Digi7ech

iTrader: (1)

I just want to see what others have run to get through the tests.

I just heard one guy say he used 1 gallon of denatured alcohol with an estimated 4 gallons of gas.

Also does anyone know the math/science behind this.

Also do the AFR's change to richer on a stock O2 or do they show leaner?

Thx guys.

Digi7ech

iTrader: (1)

Updated but the damn database kept crashing

jackhild59

iTrader: (7)

i did alot of research on alcohol, gasohol etc when I was trying to pass emission in my 90 na. Don't get too hung up on the octane issues, or if it burns slower of faster or cooler. That is not how the alcohol works to reduce HC's.

Basically alcohol added to gasoline is a way of oxygenating the fuel. Most fuel in the US is now oxygenated to some degree by some process. In Dallas, we have 10% MTBE, methyl, tertiary butyl ether (Whew!). The bottom line is that the alcohol contains lots of oxygen; much more than the gasoline it replaces. So the higher the percentage of alcohol, the more oxygen that is chemically available to the combustion process. And it is available closer to the chemical reaction, as it is already a part of the molecule.

I found lots of info on 10%/90% alcohol/gasoline mix, I found a lot on E85 which is 85% alcohol/15% gasoline.

I deduced that I could go up to about 25% before having any operational problems and that I would probably get about 30% reduction in unburned HC. The downside for me is that 30% just got me a little closer but not over the top.

The bottom line is to pass, however you can pass. Just pass. If you have a test that is withing 25-30%, give alcohol a try. If you are not that close, don't bother. Do something else first.

For me a new catalytic converted was just what the doctor ordered.

Digi7ech

iTrader: (1)

Should I be concerned on detonating and blowing my engine when they drive it?

The guys have a 1-2 gear ramp they have to accel for the dyno and I think he get;s to about 4-5k rpm. I doubt he gets into much boost maybe 1-2psi since the cat and **** really reduce the boost.

Here are my numbers from this morning.
WHich included 1 900 ml bottle of isipropyl alcohol.

Hydrocarbons 1.85 // max 1.60
Carbon Monoxide 20.16 // Max 15.00
Oxides of Nitrogen 1.09 // Max 2.50

I'm thinking I am pretty close so maybe running 1/2 gallon to 6 gallons of gas isn't bad.
If the detonation worry isn't big then maybe I'll just go with the full gallon of denatired alcohol.
I kind of have to pass tomorrow since I have to pull all this stuff off for the drive to sevenstock.

'89Vert

He's not going to be hitting too much boost, it shouldn't blow your car with the previously mentioned mixture. Just take it easy driving there and as soon as you're done fill 'er up with the good stuff and you should be ok, again, just my experience...

Digi7ech

iTrader: (1)

cross reference to my other thread with results.

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/emissions-equipment-install-quick-run-467573/

misterstyx69

iTrader: (142)

the alcohol and gas mix burns at a higher temp..you could end up getting pushed off the dyno!..also..home depot...denatured alcohol...or methyl hydrate..there are threads on this in the second gen forum...at your own risk...p.s..rubbing alcohol ..it's a no no....and if you do this, do it when you are almost empty so right after the test you go for a fill-up to dilute the mix in the tank because the alcohol will eat at your fuel lines!good luck study hard..you'll pass with flying colors..15 minutes shouldn't hurt..read son!