WS6 Tune - Multiple issues

[tpy2kws6]

As suggested I'm posting this tune. Not my work as I was not really familiar with tuning at the time this tune was done(which was a while ago). I'm still learning and have been going through the board, using gregs dvd, and tuning school material to help broaden my knowledge. Before this tune I had a predator tune which was a custom one due to the camshaft but the car felt so much better with that tune.

Mods:
TR224 (112)
QTP 1 3/4 LTs
Magnaflow Catback
LS6 Intake
Lid
Green Top Injectors
Pulleys
Racetronix Pump
125hp HSW Plate(Setup but never used yet because car didnt feel right)
9in with 3.90s
Dynojet w/b

So when I had it dyno tuned they strapped it down and went for a base line. Injectors were at about 95% dc so they suggested injectors. I said ok and they said the green tops were the way to go.

Lets start with the idle, cold idle is really bad (surging and rolling). Once its warm idle is smooth but the car really stinks. A few things I noticed was that none of the injector data except the flow rate were changed and the ve table has a weird ridge at the lower rpm range.

The car feels very unresponsive compared to what it felt like when the predator tune was in. Throttle response is very soft and wot is not what it was before. I know the butt meter isnt a good guage but the whole overall attitude of the car is off. I noticed that the ve table (with the exception of the low rpm area) is virtually unchanged from stock. Unfortunately I didnt pull the predator tune out before I had this done so I cant compare to that but when compared to stock the ve appears to be almost identical.

I was told the only change I would need to make if I wanted to run nitrous was to pull 4 degrees out of the timing table in the wot areas.

I'm already working on an updated tune with the injectors setup correctly using gregs dvds as a guide. Not sure if just doing that will solve my idle problem but I feel I cant go any further till I get that right. Any suggestions would be greatly appreciated. I dont have access to a dyno but I think I'm correct in assuming that even with this small cam the ve has got to be changed. Is it realistic to think I can get a good ve on the street without a dyno? I miss the snappy feel this car once had...

Once I get the driveability is straightened out Ill deal with WOT. Thanks in advance for the help.

[oakley6575]

I'm not a professional, but last summer I built a 408 with an LS3 top end and a custom spec'd cam. Once I got it in the truck, it went directly to the dyno for a tune. I picked it up the next day and wasn't happy at all. The truck only ran good above 4000 rpms. Cruising was terrible, and idle/startup was even worse.

I tuned the VE table and MAF up to 4000 rpms using fuel trims. It almost cured all of my problems. I think you should start there after you get the correct injector data. That cam definitely needs alterations to a stock VE. Good Luck

[WS6FirebirdTA00]

You idle area needs work anyway, fixing the injectors won't help. Your idle is lower than stock. Might be best to start with a stock file and then work from there. That way you make slow changes without any of the other tables messing you up in the background. Set your injectors, put in a base timing table (don't need all that timing they have in there at high load), set your idle RPM to a reasonable value to stability (850-900 RPM) then do a cold start log to get your idle air close. You will want to start tuning the MAF and VE tables before finishing idle, as that could change it. You will more than likely have to mess with throttle cracker and follower tables for idle stability while rolling and coming to a stop, although it is not always the case.

[tpy2kws6]

You idle area needs work anyway, fixing the injectors won't help. Your idle is lower than stock. Might be best to start with a stock file and then work from there. That way you make slow changes without any of the other tables messing you up in the background. Set your injectors, put in a base timing table (don't need all that timing they have in there at high load), set your idle RPM to a reasonable value to stability (850-900 RPM) then do a cold start log to get your idle air close. You will want to start tuning the MAF and VE tables before finishing idle, as that could change it. You will more than likely have to mess with throttle cracker and follower tables for idle stability while rolling and coming to a stop, although it is not always the case.

Thanks, I'll take your advice and start from a stock file. Its kind of frustrating because I spent a good chunk of change when I had the car tuned but hey now I get to use it as a learning experience.

[WS6FirebirdTA00]

I feel your pain, indirectly. I've retuned a lot of cars that made me sick people actually paid for it. Lots of people are in the same boat. They get tunes like this and don't know what "good" is, so they think their tune is fine. If you go from bolt ons to head and cam, it will feel fast no matter how crappy the tune is and the hiccups most people have they assume is just the nature of the cam - not always the case.