Another datamaster check please

randy merritt

randy merritt

Donating Member
Re: Another datamaster check please

Just looked, does it feel like your trans is slipping? After the 2-3 shift, the rpm's are pretty flat, even though you are 100% throttle. When you gunned it, it should have downshifted, as you were only traveling about 15 mph. There should be distinct peaks and valleys. Your TC does not lock until 70 mph, there is something wrong there. The boost is jumping all over the place. I would guess either the TV cable is out of adjustment, or you TC or trans is toast. I could be wrong. Not really sure about the boost, as I am not familiar with the stock boost controller.
 
sytyguy

sytyguy

Moderated User
Re: Another datamaster check please

What mods? Assuming mostly stock........if so, looks pretty good considering. I would consider getting the EGR deleted if you can (emissions) as it's escalating your intake temps considerably (the only knock you get is once the intake temps get above 190 degF. EGR delete alone will help you pull 60-70 degF out of the intake. Might not be much of an issue at the track when it won't be active and you can ice the intake/IC, but it's something to consider soon IMO. Some WG tweaking would be good too (to get boost as close to 15 psi as possible).

Just noticed what Randy is referencing, keep in mind that stock chips only allow 100% TPS TCC lock at 65 mph and up. Using S/D calc you went from 12mph to 81mph in 12.49 seconds. From a roll in a stock truck with 170-180 degF IATs, that's not bad, and not indicative of drivetrain issues. Not saying you couldn't have some (I haven't driven your truck), but TO ME, this DM log doesn't indicate that.
 
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pearl91chevy

pearl91chevy

Donating Member
Re: Another datamaster check please

awsome im glad its looking alright.. i was told it was a pitbull chip but i havent looked for myself to check.. and yes its mostly stock, its got upgraded fuel pump and a fuel regulator, 3"cat back exhaust and a filter on the crossover pipe.. i have no emissions here so just capping the egr is no problem??
 
sytyguy

sytyguy

Moderated User
Re: Another datamaster check please

I would get a run of a simulated quarter mile run (if you can find a stretch to allow it). If not, do an eighth mile run and post it. Would be nice to see how things are from a dig and we can calculate an estimated ET based on the log.
 
sytyguy

sytyguy

Moderated User
Re: Another datamaster check please

pearl91chevy said:
awsome im glad its looking alright.. i was told it was a pitbull chip but i havent looked for myself to check.. and yes its mostly stock, its got upgraded fuel pump and a fuel regulator, 3"cat back exhaust and a filter on the crossover pipe.. i have no emissions here so just capping the egr is no problem??
Click to expand...
Simply blocking the EGR will get the desired effect, but will result in a check engine light until the chip is updated to not turn on EGR. For the sake of this upcoming run, I wouldn't stress....not an issue when running the 1/4 mile and the truck is cooled and iced. Longterm, yeah, I'd remove it and get the chip reburnt to kill the EGR (or wait until you do some mods and then do a whole tuned up chip to match).
 
randy merritt

randy merritt

Donating Member
Re: Another datamaster check please

sytyguy said:
What mods? Assuming mostly stock........if so, looks pretty good considering. I would consider getting the EGR deleted if you can (emissions) as it's escalating your intake temps considerably (the only knock you get is once the intake temps get above 190 degF. EGR delete alone will help you pull 60-70 degF out of the intake. Might not be much of an issue at the track when it won't be active and you can ice the intake/IC, but it's something to consider soon IMO. Some WG tweaking would be good too (to get boost as close to 15 psi as possible).

Just noticed what Randy is referencing, keep in mind that stock chips only allow 100% TPS TCC lock at 65 mph and up. Using S/D calc you went from 12mph to 81mph in 12.49 seconds. From a roll in a stock truck with 170-180 degF IATs, that's not bad, and not indicative of drivetrain issues. Not saying you couldn't have some (I have driven your truck), but TO ME, this DM log doesn't indicate that.
Click to expand...

Good stuff, and again, I am not to familiar with stock setups. It still seems like the truck should have downshifted when it was punched from a rolling speed of about 15. Am I missing something?
 
sytyguy

sytyguy

Moderated User
Re: Another datamaster check please

How do you launch (what method)? At what psi?

Looks like you left with about 8-9 psi on the launch in this log. If you did, you may have introduced some wheelspin that hurt you as the 0-60 time (using the log) are pretty poor (6.8 sec or thereabouts). Make sure you're getting as good of a launch as possible (very important to take advantage of our 0-60 prowess, cause after, that it's less than impressive (in stock trim). Some trucks launch better (60' wise) by leaving at lower boost. Food for thought.

