PUMP GAS

[1320 BOWTIE]

How has the addition of 10% ethenol affected performance of pump gas. I drag race a 406 Nova and lost a couple of MPH and a couple of tenths in the quarter and was wondering if it could be the gas.
I.m running 10.14 compression with cast iron heads. Would I benefit by adding toluene to the gas?
I hope this isn't too mundane a question for this great site.
Thank you

[randy331]

Bowtie; Was this a back to back test when you lost the et. ?
This summer I bracket raced a 8.8/1 compression 355" sbc. I ran 87 octane/ 89 octane 10% ethanol/ 91 octane/ 92 octane /one week I was low on fuel and poored in some 112 from a freind. Only one time was it a back to back test. I went to the track on a test night with 91 in the car, later put in 87. I saw no et difference. After that I just put some in a can, when I filled the truck on the way to the track.
I, too, would be interested to here from an expert in the area of fuel on this subject.

Thanks; Randy

[1320 BOWTIE]

Randy,
This was running from one year to the next. But running better weather conditions and same 60 foot times the car ran consistantly a couple of MPH down from the previous year. I even had better 60 foot times and couldn't pull the ET numbers from a year ago.
Everything looked ok when I tore the engine down. The end gap on the top ring had widened .002 from .018-.020
The car is very consistant, it just runs slower.
The only thing that changed was the addition of about 10% ethenol to the gas. I haven't found out if that could be the problem so I thought I'd ask here.

[needforspeed66gt]

Fuel chart - the blended fuel has less energy...how much difference that makes at the track I don't know.

[randy331]

Bowtie; My guess is ethanol blended fuel would require slightly richer jetting than fuel not blended with ethanol. It is my understanding that fuel blended with ethanol has a higher oxygen level than without, and slightly lower BTU level. If this is true, a slight increase in jetting would be
required.
Was the ethanol higher or lower octane than the other fuel?
Your 10.14/1 compression may react differently than my 8.8/1.?
Also, I don't know about the burn rate of ethanol blended fuel verses without ethanol?

I'm by no means a fuel specialist, and would be glad to here from someone more informed than myself.

Thanks; Randy

[randy331]

Thanks; speedy66gt, looks like in the time it takes me to type, you provided an answer.

Are typing speed and drag racing speed linked???????????

Thanks, Randy

[flyin ryan]

two years ago when we first got ethanol (pump) fuel up in my area i did back to back test's on 11 engines on the dyno over an eight month span against the pump gas i've been running for the previous 14 years. result's...i saw an average increase of 5-6 point's (tq/hp) on the low end & a best of 11 point's average. not peak number's...average. no jetting, air bleed, timing change, nothing, just switch jugs. no engine ever lost, 5-6 increase was the worst i saw. i was sold. still am. the car's on the track are a tick better as well, not a lot but a little. mostly mid to high 9 second street car's naturally asperated. take it for what it's worth. just my observation's.

[needforspeed66gt]

Burn rates are different and creates a longer "push" rather than a quick one??

[Cobra]

Ethanol is hygroscopic and you may have absorbed enough water into your fuel to affect performance. Simply spoken, gasoline with 10% ethanol does not possess the energy of pure gasoline. Ethanol is highly corrosive to materials found in some older model vehicles. Newer vehicles and fuel components have been engineered to work with ethanol. Gasoline with added ethanol also has additives to combat potential problems. As seen with E-85, alcohol based fuels can work in a performance environment. With E-85, performance may outweigh losses in fuel economy.

[1320 BOWTIE]

I had fattened the jetting up to 5 steps in both primaries y & secondaries without picking up any MPH.
A leak down test showed a loss of 9-10%. Compression test gave me a reading of about 200.
The engine has 3600 miles on it with 267 passes in the quarter mile.

[Cobra]

You know your performance with 10% ethanol so all you need to do is fill car with gasoline containing no ethanol and run it down the strip.

[1320 BOWTIE]

I plan to play with it at test & tune dates before the points season begins.

[hotrod]

In theory it should make only slight differences. We have been running ethanol oxygenated fuels here in Denver Longer that any city in the U.S. (since the 1980's) and it would take some carefully controlled tests to pin down the differences. I personally found that engines tended to run a bit better in the winter time on the 10% blend than they did on the summer blend but is was a very very small difference.

Ethanol has 72% of the energy on a gallon for gallon basis as gasoline, but it is capable of generating more power. At 85% blend you find in E85 the typical difference is 5% -8% increase in power with proper jetting.
At a 10% ethanol blend the fuel energy per gallon is down 3% compared to gasoline, but the following study shows the performance does not necessarily track with fuel energy content due to other effects.

http://www.ethanol.org/documents/ACEFue ... dy_001.pdf

At a 10% blend you have increased the fuel oxygen by approximately 3%. In tests done back in the 1970's this very slight leaning was detectable, on a wideband and accounted for the improved emissions of the typically rich mixtures run at that time.

In modern tests the results are mixed at 3% oxygen added the increase in power/torque is just detectable but varies from car to car based on the compression ratio, timing maps and fuel mixture. The presence of the ethanol will increase the evaporative cooling of the fuel in the intake manifold (one of the sources of improved performance in spite of the lower energy content per gallon). It will also slightly reduce the work the engine does in compression due to the higher cooling.

In tests run at Univ. of Michigan, ignition advance for the ethanol fuels is essentially identical to normal gasoline, but due to higher octane in the higher blends like E85 many can get away with higher ignition advances.

You may want to add a couple degrees of timing and see what happens.

You may also want to replace your fuel filters. Ethanol is a very effective fuel system cleaner and when we made the conversion a lot of cars plugged up fuel filters until they got all the varnish build up out of the system from years of running straight gasoline.

I currently am running 3 different cars on high ethanol fuel blends. One has been converted to E85 and the other two run from 30% -50% blends of E85 and gasoline. If its tuned right for the fuel you should see no drop in performance only a slight increase in torque, and power with a bit cooler engine temps.

Larry

[quickd100]

I ran straight E-85 in my 440 dodge truck for 2 years. I reworked a thermoquad to run it. I never got it on a dyno but it did feel stronger by the seat of my pants. A local engine builder screwed together 2 E-85 street motors for custombers last summer. He dynoed one motor back to back using gasoline and E-85, it was a 500ish hp motor. The E-85 made 20-25 more hp.
As far as the hydroscopic aspect, in 2 years I had zero problems, the truck sat with fuel in the system from Sept. to May. No signs of corrosion, no moisture problems. Carb looked as good as any gas carb. Dave

[putztastics]

hey D, how's that Hemi doing?

I'm wondering why you switched from the E-85 Holley to the E-85 TQ?

Were there problems with the Holley?