Jackass w/ LS9: original build and new Jackass 2.0 updates!

[will69camaro]

Originally Posted by mikels

We've had no issues running returnless fuel systems - even with big power / high flow - when you stage secondary pump to come in early enough to maintain stable control as fuel flow rates rise.

In Brian Thomson's Corvette, we have basically the same engine as JA2.0, but are running dual TI 267 pumps with staged Vaporworx PWM controlled system. Same E85 - same flow rate requirements. So far, has performed perfectly with no pressure falloff - although we have not yet tracked the car (coming soon!).

On both cars I integrated the flex fuel sensor to allow seemless transition between pump premium, E85 and everywhere in between. Mark even has the ECM measured ethanol percentage displayed on his dash. Yes, there is variation in ethanol %, but system accommodates all levels without issue.

Like Carl says - big power & high flow rates mean no easy solution - but we will get there!

Carl had been great to work with as development continues on Jackass 2.0 and TA Corvette systems. Having a system that will meet WOT E85 fueling requirements while delivering stable flow rates on gas @ idle WITHOUT fuel heating issues is an incredible demand. All this would not be possible without his support.

Primary reason went to E85 was not for power, but for cooling. Power gains are just side benefit (6-8% is what we measured).

I think we have reached a practical limit for the Thomson Automotive 7.0L SC package. We've passed point of diminished returns as far as lap time reduction (will still help in 1/4 mile and standing mile events). However, as Mark can also attest - being traction limited to ~80-100 MPH is something you'll never tire of!

Dave

Carl has been excellent in my dealings with him so far as well. We discussed two CTS-V versus three when I had ordered. As plans always seem to change and the project snowballed even further, I'm going to be pushing the two more than I had originally intended.

I am very aware of the benefits on the sensor, and sadly holley has not made a compatible sensor available yet on their standalone engine management systems, but I am told they are working on it. 6-8% when you're talking 1000+rwhp cars adds up however. I'm hoping to make north of 1000rwhp on pump 93, so the benefit of E-85 with cooling as well as the benefit of resistance to pre-detonation, I'm hoping we can add timing and see more than just the 6-8% gain. I'll find out more when I get to testing and maybe by then holley will have their system of ethanol content working by then!

Looking forward to traction at 100mph issues!

William

[mikels]

Originally Posted by will69camaro

I'm hoping we can add timing and see more than just the 6-8% gain.

We are adjusting timing based on ethanol % and 6-8% is typical. I've never seen E85 gain more than that without additional airflow (in this case would be boost).

Did find higher percentages of ethanol (up to 85%) to be very knock resistant - when trying to hook the spark curve on dyno, would reach point where additional timing made no more power - but still did not generate knock. On pump gas typically start running into knock issues simultaneously with power gains flattening out - if not before (this on high cylinder pressure engine).

You are correct though that while 6-8% may not sound like much, when added to numbers in the mid 900's, it's quite a bit!

All numbers I quote are engine dyno as well - 1000 RWHP is a staggering number - and nearly impossible to achieve while maintaining the driveability level we have with this package.

Dave

[will69camaro]

Originally Posted by mikels

All numbers I quote are engine dyno as well - 1000 RWHP is a staggering number - and nearly impossible to achieve while maintaining the driveability level we have with this package.

Dave

Yea I dont suspect it will have the driveability as that package, but should be ok. Nice thing about turbos vs blowers is I can be more selective of when it makes big power.

I fully suspect that 1000rwhp will be in the neighborhood of 20psi, but time will tell.

William

[CarlC]

Thanks for the compliments William.

Originally Posted by will69camaro

......holley has not made a compatible sensor available yet on their standalone engine management systems.....

If anyone is running a Holley Dominator ECU using a VaporWorx controller purchased prior to November 2014, please send the controller back for modification. There is something in the Holley trigger that causes VW controller damage after a short time. It will simply stop working. There does not appear to be any problem with the HP systems.