383 loses power above 4000rpm

[greasemykey]

i built the engine and had Synergy set up my tune. i never got a chance to have it dynoed before i moved out to Virginia when i was discharged from active duty. before i left the truck would lose power above 4k. i thought i had a fuel pump issue but i have 70psi running and 60psi under a load driving. im currently running 93 octane with a mix of cam 2. here is my tune. i was told that my VE tables are off and my timing at WOT is low. not sure where i need to adjust or how much i should. any advice would be awesome. thanks for taking the time to look.

2000 Silverado ECSB 2WD Stage 3 Jakes 80E, Circle D 3600, 383 stroker, PRW roller tip rockers 1.7:1, ARH LT, HF Cats, NNBS intake, 90mm Edelbrock TB, 57lb/hr fast injectors Flowmaster 40, E-fans, Manley forged rotating assembly, Volant CAI, PRC 2.5 5.3L heads, Comp 228/234 112

[Mudweizer]

Your cylinder volume is off, should be .78453125

[SultanHassanMasTuning]

well your timing is low for NA

[greasemykey]

what should i adjust and how much timing should i add to start?

[greasemykey]

i have a fuel issue. tried to idle it to warm it up and my passenger cat was glowing.

[cesar]

because your timing is too low, try to add at least 5 degrees of timing or so

[gagliano7]

Make sure your cat isn't clogged.

[greasemykey]

cats are now gutted. still not seeing a change so either my plugs are fouled, coils are weak (original square coils with 230k) or my stock pump is not providing enough volume

[POWERZONE]

Well your PE TPS is a little high for my taste. I like the PE to come in a little sooner.

Timing up top is a tad bit low for a NA app.

I would need to see a log.

[greasemykey]

here is a data log

[MikeOD]

I run 23-24 degrees of advance NA in my LS3...looks like you're probably down around only 15-17...that'll make it feel like a turd.

[MikeOD]

...also in your data log, your TPS only gets to 89% very briefly...surrounding that moment it's at 80%, and power enrichment isn't enabling (look at the STFT between frames 585 and 620 to see what I mean). Also for the brief moment when PE does enable, (Frame 602-606), the narrow band O2 sensors show it's incredibly lean.

Also, when in closed loop, I see no LTFT data, but the STFT is hitting 53.9%. You NEEEEEEEED to work on the VE table.

[mowton]

2000 silverado.cfg

Mike is right, I was in the middle of creating a new .cfg for you to log with. See above. Please stay away from WOT until you get your fueling straightened out. Do you have a wideband? If not, no WOT tuning until you get on integrated to your scanner.

Your FTC are off, I think mostly because of the lack of vacumn. I assume that is because of the cam, but make sure you don't have a vacumn leak. Additionally you don't seem to hit 98-101 kPa when WOT (TPS 89%) which is strange unless you are tuning at the top of Mt. Everest :-)

For PE, you are not attaining the expected kPa so setting it to my favorite MAP enable 85 kPa and throttle (hot and cold) to 20, wont work either. Your log shows actually a reduction in IPW when the PE is enable??? Determine why you aren't attaining WOT vacumn. Make sure the Throttle Blade can open all the way based on the DBC setup.

Hope this helps

Ed M

[POWERZONE]

In your VCM scanner Table(primary) delete Mass Air Flow (SAE). You do not need this since you are SD and it will screw up your timing tables in your histograms.

As others have suggested, DO NOT GO WOT until you get a wideband and you fix your VE table. You are severly lean.

If you are gonna wait until 80% to 70% TPS before the PE kicks in, you better have your VE table tuned well.

[greasemykey]

I didn't set this up. I paid a tuner to get it to run and drive. he wouldn't dyno until I broke the engine in. on the other hand I have no clue what the hell im doing to where to start making adjustments. I do have a wide band and its going to get installed this weekend if I have a minute to myself. any help to idiot proof my adjustments would be awesome and much appreciated.

[nkautz]

You're super lean , look at your STFTs +50. I would pay to have the car dyno tuned. If you want to tune it yourself , wideband is an immediate must and you've got a few months of learning and testing ahead of you.

[greasemykey]

I agree about paying to have it done. but the last thing I wanted to do was waste a tuners time. I want to get it running well enough to drop it off and accomplish a dyno session. knowing know that my issue is TPS and tune related im going to get the TPS sensor to function properly and install my wideband. once that is done I will get the truck on the dyno.

[nkautz]

Dyno tuners are usually capable of tuning more than just wide open throttle. Any respectable tuner will know how to tune idle , part throttle , and everything else. People tow their cars to get dyno tuned all the time because sometimes getting it to idle and cruise is actually harder than WOT tuning. WOT tuning is actually pretty easy , there are much fewer variables.

[MikeOD]

I didn't set this up. I paid a tuner to get it to run and drive. he wouldn't dyno until I broke the engine in. on the other hand I have no clue what the hell im doing to where to start making adjustments. I do have a wide band and its going to get installed this weekend if I have a minute to myself. any help to idiot proof my adjustments would be awesome and much appreciated.

With what he left in it for a tune, you're lucky you didn't break it...nevermind break it in.

[greasemykey]

I did break it but not because of the tune. I broke a crap comp cams valve spring and slammed a valve into a piston.