R32 Gtr Build In Usa

[jmknights93]

Just spent a couple hours reading over the whole thread. Loving the updates!

[HarrisRacing]

Fuel pressure dropping on top end. Looks like I have maxed the DW 300 pump. Time to add another pump to my setup (dang). I also found out why everyone adds a fuel sump to these cars as well. Right hand turns at 1/2 tank or less suck even at low rpms and speeds...total starvation there.

Already time for upgrade . Time to see if I have any fuel pumps laying around.

[sneakey pete]

If you don't ever plan on going with ethanol just throw in an walbro 460 and that should be more than enough. people manage to make 400kw with one and stock lines on ethanol, so if you are using 30% less fuel 500kw should be possible

That being said.... Still shouldn't have fuel starvation at half a tank, so it may pay to check your pump setup and that something else isn't dropping or constricting it when you're throwing the walbro in it

[HarrisRacing]

Will do. Thanks. I wired in a relay to the pump today (lol didn't do that yet) so we will see what happens there.

But yes starvation under right handers less than half tank.

[HarrisRacing]

Wow...

I'm embarrassed to say this but I feel like I should be clear to keep clarity with my build etc.

1) Don't EVER think the factory fuel voltage to the FPCM is going to keep up with ANY kind of uprated fuel pump. I have no idea why I didn't just hardwire a new relay in to start with, but I'm ashamed to say how much difference there was in flow. My car steadily dropped from 5500 rpms up (yes that low). No wonder why I thought I was running out of injectors. The drop was linear so I had actually tuned around it (not knowing), but at 6k it was 9.8 psi LOWER than it should have been and -20 psi lower at 7500!!! Even after rewire the pump is done at 7500 and is dropping 4.5 psi there and 8.3 psi at 7750. Some of this could just be the fact that I'm using the factory lines and some -6AN fittings at the ends. Perhaps running a straight -6AN to the rail would help...but I need to install a sump anyway.

EDIT - I am going to be testing more of this pump. I think my main feed from it was slightly kinked. I bet it will make 500 whp on pump no problem now.

2) Don't trust published fuel pump numbers. These are absolute limitations taking into account NO friction losses, etc. My DW300 pump is falling off after 7,500 rpms even after the rewire...again it could be from friction losses. I bet it's capable at the RAGGED EDGE of supporting 500 whp. It will be a lift pump from here on out and going to a sump with a real pump (walbro 460).

3) Be careful how you setup your Haltech engine protection. I had mine setup to let me know if I had seen 12.2 AFR (or leaner) after 10 psi boost. This way it's only limiting me from leaning out on top. It did NOT, however, catch the fuel pump issue! Meaning I was running 93% injector duty cycle due to the lower fuel pressure and still not touching 12.2 AFR. Since the rewire AFR's went to the 10's AFTER removing 15% out of the fuel map! I will now also have the fuel pressure set in my engine protection to give me advanced notice that I dropped fuel pressure below my target.

[sneakey pete]

That's a lot closer to what I would have expected to see from one of those pumps.

I'd strongly suggest doing a walrbo in tank if you're not going E85 and just keeping the tank above 1/3rd for all hard cornering activities. A little inconvenient sure, but its way cheaper, less stuff in the boot and way less noise than the external bosche options people do

[HarrisRacing]

Yeah my brother has the two 044 on his turbo Mustang and damn you can't hear yourself think in that thing.

I did just get in the tank and found the cap had popped off the end of the factory fuel "sump". So there is my starvation issue for sure since the cap keeps the fuel from just rushing to the left. I put an industrial zip tie around it to hold it on (hey, they work).
Also reset my fuel pump angle in the cradle to give a better angle on the fuel feed lines (perhaps some kinking going on here?).

I will do the boost a pump before going sump at this point because I feel the car will likely top only 520 or so whp on pump.

Yes one walbro 460 would be perfect.

[Meathead]

Hi Patrick,

Quick question about EFR blow off valve.

Did you tee into the vacuum line on the carbon canister or did you run the original line around to the BOV?

Cheers

[HarrisRacing]

Removed carbon cannister (where my ps pump reservoir is now) and just ran a new line from the intake manifold using the factory metal line located behind the cam gears

[Meathead]

Removed carbon cannister (where my ps pump reservoir is now) and just ran a new line from the intake manifold using the factory metal line located behind the cam gears

Thanks for that, I will keep the canister anyway but use the factory line.

[HarrisRacing]

Ok so I was tired of losing fuel supply and strange starvation at low fuel levels.

Here is my solution.

Integrated engineering sump with AEM 380LPH pump. Mounted under car and all plumbing is under car to/from factory fuel lines. I will add the check valve later and run a line to the front of the car, but I was missing a few things to do that.

So far ZERO fuel issues. I actually changed the fuel map after resetting the regulator and it started coming in nicely. This is a much better pump choice than what I had IMO.

Also added about 5 deg timing so far and the car is just waking up! I'll try to get back on the dyno soon enough.

[Ben C34]

Thos tanks look nice but really are too small. If at full noise the lift pump starves that tank will empty in a second.

[sneakey pete]

Easy enough to make it bigger.

I'd toyed with the idea of a setup like that myself for quite a while but in the end a better intank solution came up so i'm going to go with that.
Weld an extension on it (plenty of space!) and she'll be apples for pretty much anything you can throw at it on 98 i'd think.

[HarrisRacing]

Thos tanks look nice but really are too small. If at full noise the lift pump starves that tank will empty in a second.

I thought that too at first...And yes I wish it was about double the size but if does have let's say 5 seconds of 100% fuel supply by itself with the assumption of 100% injector fuel usage.

The pump can't access the very bottom of the tank so you lose about 15% available fuel there. The pump uses about 25% of the total volume as well so really you're left with about 1 liter. Assuming no return from the rail with a 380lph pump you end up draining at a rate of .101 liters per second...giving me about 10 seconds before my listed safety factors. Engineering factor says 5 seconds should be solid.

Sneaky, make sure you are lifting in the tank somehow...any air sent up front was totally detrimental to my setup.

[HarrisRacing]

My brother and I took a road trip for the Hot Rod Power Tour and entered the car in the autox event at the Circuit of The Americas in Austin Texas. You'd never believe we took Fastest time of the day with only 2 runs! Yeah....that happened.

https://www.youtube.com/watch?v=j5CSFrnP_GU

Thanks to the Dose Pipe we were able clench the victory!

[jmknights93]

Well done. That video looked intense!!

[Scooby]

Thanks to the Dose Pipe we were able clench the victory!

Well done!

(Please tell me you mean clinch? )

Edited June 14, 2016 by Scooby

[SimonR32]

If you pull the gearstick directly down you will select 2nd

[HarrisRacing]

I did at the very end when I actually could use it.

[HarrisRacing]

Ran across this street on some backwoods of texas.