E85Forum.com

seanmathes · Joined: 29 Apr 2009 Posts: 20

I am trying to finish up my E85 conversion on my twin turbo GT and need some help. I have been trying to get help over on turboforums but haven't really gotten what I am looking for. Here is the short version of the story behind the car. When on gas this car was approaching 1000 RWHP according to the dyno sheets. Yes I did personally see the dyno sheets but did not actually witness the dynos as it was before I had the car. I bought the car several months ago and wanted to convert to E85.

I have changed the injectors from 60lb siemens deka to the high impedance Ford racing 80 lb injectors. The car is now tuned and was dynod again yesterday. We weren't able to go above 15psi as the car really started to lean out under boost. We weren't sure exactly what was going on and tried adding more fuel to the tune but still stayed lean. So we are pretty sure that the pump is not supplying enough fuel. I watched the fuel pressure gauge during the pull and it would build to about 60 psi and completely drop off back to about 50 as boost increased (thus the reason for the lean condtion).

So now I am thinking I definitely need a larger pump. I am planning on going with the Magnafuel PRO Tuner 750. I am currently running a full aeromotive fuel system with an A1000.

Can anyone give me any input on my setup and tell me if they think this is the best way to go?

On the dyno we hit 775 RWHP at 15.6 PSI and we were too lean so backed it way off.

I want to run this car at a minimum of 20 psi and maybe go as high as 30 psi. Thanks for any advice.

Sean

PS. Here is the thread on turboforums if anyone would like more info about the car.

http://www.theturboforums.com/smf/index.php?topic=126321.0

Turbo98 · Joined: 03 May 2007 Posts: 100 Location: Misouri

I didn't read the rhread yet over on Turbomustangs but you could be running out of injector. What was the injector duty cycle? According to some quick calculations, it appears that could easily be the case. The blend of E85 could slightly affect this also. Are you running an auto too? That would sap even more power.

Turbo98 · Joined: 03 May 2007 Posts: 100 Location: Misouri

Ok. I read through all the stuff on your thread over there. I'm sure you will need to upgrade the pump and injectors. They are both probably maxed out.

seanmathes · Joined: 29 Apr 2009 Posts: 20

Yea I think you are right. I just datalogged on Saturday and finally plugged in the numbers for the dutycycle and they are totally maxed out at 15psi. Really really frustrating as my tuner though we would be ok with the 80s. So do you think the 120s will definitely be big enough even if I got high 20s boost? thanks for your help.

Sean

Turbo98 · Joined: 03 May 2007 Posts: 100 Location: Misouri

Ok. A couple things. The amount of boost really doesn't matter with regard to the injectors as much as it does the fuel pump. It will affect injector size if you are trying to stretch the injectors by increasing the base fuel pressure for more injector flow. This is because whatever boost pressure you run, you have to add this to the base pressure to come up with the total amount of fuel pressure under boost. So if you have to run your base pressure at 55 PSI for example in order to get more flow out of your injectors, and you are runnning 30 PSI of boost, your fuel pressure will be around 85 PSI under boost. This is important because as the fuel pressure goes up, pump flow goes down. So, you need to size your pump based on the FP you determine you will be running. Most pump manufacturers have a flow chart available at different pressures so you can see. I can tell you that the A1000 is not enough for your car. I've looked at their flow chart before and it just doesn't do too well under higher pressures.

How much power are you looking to make? This will determine your injector size. Not so much the amount of boost.

Now.... I noticed something on your 713rwhp dyno sheet. It said "SAE 1.23" at the bottom. You're in Denver so I am assuming this is a huge correction factor applied to these numbers. So, if you take out the correction factor, the car is making 580rwhp at the dyno at your location. This is important because this is the amount of fuel you're using to make the power BEFORE any correction factor is applied. So if you are looking to make a CORRECTED dyno number of 1000rwhp, you can do so with smaller injectors than if you didn't have the correction factor. You may just do it with the 120# injectors according to what I can tell. It will be close if the base FP is 43 PSI (the FP in which the injectors are rated at). But I don't think you will make an uncorrected 1000rwhp with the 120's at the rated 43 PSI base FP. If you increase the base pressure to 55 PSI though, you can stretch them to flow another 12%. This would probably get you to the 1000rwhp mark CORRECTED.

