E85

[Jking24]

Putting this post in this section due to the lack of activity in the powetrain section. For those of you that have alot of first hand experience running e85 in non crate applications. Have you experienced the engine not wanting to turn higher rpms when it's too rich. No breaking up or sputtering. Just seeming to kinda hit a wall or ceiling so to speak with rpm. For example you can turn 8300 Evernight with no issues but whenever you put more gear (20+points) to it for say time trials. Some nights it turns 85-8600 and some nights it only turns 8400. This engine is 100% mechanically healthy and is also built to Be able to turned the rpm being asked of it. We have strapped it to a chassis dyno several times and it will turn whatever you want it to and the curves look good but the chassis dyno does not load the engine like it is on track. I'm looking for info from people with first hand experience running e85 thanks in advance

[billetbirdcage]

Putting this post in this section due to the lack of activity in the powetrain section. For those of you that have alot of first hand experience running e85 in non crate applications. Have you experienced the engine not wanting to turn higher rpms when it's too rich. No breaking up or sputtering. Just seeming to kinda hit a wall or ceiling so to speak with rpm. For example you can turn 8300 Evernight with no issues but whenever you put more gear (20+points) to it for say time trials. Some nights it turns 85-8600 and some nights it only turns 8400. This engine is 100% mechanically healthy and is also built to Be able to turned the rpm being asked of it. We have strapped it to a chassis dyno several times and it will turn whatever you want it to and the curves look good but the chassis dyno does not load the engine like it is on track. I'm looking for info from people with first hand experience running e85 thanks in advance

Can't say I've experienced that with e85 but haven't ran E85 on a lot of dirt track stuff besides a crate which doesn't get to those RPM's.

I'm gonna say it would more likely be Fuel volume issue then the actual fuel type. Did you monitor fuel ratio on the chassis dyno or have a wide band O2 sensor and did it go lean at 8000+?

I've seen this with alky before on my dyno when I first started out, with a mechanical holley fuel pump I ran on the cars back then (seemed to run fine on track - mostly slick) but on dyno couldn't make more then 560 to 580HP with one of those pumps and couldn't here the motor lay over but saw it on the fuel ratio. Dumped the mechanical pump and installed a electric system just for the dyno and power jumped way up.

Running too small a needle and seat and just a ton of pressure will cause a bunch of aeration of the fuel that can show up as lean at high rpm. I used large needles and seats (also BLP bottom feel needles) and way lower pressures, like usually under 6#.

[Jking24]

Can't say I've experienced that with e85 but haven't ran E85 on a lot of dirt track stuff besides a crate which doesn't get to those RPM's.I'm gonna say it would more likely be Fuel volume issue then the actual fuel type. Did you monitor fuel ratio on the chassis dyno or have a wide band O2 sensor and did it go lean at 8000+?I've seen this with alky before on my dyno when I first started out, with a mechanical holley fuel pump I ran on the cars back then (seemed to run fine on track - mostly slick) but on dyno couldn't make more then 560 to 580HP with one of those pumps and couldn't here the motor lay over but saw it on the fuel ratio. Dumped the mechanical pump and installed a electric system just for the dyno and power jumped way up.Running too small a needle and seat and just a ton of pressure will cause a bunch of aeration of the fuel that can show up as lean at high rpm. I used large needles and seats (also BLP bottom feel needles) and way lower pressures, like usually under 6#.

Thanks for the input billet. It has plenty of fuel system kse tandemx the bigger one. Fuel pressure is solid all the way through. Carb is from a well known builder with plenty of e85 experience. I don't remember the needle size off the top of my head but I believe it's the same as my alchohol carbs. I've had a afr monitor on it both on the dyno and at the track on a test day. The fuel curve trends rich at the top of the pull. Also the days that it runs better seem to be "good air" days have played with bleeds with no noticeable change. The engine also doesn't like to run alot of water temp without things like tape/ 2 blade fan thermostat etc. All my alchohol experience tells me this thing is rich. I'm 4-5 jets down from where the builder put it and feel like it needs at least that much more. Carb guy says the Carb is too small but it's the same as my alchohol and gas stuff. The Engine builder claims he would've sold me an even smaller Carb so.... oh and yes we've turned it on the dyno past where I'm attempting to go on the track and no problems. Problem is on the dyno at least the one I have access to the loading isn't the same so the air fuel ratio is different. It actually reads really lean on the dyno then you go to the track with a slower acceleration rate/ more load and it's rich.

