) that just can't take the heat the rotary engine creates.

Water has a high specific heat index, sure, but this only yields something if it's properly atomized into a mist in the intake, which in and of itself presents a problem. Otherwise, it is inert. It will yield a drop in charge temps but not terribly significantly from what I can see.

Methanol, on the other hand, like it's brother ethanol, provide BTU's during combustion, has as very low flash point at 100% volume (52*F), has an extremely high latent heat of evapouration, and also has an effective octane rating of anywhere from 110 to 140 depending on whom you listen to. Methanol does not require atomization prior in the injection system -> once it hits the intake stream, even at the smallest amounts, it evapourates and significantly cools the charge as effectively as intercooling (ever seen a turbo'd, non-intercooled drag race car running on methanol alone?) Creating a healthy ratio of 80/20 yields race-gas like effective octane with an ambient-like intake charge temp as well as cold manifolds.. Do the math. :)

Howard's posted it a few times, and I'll post it again -- Have a thorough read of this section on TurboBuick.com (Grand National/Turbo Regal website) and look at what they've done! http://www.turbobuick.com/forums/forumdisplay.php?f=14

http://forum.teamfc3s.org/showthread.php?t=50716
http://forum.teamfc3s.org/forumdisplay.php?f=44

B

BDC 09-08-06 02:08 AM


Originally Posted by nik
These AFR values, are they taken using a lambda->AFR table for gasoline? If so, is there a reason to tune it richer (10.5) than one would on pure gas? Would it be a good strategy to tune for the same lambda value as one would for pure gasoline?

I think this is a great setup, where you increase the fraction of methanol fuel to suit the antiknock requirements of the engine.

To answer your question, Nik, let me refer you to 'THE CHART':

http://forum.teamfc3s.org/showthread.php?t=50684

B

Jason 09-08-06 07:48 AM

We have been running 23 lbs on alky and 93 octane for a while with no problems. This is on a half bridge with a T-78.
We did an FC with a GT42, large street port running 21 lbs on pump gas and Alky/water mix.
My EVO runs 30lbs of boost on pump gas and Alky, stock block.

Im sure we could run more boost than 23 but havent had the time to mess with it.

Jason

hondahater 09-08-06 07:50 AM

wow props to you jason! I love hearing stories like that :) I've got a budy with ane evo running tons of boost with his smcenterprises kit and pump gas.

KNONFS 09-08-06 10:31 AM


Originally Posted by howard coleman
finally, for me, concept met reality. happily i found both to be similar.

i have finally sorted thru a number of challenges w my car and gotten down to actually running alcohol. while it was just a start and i am sure there will be lots of learning opportunities along the way, i thought i'd share with you all my observations:

my system (ALKYCONTROL) is a 100% alcohol setup. my plan is to remove 20-30% of the pump gas and replace it with methanol. i plan to run at 23 psi on the street and track as that is the sweet spot for my turbos. my two turbos put out 84 pounds per minute, similar to a GT42.

i set my rig up to start spraying alcohol at 5.5 psi boost. after about 5 runs i am impressed as all spray initiated within 100 PIM points. that's a range between 5.35 and 5.49 psi!

i removed 20% from my base fuel across the board from P11 14,600 to P16 21,300. i did a slight transition just before P11.

my AFR transitioned from 12.5 to 10.4 as the spray started and dropped to a low of 9.4 at around 15 psi before raising to 10.1 at 6600.

my egts, (monitor and log on both rotors pre-turbo) started just before the spray at 1111 F, and dipped to 1075 mid-run at afr around mid 9 and then climbed toward the end to 1250. max boost 15.77 psi. max rpm 6600. IGL at modest 13 degrees w 11 degree split. fuel pressure 55psi. injector duty cycle (850/1600) 53%! that's down from the usual 80+%.


inspite of the sub 10 afr the motor ran cleanly since alcohol burns better. no hint of major richness but i will be leaning it out to 10.5 afr.

so far so good. can't wait to turn up the boost and get trimmed out.

stay tuned,

howard coleman

Thanks for the info, and please, PLEASE keep us posted :)

Quick question though, what is the consumption ratio of methanol vs a full tank of gas? Basically, I trying to figure out how many times does the methanol tanks needs to be filled (or refilled) per a full tank of gas.

blitzboy 09-08-06 10:54 AM

This thread rocks!!!!
Will be changing my basic WI to coolingmist's vari-controller kit to run methonal properly.

Howard are you just running one Nozzle for the methonal or two?

BDC 09-08-06 11:26 AM


Originally Posted by Jason
We have been running 23 lbs on alky and 93 octane for a while with no problems. This is on a half bridge with a T-78.
We did an FC with a GT42, large street port running 21 lbs on pump gas and Alky/water mix.
My EVO runs 30lbs of boost on pump gas and Alky, stock block.

Im sure we could run more boost than 23 but havent had the time to mess with it.

Jason

I'd like more info and proof of this.

Zero R 09-08-06 11:59 AM

The only issue I see with alcohol versus water is, alcohol is corrosive, it can also wash away the oil your using to lube the combustion chamber very easily, we run straight alcohol here on our one car and will be on our other, and we have to use a completely different oil for the premix. While water may have no heat to offer, it is definitely a good det. supressor. Straight water on a good setup will offer a nice safety margin. Not knocking it(alcohol) just throwing out some useful info.

Howard Coleman 09-08-06 12:02 PM

i run two M10 sized nozzles. Julio says two nozzles for above 500 rwhp. my nozzles locate in the silicone coupler immediately infront of the elbow. BDC is running the same setup w one M15 nozzle.

howard coleman

fastcarfreak 09-08-06 12:38 PM

you guys definately rock with your info. The only problem i have is that i use water/meth injection as a safety net. Until i learn to rebuild my own motors, i dont want to risk it, so i do every bit of detonation deterence possible. When you guys get this all figured out perfectly, i will bet there are going to be tons of people following in your foot steps, me most likely included. Keep up the good work.

BDC 09-08-06 12:43 PM


Originally Posted by fastcarfreak
you guys definately rock with your info. The only problem i have is that i use water/meth injection as a safety net. Until i learn to rebuild my own motors, i dont want to risk it, so i do every bit of detonation deterence possible. When you guys get this all figured out perfectly, i will bet there are going to be tons of people following in your foot steps, me most likely included. Keep up the good work.

That's the other angle -- doing an injection system to give a measure of reliability on top of a 100% gasoline setup. I've got a customer, Paul, up in TN that does this. I didn't have an issue going up to 14-15psi on pump with his car, figuring the water injection would add some wiggle room.

B

BNA_ELLIS 09-08-06 03:06 PM

I have run up to 1.7 bar with 50/50 water methanol mix, on my t51 extended port

BDC 09-08-06 04:00 PM


Originally Posted by BNA_ELLIS
I have run up to 1.7 bar with 50/50 water methanol mix, on my t51 extended port

What octane fuel were you using? I wonder if you guys' fuel in the UK is different than here.

B


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