Drag Race issue

made a couple passes in my truck last night. TRD supercharged and recently went with Prospeed fuel kit and HP tuners. First full 1/4 mile runs since then. Both times it cut out at the top of 3rd gear. See video below. Any idea what could cause this or what to do about it?


https://youtu.be/F2XvANlq5Es

 

Hope it’s not a fueling issue since I just went full stupid with fuel upgrades. Was in “D” for one run and sport shift for the other. Wouldn’t go in to 4th in either scenario. Wasn’t watching tach, but redline was moved up to 6300 with the tune

 

I would think that fuel would be the logical thing to look at first. I don't know if you have the ability to monitor fuel pressure. You may not be up to this point yet, but it doesn't hurt to check. @ViktorG has a video of his solution at his particular modification level at that stage. I don't know where (RPM) he was encountering issues, but he may be able to get you looking in the right direction...

 

What fuel pump are you running ?

 

TI auto 450 which is the same as a walbro 450 I believe

 

Good question. I’ll have to get creative with that since the gauge is under the hood

 

You have HP Tuners, need to data log what is going on first imo.. I can look through your tune file for anything obvious if you want.

 

Update: I went and made a pass with my camera under the hood and got the same result. Definitely an see the fuel pressure drop off when the issue arises. Big question is whether the fuel pump is jacked up or is the computer sending a signal to cut??
https://youtu.be/F2XvANlq5Es

 

I am hp tuned, but have no idea how to mess with any of this stuff as I didn’t do it. Is there anything I can send you to see, let me know.

 

How much fuel is in the tank? If it is anything less than 1/2, you will run into major problems due to the fuel sloshing back in the tank on acceleration and the fuel pump basket being sucked dry by the pump.
The fuel pump module will never cut your fuel pump off unless your engine stops running.

 

Makes sense. Was at 1/4 tank at the track and less when I made the under hood pass earlier. I’ll fill it up and check later.
Curious as to what the failsafe is when the truck shuts down due to loss of traction or other events where the truck falls on its face?? Surely the ecu is cutting something

 

In the case of traction control engagement or maximum speed limit being reached the ECM closes the throttle.
Your issue is definitely from running extremely lean due to the low fuel level. Don’t launch it with less than half a tank or you may very soon be looking at one of your rods sticking out the side of the block.
I’m guessing you went and dished out a bunch of money on the Prospeed system? Unfortunately they don’t address the main problem of the location and setup of the fuel pump/basket and instead sell people their fuel rails, which are completely unnecessary since the stock rails can easily flow 1000 hp worth of fuel.

 

The devil is in the details...

 

So what should someone do instead, victor?

 

I posted a video of the surge tank that he installed...

 

The truck is black, a common problem with black trucks is they outrun their fuel supply.

 

One could do a number of different things to remedy this:
Custom oversized fuel pump basket
Relocate the pump to the rear of the tank without the stock basket
Install an external fuel pump that has a pickup at the rear of the tank
Install an aftermarket syphon system that will keep the basket full even when demand for fuel is high
Build a surge tank setup
Replace the factory tank with a fuel cell

 

You forgot "Pay Victor an obscene amount of money for his truck"

 

I don't know...he seems to be having a lot of fun with his build as well as having a lot of time and effort invested. But he may still be interested in "obscene".

 

You would be correct that I am running the Prospeed kit. They were the first in Houston to do proper tunes on our platform and also one of very few small shops that actually do any real investment in trying to get some innovative solutions out there. When I contacted them to tune my truck, they had done a few at that point and recommended I wait since they were running in to lean conditions and were developing a system to support.
It does stink that the fuel tank is another source of issue that was not part of this “comprehensive” kit. I don’t have any regrets about buying Prospeed kit and am happy to support shops that support our hobby.
That said, I am going to take as a lesson learned and make sure I have sufficient fuel next time. I had not really considered that before I ran. I was just thinking it was nice to not have an extra 100# of fuel to lug down the track.
In the future I will consider making additional upgrades as I would like to see this truck in the low 12’s or even 11’s someday.
I also wanted to say thanks to you man for doing some cool things and sharing your knowledge with us.

 

I am happy to share my knowledge and real life experience in modifying these trucks.
In the coming months, I will be removing the entire stock fuel system from the Tundra and testing all of its components to show what the actual flow limitation of it are.
I certainly don't want you to regret buying their kit, it is in no way detrimental to the operation of your truck.
I just wish they were honest with people and not spreading misinformation aimed at increasing their sales while not addressing the real concerns with fuel delivery on this platform.

Regarding drag racing, I am excited to see you are getting into it with the truck.
11's are certainly possible with a few supporting modifications.
With your current 1/8th mile time, you will be hitting around a 12.7 in the quarter once you fill up the tank
What is your current truck setup as far as mods, tires etc?
Cheers!

 

Current mods are TRD S/C w/URD pulley, ARH Long Tubes/Mids, 3" X-pipe and Kooks 3in-out adapted to TRD tailpipes, level 10 Trans, auburn rear, Prospeed fuel system, and HP dyno tuned. Boost gauge is only showing about 7-8 psi.
Truck has 185k and 125k on the S/C.
Stock Suspension w/ homebrew caltracs in the back.
Stock Tires
Truck is 4wd so that is typically how i launch or its just a smoke show.

 

Give Keith Carty a call at 760-877-4234. He races his 2013 Tundra and can probably help you with a few things to improve on.

Thanks, Shawna, DDI