alky injection

1984grandnat

Member
Joined
Oct 28, 2001
My first attempt at alcohol injection has been, well...disappointing. I have learned that it takes a little time to get it tuned, but I thought I should see SOME improvement just by installing the thing. All I have seen is either NO improvement, or BOGS!

Built my own kit using old elec fuel pump, adjustable pressure switch, aftermarket overflow reservoir, some 5/16 fuel hose, and a straight NOS nozzle and jet. I am using a mixture of denatured alcohol and distilled water (about 60% water). I can only seem to manage about 10 or 11 psi boost with 91 octane. Little if any improvement with the alcohol. Seems to run a little sloppier with the alky on, a little more responsive without it. No difference in boost either way. Any ideas?

A little more info:

Chip timing, about 27 degrees (is this too much?)
Fuel pressure, about 41 psi
Wastegate rod, set to about 14 psi, but pulls back to 10 or 11,
alky or not.
Valve on alcohol supply line to adjust the volume of alky.
NO knock gauge.

My biggest concern with the alcohol system is that the nozzle is not the FOGGER type, so it sort of "squirts" the mixture into the intake pipe (without atomizing it at all). Although, I have heard of people running injection systems with only windshield washer pumps, and I don't think these little pumps put out the pressure it takes to atomize, and these systems are working! I placed the nozzle in the intake pipe, just after the MAF sensor, so it has about 18 inches before it gets to the throttle body (which should help the atomization, right)?

Anyway, if anyone has any info they can share, please let me know! Thanks in advance.
 
27* is a race chip!!! Becarefull...and I hope you have a 307/340 in the tank and a scantool to watch o2's and knock.

Just a little FYI - your nozzle placement may seem like a good idea but, alky is very corrosive and will eat the carbon seal in your compressor housing in no time. I also hope that fuel pump is rated for alky use too.....high boost and a seized pump = bad things.

A good tuned stock hotair should be able to see 14-15psi with no probelms. Please post your combo. We should be able to help you but without a scantool - your playing with fire.
 
wow,big problems brewing here.

first,you need a scantool.or at least someway to monitor knock.

27 degrees is waaaaay to friggin much timing.

pissing alky into your intake pipe is not a good plan.that means it has to pass thru your turbo before it can go into your intake.that's bad.take your turbo to intake adapter out and drill/tap it and screw your jets in there.

get some jets that will atomize your alky.

also,let us know what other mods you have.

later,sean
 
MODS

Okay, here we go, hehe:

Walbro performance fuel pump (from Kirban)
Pump hotwire kit (8 gauge wire from alternator)
Kenne Bell ram air kit
Adjustable fuel pressure regulator
Access to custom-made chips
No scantool or knock gauge
Can't get any good info from T-Link (tried)
87 ECM conversion (obviously) and MAT sensor
87 coil pack (new)
84 MAF sensor and 84 coil module
Adjustable wastegate actuator rod
Hooker 2 1/2 inch dual exhaust, no cat
Stock headers, pipes, turbo, intake, heads, injectors, cam

Although I have no knock gauge, I can tell the ECM is retarding timing and boost. At WOT, it hits maybe 14 psi, then falls to about 10, and when I let off the throttle slightly, the turbo changes pitch and the boost tries to climb again. I get back in it, and the boost falls. Cannot hear any audible knock, but I don't push it that hard. I have another chip handy with about 19 degrees advance. Does this sound a little closer to where I should be? I would like to know about where everyone else is running in terms of timing and boost, so without any data from my car, I can at least get it close.
 
Plug T-link backing and set it for the 87 ecm - that should fix the werid numbers. IF that doesn't you might have some probelms elsewhere.

It sounds like the is pulling timing and that isn't good. Stick the 19* chip in and try again.

BTW - I run 20psi on straight 94 octane but, I have an intercooler.
 
Went back to 19 degree chip. Also went to 93 octane gas, instead of 91. Did some re-adjusting on alcohol system and wastegate and without alky, can hold 14 psi boost. When the alky is on, can see up to 16 psi. Looks like the stuff is tryin' to work at least, hehe. Doesn't seem to be pulling boost back nearly as bad now, but still not where it needs to be. Next investment: Knock gauge! Also, have heard lotsa talk about Scantools. Can anyone recommend any good (not TOO expensive) brands and models, and where I can get one?
 
Top