Hope all that makes sense. Sorry for the long post.

hotrod · Joined: 19 Apr 2005 Posts: 872 Location: Colorado

seanmathes · Joined: 29 Apr 2009 Posts: 20

Thanks guys that was really great and way more than I have gotten so far over at turbo forums. So I am planning on going with the magnafuel protuner 750 unless you guys think that is overkill. I talked to the guy at Magnafuel and he seemed to think it would be appropriate but warned me of the possibility of needing a fuel cooler to avoid vapor lock. I might as well go bigger as the 4301 is not that much cheaper.

Honestly I really don't know what power I am trying to make. I have this motor that was putting out approximately 1000 HP at 30psi of boost when it was originally built in Texas. That is the only thing that I have to go off of. My plan is to try to run it at a minimum of 20 psi for now. On saturday on the dyno it put down 775 RWHP at 15.6 psi so I don't think a couple hundred more is out of the question. My next step is definitely upgrading the pump and then will see where I'm at with the injectors and may try them at a higher rail pressure. Thanks again and I look forward to hearing more input.

Sean

Turbo98 · Joined: 03 May 2007 Posts: 100 Location: Misouri

Turbo98 · Joined: 03 May 2007 Posts: 100 Location: Misouri

Post the specs on that fuel pump your looking at (flow at different pressures) and we can see how it will perform.

Tech @ BG · Joined: 08 Nov 2007 Posts: 12

If you are boost referencing the regulator keep in mind with your fuel pump that you will need to have one that makes more fuel pressure then your base plus your boost. For example if you are running your base fuel pressure at 50 psi and trying to run 15 lbs of boost your fuel presure requirement would be the 50 + 15 for 65 total. For the horsepower range you are looking to be in and the amount of boost you might get to you will probably need to look at a much higher end pump then what you are currently looking at or even going into a belt driven application.
_________________
Technical Support
Barry Grant Inc.

Tech @ BG · Joined: 08 Nov 2007 Posts: 12

Also keep in mind that as the pressure increases the volume will decrease.
_________________
Technical Support
Barry Grant Inc.

hotrod · Joined: 19 Apr 2005 Posts: 872 Location: Colorado

Turbo98 · Joined: 03 May 2007 Posts: 100 Location: Misouri

I glanced at Magnafuel's web site and couldn't find any flow data. I would have them e-mail you a chart with flows at different pressures. To make a blanket statement that they will support 2000HP doesn't mean much. Take into consideration that you are running E85 and require higher pump pressures due to boost, we need to see the flow rates. Foe example, they say it can support UP TO 2000HP. That's flywheel to start. So take off 300HP right off the bat. Assume worse case that it takes 40% more flow of the E85 to make your power. That puts it down to around 1200rwhp. That's at 40 PSI. So say you are running a base pressure of 50 PSI and 30 PSI boost, that's 80 PSI pump pressure required. Who knows how much it will flow at that pressure but one thing is for sure--that's double the pressure. So you could be down to borderline 1000rwhp. Plus it doesn't say they are compatible with any alcohols. I'm sure at this point you want to be sure and only want to buy one more pump!

hotrod · Joined: 19 Apr 2005 Posts: 872 Location: Colorado

Also remember fuel pump flow varies with both pressure and supply voltage, good large gauge wiring to the fuel pumps is a very good idea. Ask them for flow charts at supply voltages (typically 13.8 v). Measure the voltage at the pump under full load to make sure you have enough juice to drive the pumps at full rated output.

On high power setups some folks even use a voltage stabilizer module that guarantees the pump see 14.2 Volts or what ever their ideal voltage supply is. It makes the pump run cooler and last longer too.

Larry

seanmathes · Joined: 29 Apr 2009 Posts: 20

Can you say trying to drink from a firehose Smile

I will need a bit to digest all of this. First thing in the morning I will try to get flow specs. I can't thank you guys enough you have been great.