With Hard Drag Launch Then Falls On Its Face????

DART505

DART505

WFO ALL THE TIME
Joined
Jun 1, 2006
Messages
1,198
On my 05 4x4 at the drag strip when I spool it tight and launch hard 1.69 60' goes 200 to 300' and goes down to idle no matter what pedal position and rp still shows 24k pressure on CTS later at 1000' it will wake up again. Turn tune way down and leave low boost 10psi or so it will run 12.70s?? Acts like starving for fuel but tank has sump and 220gph fass with 1/2"hose from pump to each cp3.
Using new SSR tuner 300hp injectors Gorend full billet trans 33x13.50 street radials:blahblah1:
WTF????
 
What settings on SSR do you have "Shift Limiter" programmed at?
 
What version of SSR, and what are all of your settings?

Paul
 
I'll look,I changed it so much trying to fight the problem. I started very close to your tune and tweeked it.
On the way home that night I stopped 2 times and did hard launches and ran like a bat out of hell!
 
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Bruce Block (B&B Tooling)was having these same issues at the first Florida super stock race. If I remember correctly it ended up being his fan clutch going out. Replaced it and no hard launch cutout issues. Maybe shoot a pm to him and confirm it was the fan clutch.

Chris.
 
Freezingsystems said:
Bruce Block (B&B Tooling)was having these same issues at the first Florida super stock race. If I remember correctly it ended up being his fan clutch going out. Replaced it and no hard launch cutout issues. Maybe shoot a pm to him and confirm it was the fan clutch.

Chris.
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Will do just to check. That is weard but anything possible.

Ok version 4.05 17A
T stock
LLT26
HLT32
LLR18
HLR22
LLD11
HLD30
No that is what I have burned in there now but had others before but found no or very little boost launch was the only way to get a full pass.
Thanks
ChrisP
 
The clutch fan would totaly shut the truck off but wouldn't leave any visible codes. I would still have to clear the codes with the smarty and the thing would start right back up. I don't think that is what your problem is though. I think you are starving for fuel somewhere. My guess would be either you are blowing the HPRV or you have a filter or line plugged somewhere. A couple of years ago I was changing out relief valves and got a bad one and I would launch the truck and it would completely fall on its face and then the thing would seal up again and gradually take off but it was a pretty drastic thing when it happened. You could drive the truck as long as you didn't try and hit it hard with a lot of pressure
 
Drastic is what it is,I am getting ready to hook up my LP fuel gauge to see if it is a feed issue.The FASS 220 pump is new but the only place I could mount it was pretty high against the bottom of the bed but I had 1/2+ tank of fuel at the time.The nipple on the tank sump is facing the front of the truck and dont see where it would make a differense?My popoff is new 32k and shows to be holding good pressure according to the CTS gauge.Could it be draining the stock rail,a extrude one is next on the list. It seems if that was the issue it would start missing?
 
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If you have another relief valve I would try it. I am almost certain. that is the problem. The other thing you might want to try is to lower the rail pressure. Making power is not so much having high pressure but more maintaining it. So if you back it off some so it wont blow the valve but still maintain 24000 or so. I run a stock relief valve on my truck. I guess I have been lucky so far getting away with it.
 
I went to a new valve after the other would only hold 18k after few hard passes. I tried rp at 0 at the track same problem.So you think it is dumping the rail right after you nail it. What settings are you running Bruce if you dont mind sharing? I sent my old valve back for core charge,do not have another.
 
Chris that is what it sounds like to me . I would find one that I know was good and try it just to rule that out. I don't know my settings off hand I could look this evening and let you know . I think the hlr is somewhere in the mid 20's .
 
DART505 said:
Could it be draining the stock rail,a extrude one is next on the list. It seems if that was the issue it would start missing?
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Wasting money on extrude hone fuel rail will be the same as throwing it in the wind. Who's twin cp3 setup are you running?
 
A while ago I heard of another truck that actually was lifting the solenoids off the top of the injector just enough to prevent the injector from operating, affectingly shutting the truck down.

If the RV swap doesn't work out, I'd take a look at the injectors, maybe run an oil report to see if any fuel has escaped and into the oil.
 
307diesel said:
Wasting money on extrude hone fuel rail will be the same as throwing it in the wind. Who's twin cp3 setup are you running?
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I was wondering if it was unicorn milk!
Stock 5.9 pump on top and 5.9 pump with old (5years) bag of parts in it.
Dont remember the kit name brand but the pump returns T into oe lines which is next on list of upgrades.
Can you do away with the valve or not safe??
 
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DART505 said:
Can you do away with the valve or not safe??
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You can if you are very very very careful how you release the throttle. Put one on and leave plenty of time to back off over a few seconds. Should be easy enough to figure out if you have a bad RV with a RV cap.
 
If the pumps "T" together on the rail feed line, then the feed line cannot flow the amount of fuel the the pumps are making. If you can feed the top of the rail where the relief goes with the top pump and feed the bottom of the rail with the bottom pump, you will get all the fuel that the pumps can produce to the rail. Volume is key. A relief valve is certainly a good idea. I haven't ran one in 3 years on my puller, but I am sure that I've paid for one many times over in broken injectors. This year I am switching my twin cp3 kit to a motorsports kit. It it setup really well with fuel volume in mind.
 
TCDiesel's 5 way valve works really well. they can be a pain to seal but allow for the RV and pressure sensor while feeding the rail in two spots... Complements the ATS twin kit very well.
 
JasonCzerak said:
A while ago I heard of another truck that actually was lifting the solenoids off the top of the injector just enough to prevent the injector from operating, affectingly shutting the truck down.

If the RV swap doesn't work out, I'd take a look at the injectors, maybe run an oil report to see if any fuel has escaped and into the oil.
Click to expand...

JasonCzerak said:
You can if you are very very very careful how you release the throttle. Put one on and leave plenty of time to back off over a few seconds. Should be easy enough to figure out if you have a bad RV with a RV cap.
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Stick to spending 3 weeks to install a set of twins instead of giving worthless advice!:kick:

Chris, Do you have the shift limiter set to "off"? I would also try setting the Torque to "2" mild. Have you used the POD feature? If so, try reprogramming the ECU making sure you leave the POD at 99. I always had issues when trying to go back to 99 after trying the POD. By the way, a modded rail is a waste of money. Also, try plugging the RV banjo bolt and see if it solves the problem. It's easy, just tap the inside of the bolt and put in a 1/4 npt plug. You can take it out afterwards if you want.
 
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