dmhenderson's Nismo '12 GTM supercharged build thread where I freak out a lot

[theDreamer]

Well once you have the e85 tune, unless someone jumps on here tomorrow, you will be the first known e85 SC.

[ModBargains]

Meanest headlights ever!

[dmhenderson]

Cliff Kim at Daedalus Customs is responsible for the headlights. I love them too.

[future370zzz]

Where did you hear that the aeromotive pumps have corrosion issues with e85? Interested because I'm on the fence with e85 and have an aeromotive pump installed.

[dmhenderson]

Originally Posted by future370zzz

Where did you hear that the aeromotive pumps have corrosion issues with e85? Interested because I'm on the fence with e85 and have an aeromotive pump installed.

Frank Hill (Hill's Garage). Was initially the pump we were going to go with but said he did a little digging and they have problems especially with E85.

As far as I'm concerned, Frank is the word of the almighty when it comes to these cars so I'm gonna go with whatever he recommends.

[dmhenderson]

So the car is at Hill's still. I dropped it off a little earlier than they would have liked but I was concerned about the oil leak. In the meantime, I spent Friday afternoon was slow so I spent my time polling local E85 stations to figure out which ones don't change up their E85 mix at all.

Found 2 less than 5 minutes from my house, bought 3 five gallon canisters at Home Depot and filled them up today. Should be enough to tune the car and get it home afterward.

[dmhenderson]

Fun with E85 conversions:

Originally Posted by Frank

We are having a couple of issues tuning the car. First we have abnormally high fuel pressure. We should have approx 50 psi and we have 70 psi.I suspect the new higher flowing pump is overwelming the factory pressure regulator and siphon plumbing driving the pressure up. The problem comes in when you get enough load on the fuel system the volume drops enough to let the regulator take over and hold pressure at 50 psi. The 20psi fuel pressure drop off is tough to tune a fuel map around. Its kind of like hitting a moving target. You chase your tail around, one minute its rich next its lean with no user input. I need to figure out what I need to do to get the pressure stabilized at 50 psi.

We also were getting air fuel ratios that would shift from one pull to the next. I have a G37 with stage 2 kit at the shop doing similar things with erratic a/f ratios and we found the bypass valve sticking. We have not performed the repair to confirm yet but I did verify the valve was not fully shutting at times causing large boost leak.
unfortunately yours is not so easy to get to to check in its current location behind bumper. I may need to check this if stabilizing the fuel pressure does not solve the erratic a/f ratios.

The saga continues. Wu-tang.

[mikey1600]

Hey mate, theDreamer sent me here haha.

just installed the Stillen kit myself and had it tuned on Monday, I'll be watching your thread closely as I was wanting to pull the trigger sometime on E85 as well

all the best hope it all works out well!

[dmhenderson]

Word of advice on the E85 thing:

Don't.

So quick update:
-Synapse Engineering (owned by Porsche lol) BPV being welded on today.
After a meeting of the minds between Frank, the guys at CJ Motorsports and the guys at Z1 Motorsports, they determined the entire factory fuel system had to go.

-CJ Motorsports stage 1 fuel return system being installed tomorrow.

-Afterwards, we all collectively hold our breath when it goes on the dyno.

Here's a bonus shot of the (semi functional) car in question this past weekend at Hill's charity show:

[dmhenderson]

Update on the valve. The correct P# is DV001A.006

[theDreamer]

So any final word on why the need to go full return system? Seems like the TT guys are able to bump power with just a larger fuel pump & injectors (with e85) and be fine, curious why the SC is not liking it.

[dmhenderson]

I am running 1000cc injectors instead of 600-800cc which may be the issue. No other explanation for the fuel pressure being so high.

[dmhenderson]

Some clarification and a non-update:

-The reason my fuel pressure is so high is because I'm trying to tune 93 octane on 1000cc injectors/340lph fuel pump. If I were to *only* run E85, I'd be fine but since I'm insisting on a backup pump gas tune (because knowing me, I will run out of gas at some point), we're having to install the return system.

-Hill's called yesterday and let me know that they now have the Synapse BPV with the correct bung. Assuming it'll be off to the welder today and on the dyno tomorrow/Fri.
(Isn't this fun???)

[dmhenderson]

Painfully slow status update:

Got word yesterday that the new fuel system is in, the new BPV has been welded on and the car is almost dyno-ready.

Could the end be in sight? So much like Charlie Brown, I'm going to get excited to run and kick the football again...

[FPenvy]

Originally Posted by dmhenderson

Painfully slow status update:

Got word yesterday that the new fuel system is in, the new BPV has been welded on and the car is almost dyno-ready.

Could the end be in sight? So much like Charlie Brown, I'm going to get excited to run and kick the football again...

then GTM pulls the football away and laughs? lol