[MasterSbilt_Racer]

I had similar problems but mine was going lean late on the straight. I changed high speed bleeds to fix it. Installed AFR sensor, put it all in a box, and aimed a go pro at it.

Problem came back last year when we used a different fuel pump that apparently had less volume.

[Jking24]

I had similar problems but mine was going lean late on the straight. I changed high speed bleeds to fix it. Installed AFR sensor, put it all in a box, and aimed a go pro at it.Problem came back last year when we used a different fuel pump that apparently had less volume.

what kind of afr numbers where you seeing when it's running good? Mine definitely trends rich. My afr monitor has a data logger so I'm at least confident in the trend

[MasterSbilt_Racer]

what kind of afr numbers where you seeing when it's running good? Mine definitely trends rich. My afr monitor has a data logger so I'm at least confident in the trend

We were right around 8, iirc. Maybe 8.1, on an E85 scale, at WOT. It's been a couple of years since I messed with that issue.

[Lizardracing]

I've been on E85 for years now and don't have any problems at all. Home built junk to some but it's a 406 making 650ish at 8000 on a mechanical block mounted pump and a dead head regulator. Pump E85.

You didn't give enough details for me to make any sorta meaningful opinion on but I will say this, the right plug and the right coil makes it or breaks the fuel and I've seen it a bunch of times. My engine runs way better at 200 than it does at 170 or less. I'm often taping up the radiator to get to 200 even in the heat of summer. I'll also add a lot of so called E85 carb guys, even big names, are converting alky carbs to E85 and while it works, it brings it's own set of problems because its a different animal altogether. It's easy to get along with E85 but tuning it like gas/alky usually ends up in a bunch of broke stuff.

[LRtireCHANGER]

E85 does not vaporize as quickly as any gas fuel...........I wonder if e85 is not vaporzing for you at higher rpms????? e85 is also harder to ignite than any gas fuel, I wonder if ignition could be a problem over 7000 rpms, because as was earlier stated, not many open motor guys have much experience with e85. Other than those 2, I don't have a clue, I am watching for responses because I am curious.

[billetbirdcage]

While it's not E85 but on gas engines.

One a smaller spec type engine (700HP) Builder said 8800 but in the car it seems to stop at 8200/8300. Did same thing you did add some gear and still turned same RPM and just came to the conclusion it didn't make power at that high an RPM to see a increase. Broke a dry sump belt so builder look at it to be sure and they redyno'ed it and ran it all the way to 9K on dyno and said it went there no problem.

Another large open engine (900+) that I know other guys turn the same motor 9200 in qualifying and ours seems to stop at 8500/8600. I typically run the smaller carb but even with the bigger one it didn't seem to matter but only did that once and have since fixed some other issues. I had as much as .3 more gear then the Lucas guys and turning similar or slightly less RPM and you know they was carrying more MPH then us, lol.

In both of these cases adding gear never seemed to increase RPM once you reach those points. These 2 may be carb or carb size related, but haven't sorted that out yet.

Not sure that helps you, but I have ran into that just no with E85.

[billetbirdcage]

Not sure what your running for plug gap, but you can kill 50HP and a ton of RPM out of a motor with too large for your ignition and never hear it on the dyno or track. You might try closing it down to .030 max and see if you see a change. I've never seen an increase from going to the larger gaps with an MSD type ignition.

