RB25 Haltech and Fuel System Upgrades

[RRRRB]

post that graph!!

[RRRRB]

Yo, lets see that graph bud!

[Darius]

Here ya go! Sorry this took so long for me to post. You can see the boost PID still needs some tweaking to keep it from hunting so much.

[RRRRB]

Anything new with this car?

[Darius]

Nope not really Just ordered new tires and am trying out a new starter. I haven't had a chance to install it yet. It is for sale because I need cash for home improvements

[RRRRB]

you need to take it out to the track before you sell it!!

[julio]

Nope not really Just ordered new tires and am trying out a new starter. I haven't had a chance to install it yet. It is for sale because I need cash for home improvements

How much?

[Darius]

Nope not really Just ordered new tires and am trying out a new starter. I haven't had a chance to install it yet. It is for sale because I need cash for home improvements

How much?

$20k...It irks me that I had to dump another $1,200 in tires into it just to sell it, but the current ones are spent. Price just went up to $21,200 hahahaha

[RRRRB]

How do you have the fuel lab pump setup? Will it draw from the tank externally? How noisey is it?

[Darius]

I have it mounted in the trunk with lines bulkheaded through the stock fuel tank cover. The pump suction is a -10AN with Fuelab stainless steel pickup sock. If I could do it again, I would have removed the stock tank, sold it, and replaced it with a good sized fuel cell so I could mount the pump under the car and -AN lines were easier to plumb up. The pump is noisy, but no more than any other high capacity external pump. In fact, it is probably slightly less noisy than most.

The pump is controlled by Haltech to run at 50% speed below a certain TPS position or below a certain rpm threshold before it steps up to 100%.

[RRRRB]

Why couldn't you mount it under the car now?

[Darius]

I could, but I was originally trying to keep the pump in the trunk to keep the suction line as short as possible.

[RRRRB]

Is that a big deal with that pump?

which pump are you running and what base fuel pressure are you set at?

Im thinking about making my fuel setup simpler, im using twin bosch 044's in a surge tank with a intank walbro feeding the surge tank.

i need enough pump for 800whp on E85 and have to run a 55psi base to make my injectors flow enough as well..

[Darius]

Is that a big deal with that pump?

which pump are you running and what base fuel pressure are you set at?

Im thinking about making my fuel setup simpler, im using twin bosch 044's in a surge tank with a intank walbro feeding the surge tank.

i need enough pump for 800whp on E85 and have to run a 55psi base to make my injectors flow enough as well..

Yes, pumps do not do well with restrictive suction or a suction lift where it has to draw liquid up to a higher elevation before getting to the pump. But once at the pump, it can "push" 10X better. Another problem with a restrictive suction line is it can cause the fluid to cavitate or "boil" ahead of the pump. Once that gas pocket hits the impeller, it turns back into a liquid rapidly. This violent transition will eventually destroy any pump from a little fuel pump to a massive industrial pump.

A good rule of thumb is that you want to keep the velocity in the tubing less than 10 ft/second. Fuel has roughly the same viscosity as water, so you can use basic hydraulic calculations to calculate losses. I realize this is more engineering than hobby talk, but velocity (V) is flow (Q) divided by cross-sectional area (A) of the tubing. V=Q/A

That fuel setup is tried and true, so it shouldn't be an issue. You'll have to look at how much fuel you need to make that power and what psi of boost you will be running. So say you need 8900 cc/min to make 850hp at the crank and 35 psi. If your base fuel pressure is 55 psi, the pumps need to be able to deliver the fuel at 55+35 = 90 psi to overcome the intake pressure. So, the design point is 8900 cc/min=8.9 L/min=534 lph at 90 psi. Running two pumps in parallel cuts the flow in half, so 267 lph at 90 psi per pump. If the pump can't deliver that pressure, you need a different pump with higher pressure rating. I didn't want to rely on two fuel pumps so I went with a single 41402 Fuelab pump. Pumps have drastically improved over the past 5 years so I'd look at in-tank options if they can meet your needs. That way you don't have to change up plumbing as much.

[chad b.]

What turbo setup is on this car again?

[Darius]

Garrett T04Z with .84 T4 divided exhaust housing

http://www.atpturbo.com/mm5/merchant.mv ... gory_Code=

[mixeds14]

Matt, I always admire the cleanes of ur car and how u go about doin things, glad u ain't sold the car yet, maybe u just need to keep it..

[Darius]

Matt, I always admire the cleanes of ur car and how u go about doin things, glad u ain't sold the car yet, maybe u just need to keep it..

HA! I actually sold it about a week ago after I got it running on a new CAS module and AEM 24+1 slot trigger disc. The new owner is awesome and is going to do all the things that I have had on my bucket list for the past 5 years like re-do the front seat upholstery, tint the windows, install a decent sound system, fix the door dings, and respray the front bumper. I am excited to see it road ready next spring. It should look better than ever!

Now I, on the other hand, am stuck with a 128 year old house and fixing about $50k worth of <ahem> handiwork....I'll keep the culturally biased comments to myself I'm just glad it didn't go to some dumba$$ kid who would either "drift" it into a light pole in the HS parking lot or kill himself and others street racing it. Win-win, I'd say! I'll build something new and different some day. Give me about 4 years to plan it and move out of Chicago though.