Diesel / CNG discuss

ethanol is high octane. Makes awesome power too. The 1.8T that was in my vw went from 300 to 350hp switching to e100 and re-tuning.
 
EFI setup? I know a couple racers that tried E85 on carb setups and it wasn't worth the hassle to them.
 
JWhite said:
EFI setup? I know a couple racers that tried E85 on carb setups and it wasn't worth the hassle to them.
Click to expand...

I haven't known anyone to try with carbs. You have to flow so much more fuel, I can't imagine the amount of stuff you'd have to change/re-tune with a carb'd system.

I suppose if the guy didn't already have capable injectors, he would have had to swap them, but that was it.
 
Last edited:
I was thinking on running E85 in my circle track Ranger EFI. The cooling effect the alcohol has places a benefit in the mix. Yes either way with injectors or carburetor you need to use more fuel so therefore the whole carb needs to be fitted accordingly different. If you look back into the 90s and you look at Mark Thomas in IHRA Funny car he ran Ethanol and has several championships. Just like a gasoline carb, it takes tuning practice.

Going back to CNG and to the comment of burning hotter, I feel the combination burns the same however it is able to release power over a window that better suits torque output and burns cleaner with leads back to more complete combustion.
 
I always see in increase in EGTs when I turn on my CNG its not much of an increase but average would be 100 deg.
 
Perhaps higher egts be a result of continued burn once the valve is open? Not sure when a exhaust valve is open in relation to crank angle :pop:
 
If one had enough specs from the stock cam, that would be easy to figure out.

Like I said, the lbz I tuned with a CNG setup, I took out almost 30% injector pulse up top to keep the WOT egts in check. That is with increased timing also.
 
I will say this with the 467.7 I am now running my egts are much cooler now, having plenty of air for the fuel I have available even with the CNG in the mix. The only time I have a problem with smoke in my tune is down low in rpms with the cng turned on, too much fuel then. WOT I am under 1150 EGT with the CNG on.
 
I have been working on that as time permits me. Its much better now than two years ago with my old smarty me tunes.
 
JWhite on the systems or trucks you have messed with how are they introducing the CNG into the engine ? Direct injection or through the turbo? What type of low pressure regulators are they using?
 
I'll have to ask on the specific brand (I was thinking impco) but Kaseys lbz is using a vacuum regulator. It introduces CNG into the turbo inlet, so there is lag to an extent. Marc Deluca does have a controller setup to use a higher pressure regulator and injects it into the manifold, of course this setup is more expensive, and you change the throttle table to only inject 1-5mm3 up to 50% throttle input and the CNG controller flows more with pedal input. Throttle table ramps up smooth from 50-100% so it drives normal with no CNG.

How do you have yours set up?
 
I run 2 high pressure regulators the first cuts tank pressure to 450 psig the secound cuts that to 275 psig. That feeds an impco low pressure reg that feeds the turbo. The flow of CNG is dictated by the turbos. The more the turbo draws ( spools) in the more CNG is feed to it. My system is pretty simple. My fuel mileage is impressive as well. With the smarty I used to run I was able to drive from Columbus Ohio to Wills Texas on about 13/16th of a tank of diesel. Over 1280 limes on that tank.
 
Sounds like a similar setup, I was wrong on the brand, he said its a tescom and meco setup.
 
Mine is set to negative pressure meaning their is no flow unless the turbo is drawing air in. This has been the hardest part of setting up the complete system, I am still working on perfecting that spring.
 
Yea, you need some sort of pressure to flow gas. Or you just using it as a check valve more or less?
 
You must log in or register to reply here.
Back
Top