Originally Posted by flanders

I thought 12 or even lower was beneficial, but I guess it's best to test yourself on each car and setup.
Thanks for your input

Originally Posted by b.r.i.a.n.

This afternoon, I retuned my AP1 once again. Since the last time, a few things have changed. I swapped the Haltech Sport 1000 ecu in favor of the Pro Plug In. I swapped over the 70mm throttle body in favor of a 74mm throttle body. I got rid of the velocity stack and just went with a 3.5 inch filter. I changed the 2.5 inch test pipe to 3 inch and I also added a fuel composition sensor. For those of you who did not see my previous thread, here's the link:

https://www.s2ki.com/s2000/topic/909...tepped-intake/

At the moment the car has the following modifications:

diy stepped 3.5 inch to 3 inch intake with injen filter
- skunk2 74mm throttle body
- hondata intake manifold gasket
- plm header and 3 inch test pipe
- hks 3 inch single exhaust
- injector dynamic 1000cc injectors
- E85 fuel
- Haltech Pro Plug In ecu
- fuel composition sensor

The main reason for retuning apart from the minor bolt on changes is to do a comparison between pump gasoline and E85 fuel. There was still some ethanol in the tank when I poured some gasoline. I was able to get the ethanol blend down to 18%. I've seen the local gas stations averaging 9-10% ethanol in their gasoline. I tuned the car on E18 and the engine yielded 220-221 whp.

I then poured in 10 gallons of pump E85 from the local U-Gas. There was still some gasoline in the gas tank and after 10 gallons of E85 the mixture came out to E63. I have seen an average of 77-80% ethanol in the E85 sold at the local U-Gas. Had I drained the tank I may have seen that amount. The engine was retuned on the spot with the E63 blend.

The red and green line were the last two passes made on the E18 blend. The blue and black lines are the last two passes made on the E63 blend. As you can see, a 45% increases in ethanol yielded a gain of approximately 5-6 whp. I'm sure another 2 whp could have been squeezed out with the ethanol content closer to 80%.

So in conclusion, yes, even with a naturally aspirated engine the hype is real.

Originally Posted by Mrsideways

The Local Citgo station has E85 and the rumor is it's owned/operated by a drag racer who's very diligent about his E85 mix. So I grabbed some last night and brought it home and tested it and got it at 88% ethanol. I tested it twice to be sure and it came back the same. Excited to find that.

Originally Posted by b.r.i.a.n.

Did you use one of those fuel test tubes that you mix with water? If so, I've noticed that those test tubes read a little high with regards to ethanol content. I prefer the fuel composition sensor.

Originally Posted by yamahaSHO

They'll both be wrong if water was already absorbed.