What am I missing? No more power after cam/intake swap
The following users liked this post:
00pooterSS (10-03-2019)
10-03-2019, 01:38 PM
#12
Staging Lane
Thread Starter
So just got done talking to the tuner, he wasn't there when I picked the trucked up........sounds like the ARH cats might be going to ****, could smell them when he had it on the dyno apparently. He did everything he could to get more power out of it, more/less fuel, timing but it just hits a physical wall, which points to a restriction in either the intake/exhaust. The cats being the likely culprit, im going to pull them and redyno to hopefully find the 40+hp I'm missing lol.
The following users liked this post:
arthursc2 (10-03-2019)
The following users liked this post:
00pooterSS (10-04-2019)
11-04-2019, 09:23 AM
#18
Staging Lane
Thread Starter
Update
Sooooo, pulled the intermediate pipe off, cats didn't appear to have any physical damage/restriction but i rodded them out anyways because who needs those silly things. Afterwards the trucks idle immediately improved then I left for work for two weeks, got back home degree'd the cam/checked valve train, checked both intake and exhaust restriction, all good, after having the battery unhooked for a few days the fuel trims reset and the truck went back to hard starting/idling like 
. Took the truck back to tuner guy, left it with him for a few days and same story, no change in power, and starting/idle was worse 
..............pulled intake, checked injectors for spray pattern, replaced knock sensors (because why not) and I also replaced the cam position sensor, i didn't have a fault code but i thought it might be failed/failing due to hard starting and because i had no continuity across any off the pins and couldn't read a AC or DC signal across any of the pins when waiving a magnet/metal in front of it, which apparently is just how they are because the new one is the same way??.............at this point i was pretty much over it and just wanted to set the truck on fire, cooler heads prevailed and I got curious, so i hooked up the laptop and was able to read the tune file written by tuner guy. First red flag was that he hadn't desensitized the knock sensors at all, no changes to transmission settings, leaving torque management active yada yada. So i decided to re flash it with the original tune i had written by BB, Idle immediately improved and the truck feels like it pulls much harder. I know the butt dyno is very subjective but i have alot of time behind the wheel of this rig, spaced out over varying degrees of modification and my buddy has almost the exact same truck with a muffler/cold air/diablo 87 tune so i feel like the butt dyno is pretty calibrated to tell if mine is actually pulling harder. How much more power am i making if any?? Guess ill never know lol............after reading a little bit about the mustang dyno and the rpm calibration procedure, i recalled that on the initial baseline dyno run tuner guy was having a shop hand "set" the rpm calibration on the dyno machine when he honked at a certain rpm (2000 I think)..........mind you the kid was standing right next to the exhaust pipe and the had to do this procedure a few times. I didn't realize the significance of this until after i read about the calibration procedure and how it can affect power numbers, also in all the subsequent dyno runs i saw tuner guy was performing this initial calibration from the driver seat of truck with a remote. So i feel like its entirely possible the initial dyno run read abnormally high, and all the after cam/intake runs were closer to what the truck is actually making.........what are the odds of those two runs being nearly identical?? IDK at this point so many potential variables have changed the whole purpose of a before/after mod dyno run has been defeated 
interesting side note, when i was checking my cam degree/valve train i noticed that when torquing the rocker arm, the valve was moving a few thousandths off seat, after initially losing my mind i discovered this was happening due to lifter preload/hydraulic resistance in the lifter and that it bled down after about 30 seconds allowing the valve to return to 0 (measured with a dial indicator). I had considered that the factory lifters might not be up to the task of opening the BTR dual rate platinum springs fully due to the shock absorber effect hydraulic lifters can have leading to poor power levels, but after seeing that the tolerances within the lifter are still tight enough to overcome 155 lbs of opening pressure for a few moments im fairly confident that's not the case.
. Took the truck back to tuner guy, left it with him for a few days and same story, no change in power, and starting/idle was worse ..............pulled intake, checked injectors for spray pattern, replaced knock sensors (because why not) and I also replaced the cam position sensor, i didn't have a fault code but i thought it might be failed/failing due to hard starting and because i had no continuity across any off the pins and couldn't read a AC or DC signal across any of the pins when waiving a magnet/metal in front of it, which apparently is just how they are because the new one is the same way??.............at this point i was pretty much over it and just wanted to set the truck on fire, cooler heads prevailed and I got curious, so i hooked up the laptop and was able to read the tune file written by tuner guy. First red flag was that he hadn't desensitized the knock sensors at all, no changes to transmission settings, leaving torque management active yada yada. So i decided to re flash it with the original tune i had written by BB, Idle immediately improved and the truck feels like it pulls much harder. I know the butt dyno is very subjective but i have alot of time behind the wheel of this rig, spaced out over varying degrees of modification and my buddy has almost the exact same truck with a muffler/cold air/diablo 87 tune so i feel like the butt dyno is pretty calibrated to tell if mine is actually pulling harder. How much more power am i making if any?? Guess ill never know lol............after reading a little bit about the mustang dyno and the rpm calibration procedure, i recalled that on the initial baseline dyno run tuner guy was having a shop hand "set" the rpm calibration on the dyno machine when he honked at a certain rpm (2000 I think)..........mind you the kid was standing right next to the exhaust pipe and the had to do this procedure a few times. I didn't realize the significance of this until after i read about the calibration procedure and how it can affect power numbers, also in all the subsequent dyno runs i saw tuner guy was performing this initial calibration from the driver seat of truck with a remote. So i feel like its entirely possible the initial dyno run read abnormally high, and all the after cam/intake runs were closer to what the truck is actually making.........what are the odds of those two runs being nearly identical?? IDK at this point so many potential variables have changed the whole purpose of a before/after mod dyno run has been defeated interesting side note, when i was checking my cam degree/valve train i noticed that when torquing the rocker arm, the valve was moving a few thousandths off seat, after initially losing my mind i discovered this was happening due to lifter preload/hydraulic resistance in the lifter and that it bled down after about 30 seconds allowing the valve to return to 0 (measured with a dial indicator). I had considered that the factory lifters might not be up to the task of opening the BTR dual rate platinum springs fully due to the shock absorber effect hydraulic lifters can have leading to poor power levels, but after seeing that the tolerances within the lifter are still tight enough to overcome 155 lbs of opening pressure for a few moments im fairly confident that's not the case.
11-04-2019, 11:18 AM
#19
Really glad it seems to be all sorted out man
I hate people that do shitty work and run you in circles because they're too lazy to give a **** about the quality of their work
Blast the tuner on his website and maybe help keep some other people from getting screwed
I hate people that do shitty work and run you in circles because they're too lazy to give a **** about the quality of their work
Blast the tuner on his website and maybe help keep some other people from getting screwed
11-04-2019, 12:40 PM
#20
Staging Lane
Thread Starter
I really don't think the guy was trying to screw me, giving him the benefit of the doubt, maybe he was just trying to be cautious working under the assumption there was something mechanically faulty with the truck?? Without asking him why he did or didn't do this that or the other it's hard to say, and with my limited knowledge of tuning he could be feeding me total bullshit or actually being sincere and I might not know the difference, dont really feel like opening that can of worms and starting a pissing match over why it didn't perform better on his dyno. This just reconfirms that if you want something done right do it yourself, but as far as the tuning is concerned I'm still at the mercy of others lol, hope to fix that in the near future.