I did change from a MSD 6 to a 7 on both of those motors I listed and it did seem to help, but haven't tried more gear on them yet to increase RPM. I just sort of been staying in the RPM range they liked before.

[LRtireCHANGER]

billetbirdcage, I was waiting on your response. I kinda suspected the e85 might not yield a whole lot of improvement in open motors. I think alot of people fail to realize that open motor late models USUALLY have more power than the track can handle. Some tracks are tacky early on, but by feature time, most tracks cannot handle open motor hp.

[Jking24]

While it's not E85 but on gas engines. One a smaller spec type engine (700HP) Builder said 8800 but in the car it seems to stop at 8200/8300. Did same thing you did add some gear and still turned same RPM and just came to the conclusion it didn't make power at that high an RPM to see a increase. Broke a dry sump belt so builder look at it to be sure and they redyno'ed it and ran it all the way to 9K on dyno and said it went there no problem. Another large open engine (900+) that I know other guys turn the same motor 9200 in qualifying and ours seems to stop at 8500/8600. I typically run the smaller carb but even with the bigger one it didn't seem to matter but only did that once and have since fixed some other issues. I had as much as .3 more gear then the Lucas guys and turning similar or slightly less RPM and you know they was carrying more MPH then us, lol.In both of these cases adding gear never seemed to increase RPM once you reach those points. These 2 may be carb or carb size related, but haven't sorted that out yet. Not sure that helps you, but I have ran into that just no with E85.

Billet you may very well be right I have friends with similar combos that do the same. One thing that is definitely different on mine is the intake. When dynoed it shows no signs of nosing over but that doesn't necessarily mean it will keep pulling at the higher load. The biggest problem out not a problem is it runs great otherwise and the plugs look great aswell. I have for the most part settled that it just is what it is. But it's winter time and my gears are turning lol

[Jking24]

I've been on E85 for years now and don't have any problems at all. Home built junk to some but it's a 406 making 650ish at 8000 on a mechanical block mounted pump and a dead head regulator. Pump E85.You didn't give enough details for me to make any sorta meaningful opinion on but I will say this, the right plug and the right coil makes it or breaks the fuel and I've seen it a bunch of times. My engine runs way better at 200 than it does at 170 or less. I'm often taping up the radiator to get to 200 even in the heat of summer. I'll also add a lot of so called E85 carb guys, even big names, are converting alky carbs to E85 and while it works, it brings it's own set of problems because its a different animal altogether. It's easy to get along with E85 but tuning it like gas/alky usually ends up in a bunch of broke stuff.

What kinds of details would help? 6al analog box hvc coil ngk-9 gapped .030-.033, water temp typically 185-190 run a 2 blade fan and 3-6" of tape on the radiator most nights. is definitely not a converted methanol carb. 1-11/16 plate 1-3/8 ventures. When dynoed and on the track the afr curve is really flat throughout the range trending slightly richer roughly a half a ratio or less from mid rpm to peak. Around 12.2 to 11.8 in the gas scale.

[Lizardracing]

My guy will say "Wrong plug and Wrong coil" right off the bat.
HVC2 and NGK -7 plug only.

[Jking24]

My guy will say "Wrong plug and Wrong coil" right off the bat.HVC2 and NGK -7 plug only.

The hvc2 is only recommended to be used on 7 and 8 boxes. I'm not arguing this is just the reason why I have the hvc blaster. It is what msd recommends for 6al compatibility. As far as the plug goes I'm not against trying a hotter plug but my plugs show no signs of being too cold or fouling. It takes 2 to 3 nights of racing before they show any color on the porcelain. The timing mark looks great. We also run the same setup on methanol with no issues. Again I'm not being argumentative I'm just trying to process all the info logically. I appreciate The input.

[Lizardracing]

I know, I'm not offended at all. I don't know it all, don't want to know it all either lol.
Sometimes when E gets too rich, the plugs look better because it's a cleaner by nature. It'll wash away the evidence. So does meth, when you get too rich on meth, you get blubber, on E, you get blown up ring lands and everyone blames the fuel. E is just....different.

