Fueling issues, dual cp3 belt slip, maxed out 165?
- Thread starter LSxBakakos
- Start date
I dont think that 100hp is 100hp. You gained some et from that better 60ft and you were only a tenth faster in the 1/8. Had it not sputtered, you might have only gained 2 tenths instead of 1. Mph is not overalling much more at any spot either.
I agree fully, from your previous post of not being needed as far as the sending unit it had to be replaced and i plan to make a project out of it since my OCD is fierce lol. I'll be doing the entire underside of the bed in raptor liner and if any rust is on top of the frame addressing it then and there. As far as that 100hp I do wonder if fuel has been holding me back or if the tune is "detorqued" too much. Moving forward I'll be doing some other stuff too, probably shock relocation and eventually lighter/forged wheels
Yeah i dont think I’d get hung up on the fuel. By all means change the pickup if it needs to be done though.
See what you can do for a full log next time at the track.
See what you can do for a full log next time at the track.
Will do! The only other culprit I can think of would be the valley pump being on its way out but time will tell
The log will help tell you that. We'd be able to see desired vs actual, reg current commanded vs actual, look at fuel quantity/duration and so forth.
Def log instead of guessing and loading up the parts cannon. Local buddy of mine had a problem they only showed up at Atco near the end of the track. Convinced it was fuel, and he wasted time ahd money until he found an old corroded finger stick. Once it was removed, the truck ran so well that he got pulled over doing a test hit in town. Hahaha.
As long as i can get the truck to replicate the issue that's no problem lol. And hopefully this fix is the sender or some other simple stupid ordeal.
Also bdsankey my apologies for the late reply, here's the pn for the gm sender
Attachments
As already mentioned above but I agree
The better 60’ time netted you the better ET.
I don’t feel the 100 more hp was the difference
The better 60’ time netted you the better ET.
I don’t feel the 100 more hp was the difference
I agree. Hopefully with relocating the rear shocks and going over to qa1's in the rear too(front has double adjustable)will net better 60's. Also curious to see if the fuel restriction has any effect on ET
Just figured id update you guys, 2 weeks ago I took a week off work, ripped the bed off and did the whole project. Ended up doing ss brake lines while the bed was off, new tank vent amongst a lot of other odds and ends. Shot the entire underside of the bed and wheel tubs in raptor liner 2k, got the top side of the frame cleaned up and all that
Upon sender removal I saw nothing restricted that would've caused my issues. Oddly enough the violent launch must have jarred the sending unit float arm in the empty position and had an 1/8th in of a stiff spot. Maybe im thinking irrationally, im wondering if I had some sort of cavitation issue this whole time. Since the replacement ive beaten the brakes off this thing with logs and am not seeing any sort of difference between desired and actual frp. The next time im at the track im going to log it just in case, oddly enough the one log I recorded on snap won't let me upload the file. May have to upload to YouTube and then transfer onto here
Upon sender removal I saw nothing restricted that would've caused my issues. Oddly enough the violent launch must have jarred the sending unit float arm in the empty position and had an 1/8th in of a stiff spot. Maybe im thinking irrationally, im wondering if I had some sort of cavitation issue this whole time. Since the replacement ive beaten the brakes off this thing with logs and am not seeing any sort of difference between desired and actual frp. The next time im at the track im going to log it just in case, oddly enough the one log I recorded on snap won't let me upload the file. May have to upload to YouTube and then transfer onto here
Update. Raced last friday, something fueling wise is definitley going on. I put 5 more gallons in on the way to the track, possibly got bad fuel.
First pass was tune 3, 12.90@103, first on the hot tune was 11.96/114, truck started to flat line up top, not sputter as it did before. Just completely stopped pulling. Following passes got slower, truck is 60ft'ing like shit, tenth slower in the 1/8th, 2 12.0 passes after and I stopped racing for the night. Truck used to run 11.90 in tune 4, tune 5 was best of 11.88. Last pass I data logged off my Matco scanner, definitely was losing rail on desired and actual. Im unsure if my valley cp3 is failing and the brain box for the 2xcp3 is shutting off the valley pump, bad fuel or something else im missing. Thought it was odd both dipped off like that, I was expecting it to have a significant difference between desired and actual. My scanner does show a delay but it seems it dropped to 12k for that second or two. The FPR has stuck before and tcw3 cleared it up.
Oddly enough a friend that was recording captured the 11 sec pass with consistent smoke the entire pull, and the last running my buddies zl1 and ZERO smoke output in 5th gear
I've ordered new fuel filters just to be sure, cleaned the maf since its had an intermittent flat spot the last week and need to find data/log to ensure maf readings are within spec (also unsure if OE is gm or Hitatchi like mine is). Ill probably do a 2 stroke cocktail again to see if things clear up or remain unchanged.
First pass was tune 3, 12.90@103, first on the hot tune was 11.96/114, truck started to flat line up top, not sputter as it did before. Just completely stopped pulling. Following passes got slower, truck is 60ft'ing like shit, tenth slower in the 1/8th, 2 12.0 passes after and I stopped racing for the night. Truck used to run 11.90 in tune 4, tune 5 was best of 11.88. Last pass I data logged off my Matco scanner, definitely was losing rail on desired and actual. Im unsure if my valley cp3 is failing and the brain box for the 2xcp3 is shutting off the valley pump, bad fuel or something else im missing. Thought it was odd both dipped off like that, I was expecting it to have a significant difference between desired and actual. My scanner does show a delay but it seems it dropped to 12k for that second or two. The FPR has stuck before and tcw3 cleared it up.
Oddly enough a friend that was recording captured the 11 sec pass with consistent smoke the entire pull, and the last running my buddies zl1 and ZERO smoke output in 5th gear
I've ordered new fuel filters just to be sure, cleaned the maf since its had an intermittent flat spot the last week and need to find data/log to ensure maf readings are within spec (also unsure if OE is gm or Hitatchi like mine is). Ill probably do a 2 stroke cocktail again to see if things clear up or remain unchanged.
Wild guess but it sounds like a fuel temperature issue. Getting hot. If I'm not mistaken, there is a temperature table for fuel pressure and the hotter it gets the more it lowers pressure.
If you log fuel temperature and pressure and notice it corresponds, then I would look into your fuel cooler and pickup up
If you log fuel temperature and pressure and notice it corresponds, then I would look into your fuel cooler and pickup up
Actual and demanded should match though, regardless
Do you have a way to monitor fuel pressure from the lift pump? You need to make sure that thing is outputting 7+ psi during the whole run.
I appreciate that bit of info, and anything is possible. I let the truck sit for 2hrs before making my first pass and friday was probably the coolest day in summer we've had here in IL it was 73. Im gonna have to log that now as well, this is an issue i need to resolve for sure.
I fully agree. The only other time ive seen it be 6k off was after the 67mm prior to 65s and the dual fueler setup
Im glad you brought this up, I forgot the airdog rep I spoke to last season mentioned I should go to the 220 I believe? I do not have anything on there to do so at this time. I can always run a line and a gauge up behind the hood for a makeshift log
I thought he mentioned they both dropped off. But after reading it again, I can see how I miss interpreted it
I’d be checking that. We need to make sure supply is consistent. Dont throw a bigger pump at it yet, i cant see you taxing that 165 yet.
You read it right, both actual and desired dropped off. I would look at all the tables that would limit fuel pressure. Then log those tables and see what’s happening. Could be a bad sensor or wiring problem.