Pre-turbo methanol injection results (vbox results)
06-10-2017, 01:42 PM
#1
Pre-turbo methanol injection results (vbox results) Not an LS but I figured more people are interested here than anywhere in methanol and water injection. My other car has an LS in it.
This car is a 63 Impala with a 454 bbc and AFR 265 heads. Turbos are cheapest S300 60mm fockers you can get.
I put it together with no intercooler and no injection. Its blow through carb and locked 40* timing (never a speck on the plugs, the timing seems high but is good at 40*). The turbos are mounted behind the top of the radiator with the compressors facing each other, the worst possible spot to draw air from, probably 130-140* inlet air into the compressors.
Long story longer, I ran back to back on the freeway a few times with methanol injection into the turbos and not, all the same cruise, I have button to turn on the injection, the VBOX results are super repeatable and accurate but I know it still seems strange. I'd floor it around 75 and let out a little over 110, so chose 90-110mph intervals to compare. All comparisons are done in th400 top gear with 3.08 diff gear. The rpm range is roughly 3800-4500 to go from 90-110. The boost gauge shows 8psi with and without injection.
no injection 90-110 2.69s
injection 90-110 2.36s
.33 difference in a 20mph interval is pretty big, the injection is amazing. Obviously this setup with no intercooler and sucking in hot radiator air will benefit from injection the most but its better than I expected.
My injection is 30% water and 70% methanol with an M15 about 5" from each turbo inlet, so 30gph total of injection.
Doing my special monkeying with Wallace drag simulator the no injection shows 670wtq and the injection shows 735wtq, a 65wtq improvement with the injection if those numbers are close.
Take it all with a few grains of salt.
This car is a 63 Impala with a 454 bbc and AFR 265 heads. Turbos are cheapest S300 60mm fockers you can get.
I put it together with no intercooler and no injection. Its blow through carb and locked 40* timing (never a speck on the plugs, the timing seems high but is good at 40*). The turbos are mounted behind the top of the radiator with the compressors facing each other, the worst possible spot to draw air from, probably 130-140* inlet air into the compressors.
Long story longer, I ran back to back on the freeway a few times with methanol injection into the turbos and not, all the same cruise, I have button to turn on the injection, the VBOX results are super repeatable and accurate but I know it still seems strange. I'd floor it around 75 and let out a little over 110, so chose 90-110mph intervals to compare. All comparisons are done in th400 top gear with 3.08 diff gear. The rpm range is roughly 3800-4500 to go from 90-110. The boost gauge shows 8psi with and without injection.
no injection 90-110 2.69s
injection 90-110 2.36s
.33 difference in a 20mph interval is pretty big, the injection is amazing. Obviously this setup with no intercooler and sucking in hot radiator air will benefit from injection the most but its better than I expected.
My injection is 30% water and 70% methanol with an M15 about 5" from each turbo inlet, so 30gph total of injection.
Doing my special monkeying with Wallace drag simulator the no injection shows 670wtq and the injection shows 735wtq, a 65wtq improvement with the injection if those numbers are close.
Take it all with a few grains of salt.
06-10-2017, 03:46 PM
#6
Around 8.4:1 compression and I run 15% methanol with 93 octane gas, so should be equivalent of 97 octane, and it smells good too! 40 degrees sounds nuts to me too but it runs noticeably better there than 36 degrees. Ive done a few 0-120 pulls on the street but I always make sure the coolant is under 180.
06-10-2017, 03:49 PM
#7
Around 8.4:1 compression and I run 15% methanol with 93 octane gas, so should be equivalent of 97 octane, and it smells good too! 40 degrees sounds nuts to me too but it runs noticeably better there than 36 degrees. Ive done a few 0-120 pulls on the street but I always make sure the coolant is under 180.
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06-10-2017, 05:29 PM
#9
No idea on the charge temps, no datalogging or IAT gauge. Going by matchbot, just changing ambient temp from 120 to 60 the charge temps go from 200 to 130. Im not sure if the injection really is equivalent to 60 degree air going into the compressor but seems like it would be close spraying an M15 into each turbo with the 2/3 of the liquid being methanol.
One interesting thing is the AFR really didn't change, and the boost didn't change, I might have gained half a pound, but just looking at the gauge it looked VERY close with and without. No change in tune. I have button I press for the methanol so I tried it back and forth multiple times. The AFR isn't changing much at all, maybe 1/3 a point richer, even though I am injecting 20gph of methanol, I figure the air is just that much denser but with the same boost psi it isn't pulling any more fuel out of the carb. The 20gph methanol is making up for it I guess.
One interesting thing is the AFR really didn't change, and the boost didn't change, I might have gained half a pound, but just looking at the gauge it looked VERY close with and without. No change in tune. I have button I press for the methanol so I tried it back and forth multiple times. The AFR isn't changing much at all, maybe 1/3 a point richer, even though I am injecting 20gph of methanol, I figure the air is just that much denser but with the same boost psi it isn't pulling any more fuel out of the carb. The 20gph methanol is making up for it I guess.
06-12-2017, 01:26 PM
#10
The methanol makes the turbo more efficient so it's making better use of the boost you throw at it. Betting if you could read boost pressure in tenths or so you'd see the boost pressure is rising.
IAT sensors would just muddy things up with false readings.
Good rule of thumb is for 1000HP worth of air 100lb/min or so you'll drop 15* for each 8gph of 100% methanol. Double those results for 500hp worth of air flow.
Throwing water in there gets tricky since it pulls more heat, but has a much higher boiling point. I'm sure the water is cooling down the CC a ton thou. Sounds like a fun setup!
Would be neat to see if getting cooler air supplied to the turbos would pick up even more on the VBOX. I'm sure it would but I'm not sure if it would be a night/day difference like many claim.
Get you some HVAC ducting and let us know! You can get the flexible joint stuff and the DIY medical grade cast wrap for broken limbs and make up a super strong induction ducting quick and easy.
Casting material link.
IAT sensors would just muddy things up with false readings.
Good rule of thumb is for 1000HP worth of air 100lb/min or so you'll drop 15* for each 8gph of 100% methanol. Double those results for 500hp worth of air flow.
Throwing water in there gets tricky since it pulls more heat, but has a much higher boiling point. I'm sure the water is cooling down the CC a ton thou. Sounds like a fun setup!
Would be neat to see if getting cooler air supplied to the turbos would pick up even more on the VBOX. I'm sure it would but I'm not sure if it would be a night/day difference like many claim.
Get you some HVAC ducting and let us know! You can get the flexible joint stuff and the DIY medical grade cast wrap for broken limbs and make up a super strong induction ducting quick and easy.
Casting material link.
06-14-2017, 09:40 AM
#11
TECH Fanatic
you havent tuned a bbc before. i had a 468 with 12.5:1 cr and ran 40* locked on 93 and drove it to work and all over the place. BBCs have huge lazy chambers.
06-14-2017, 12:43 PM
#13
I exploded an engine doing this. Didn't work for me, IAT was 190 IIRC. Tried for a few hours and finally made a pull and split the block from pre ignition.
Hacked up my front end on my 54 chev panel for an ebay intercooler and run ambient.
Hacked up my front end on my 54 chev panel for an ebay intercooler and run ambient.