All I can really say is throw out everything you think you know about gas and meth. You can't apply gas and Meth principles no more than you can apply diesel to gasoline. They just don't work the same way. There are similarities for sure. E is easy to get along with, just have to adjust the mindset. It's hard to when we have all been playing with gas and meth for so long.
The science is more than I can explain here or even in person probably. I'm a mechanical engineer by trade, Mark is a Fluid Dynamics Engineer. Mark could tell ya better than me. Call him...He's not shy.


I'd bet ya a donut Mark will tell ya he knows what MSD says, and they may not be wrong, but he knows what works and what doesn't by history and trail and error of countless hours of testing. I've been using the HVC2 on a 6AL for 15 years. Same box, Same coil. Literally 1000's of racers have too. Works just fine.

I'm just a local guy though, maybe the elites no something I don't.

[Mopar DLM]

Put a collector extension on the header and see if your AFR readings are still the same. If the sensor is too close to the end of the header it will get false readings. Also agree if the ignition is not strong enough it won't burn all the fuel and give rich readings from raw unburnt fuel going out the exhaust especially at higher RPM when it has less time to burn it

[billetbirdcage]

This may go along the lines to back up some of lizardracings info:

The improvement I think we saw on both motors (wasn't scientific by any means) when I swapped boxes also included the coil change to the HVC2 coil.

You said analog 6 box so I'm assuming your right and it's an old box since they don't make them anymore. I assume you know the digital boxes are bad about retarding timing as much as 1 degree per 1000 RPM, so if you have a digital box with a locked dizzy and set timing at low RPM you may be several degrees short at 8500. I hate the digital boxes

On the crates with E85 we did use the 7 plug. A crate is really all the experience I have with carb'ed E85


1-11/16 plate 1-3/8 ventures. Not sure how big a motor this is, but that's reasonably small for something decent size and lots of RPM, shrugs. IIRC a 1.400 x 1 11/16th is considered a 750, typically guys will use a 1.450 on something 400CID in the low 8K range.

[Jking24]

This may go along the lines to back up some of lizardracings info:The improvement I think we saw on both motors (wasn't scientific by any means) when I swapped boxes also included the coil change to the HVC2 coil.You said analog 6 box so I'm assuming your right and it's an old box since they don't make them anymore. I assume you know the digital boxes are bad about retarding timing as much as 1 degree per 1000 RPM, so if you have a digital box with a locked dizzy and set timing at low RPM you may be several degrees short at 8500. I hate the digital boxesOn the crates with E85 we did use the 7 plug. A crate is really all the experience I have with carb'ed E851-11/16 plate 1-3/8 ventures. Not sure how big a motor this is, but that's reasonably small for something decent size and lots of RPM, shrugs. IIRC a 1.400 x 1 11/16th is considered a 750, typically guys will use a 1.450 on something 400CID in the low 8K range.

I have to double check the venturi size I may be miss remembering that. Carb guy calls it a 780. And yes I have old 6al analog boxes. I have like 4 of them and they've never give me a problem. I've seen so much problems with the digital stuff and the newer stuff in general that I'm scared to change. I have no doubt that the hvc2 will work fine. I just bought what was recommended because I had no one advising me either way. My engine guy does not mess with e85 or meth so he had no objections to any of my components. I actually have a bigger carb from the same guy but it hasn't been on the car yet.

[Jking24]

Put a collector extension on the header and see if your AFR readings are still the same. If the sensor is too close to the end of the header it will get false readings. Also agree if the ignition is not strong enough it won't burn all the fuel and give rich readings from raw unburnt fuel going out the exhaust especially at higher RPM when it has less time to burn it

My o2 is in a 12 inch extension. We've also verified its not getting any reversion by attaching a even longer extension. I'm fairly confident I don't have any issues on the instrumentation side of things.