Couple of things that are clearer with this log.

- Definitely ice the intake/IC on race night. The cooler IATs will help give you some extra timing from the chip and make more power by cooling the charge.
- You have a boost control issue. Sloppy WG rod, leaking vac line, erratic solenoid, something.... You saw as low as 10.3 psi and as high as 15.4 psi on that run in a 2 second span. Get that fixed and get some steady boost control. Remember that if your exhaust is TOO free flowing, it can hurt you on boost control.
- How does the 2-3 shift feel at WOT? Randy may be on to something as there is a lull between frames 129 and 156. Notice how it takes nearly 4 seconds to get from 3300 rpm to 3600 rpm. Seems very lethargic. However, that does coincide with a tremendous drop in boost (and subsequently, Inj DC), so you may have a side effect there of an underlying issue (reduced raw power output from less than optimal boost control).
 
pearl91chevy

pearl91chevy

Donating Member
Re: Another datamaster check please

thanks for all the help on this..

this time i did a few revs in n, then went threw the gears manually.. yes held the brake hard as i could and built boost right before i felt it rolling and left off.. there was no wheel spin, ive only spun those tires from a stop once "275's"..

as for boost control, i did not re-adjust the wastegate yet, i wanted to get another run in before i started messing with that.. ill possibly adjust it this weekend or tomorow night... the exhaust is stock from turbo to cat, then after cat its 3" all way back behind axle w/ no muffler. is there a way i can test the stock boost solenoid? i Might be able to find a manual boost solenoid if needed..

as for the long shift.. that also has me wondering.. if i leave it in drive.. and just under normal driving, it shifts great from 1-2.. then from 2-3 well hard to explain.. goes threw 2nd just fine but kinda hangs a bit from 2-3.. then to get in 4 or overdrive i have to be at 40mph or quicker.. im gonna look into the tv cable adjustment and hope that fixes my problem.. i might even get a video tomorow after work of it shifting.. but besides that, kinda confused on what you mean about a underlying issue.. you think it could be a boost issue which is why it hangs?? even on that run it did feel sluggish when it hit 3rd and i did mention it before in a old post and thinking it was a clogged cat but once i did the tuneup it felt much better but its still there obviously
 
sytyguy

sytyguy

Moderated User
Re: Another datamaster check please

If you're having 2-3 shift issues under partial load as well as WOT, then you may have a genuine drivetrain issue. Does the 1-2 feel firmer than it used to? Verify proper TV cable adjustment first.

Try launching at a lower psi and see if it feels stronger out of the hole. Record a log and we'll compare the 0-60 estimates. And don't assume that tire width dictates wheel slippage. Wider tires often spin easier due to compromising on sidewall height (and thus flexibility in most cases). Calculated contact patch isn't everything.....sidewall flexibility is just as important if not more.
 
pearl91chevy

pearl91chevy

Donating Member
Re: Another datamaster check please

i dont know about used to.. the 1/2 shift is pretty firm.. ill search around for proper adjustment

and ill get a few more runs tomorow and post up, supposed to rain though but we'll see..
 
pearl91chevy

pearl91chevy

Donating Member
Re: Another datamaster check please

sure enough it rained all day, so no logging... did find a good power invertor for 30 bucks from harbor freight.. hopefully ill do a few more runs tomorow if weather is decent.. should i do a few more runs on the current set up or should i adjust a few things like the wastegate?
 
sytyguy

sytyguy

Moderated User
Re: Another datamaster check please

I wouldn't worry about more logging until you check out the TV cable and boost control issue.
 
pearl91chevy

pearl91chevy

Donating Member
Re: Another datamaster check please

so i searched around and cant seem to find a how to of actually adjusting the tv cable properly.. only threads saying it might need to be done.. i searched google and found that if i press the tab in on the adjuster for tv cable, give it full throttle and let go of the tab, thats where it needs to be.. this correct??
 
fauXGT

fauXGT

Brick Pilot
Re: Another datamaster check please

Think thats what I did after I put the shift kit in the ext cab. Unlocking the TV cable, full throttle to adjust and done.
 
pearl91chevy

pearl91chevy

Donating Member
Re: Another datamaster check please

alright ill do that tommorow morning.. while i was out there i checked the wg rod.. i could wiggle it around but when i tried to move it side to side there wasnt really any movement
 
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