thunderstruck507

iTrader: (18)

So basically, I'm on a tight budget and will be for a while, but I'd really like the car to run "great"...doesn't have to be perfect, but I don't want to be leaving a ton on the table either.

So I'm wondering because I can:

A) send the logs and pcm back for a retune (cons are downtime on the car, still might not be optimal)
B) pay for credits and me and my friend can try to work it out with HP Tuners
C) shell out the $4-500 for a professional dyno/street tune

I'm pretty happy with most things about the way the car drives, so I'm less worried about intensive street tuning than just getting the most out of it WOT.

Would anyone here be able to tell by looking if I'm leaving much on the table right now without me having wideband o2 info too?

If the torque calculator function in HPTuners is accurate I am making about 15ft/lbs more now (closed cutouts versus open cutouts on dyno) than on the dyno since I've got my 92% throttle issue sorted out

Forgive me if this is a stupid/ignorant question, I'd just like to avoid the hassle of not driving my car for a week or more or blow $500 if I'm not going to see much from it.

LS1-450

iTrader: (33)

You can work out the tune w/ your friends HP tuners. You'll need his wideband as well. Lean out the air/fuel ratio during normal driving to 15.6-16.3:1. Ya gotta have the wideband in order to tune correctly. Too bad your friend doesn't have EFI Live, I could have sent a tune to get ya close. For WOT tuning, make sure you're getting 12.6-12.9 air/fuel. After the fueling is correct, he can play around w/ timing to get a little more. The great thing about using tuning software is that you can play around w/ the tune as long as you like & are not limited by time, like when you pay for a dyno. You can also do a better job on the street tune. So, option B is the best choice.

ZL1Killa

iTrader: (17)

have you already gotten it tuned from someone? usually they offer a re-tune price cut, as your PCM would already have been flashed and it only costs them time, not credits.

without Wideband and other info it is really hard to tell what is left.

either don't drive the car, or go back to your tuner/new tuner

AutomagicLS1

iTrader: (18)

I would pay your friend for a credit (from the get go) or buy HPT. Or maybe he will let you borrow his cable or with a deposit. That way you can do whatever you want and spend some time learning. It sucks when you need somthing changed and you have to chase them down + pay them for a reflash.

thunderstruck507

iTrader: (18)

its a mail order tune and he told me before if I could provide a log he could get the tune more precise for free

my friend currently doesn't have a wideband o2 is the only problem

Frost

iTrader: (45)

no way to know how far off WOT is without a wideband.

Somewhere or another, if you want things changed you can't avoid spending the money.

moehorsepower

iTrader: (3)

You should ALWAYS set money aside for tuning just like you do to purchase parts, Tuning is a no brainer, what I mean by this is that you should get a this done when any modifications are performed. What I dont understand is that most people will spend thousands of dollars on parts but leave out the one main item that will make it run...Yes get it tuned..

thunderstruck507

iTrader: (18)

I realize that, the money I had set aside for tuning went to:

replacing heads
replacing valvesprings a member sold me as comp 918s...turned out to be stock so I had to buy new ones
getting heads surfaced
head gaskets, head bolts, lifters
replacing a set of coil packs
changing to a different oil pan since stock turned out to not fit like it was supposed to

I think I'm going to see about us tuning it on the street, then get some cheap dyno time with wideband for wot tuning or see about helping him pay for the wideband

LS1-450

iTrader: (33)

You can't tune on the street without a wideband. I don't know how your friend has tuned, properly, without one.

DaveX

What are your motor mods? Cammed and aftermarket heads?

thunderstruck507

iTrader: (18)

and now you see why I'm reluctant to try the tuning myself...I don't know much about it

cammed and stock heads (long story short a miscommunication led me to believe my 98 heads were not usable so i got a set of 99 heads, found out nothing was really wrong with the others so i just used the 99s anyway since i already had center bolt coil brackets, noone wants to buy the others)

Lopoetve

iTrader: (1)

For me at least, it's because tuning it is a 3000 mile round trip to texas - no tuners in Colorado, and I don't know nearly enough to start doing it myself. I'm holding off on buying some parts till I can take a week off to get to Texas Speed and have them do it - I think they're about the closest around. edit: the closest that has a clue what they're doing.

Finding parts is easy - those get shipped to you. Finding a tuner - that's hard, and you have to go to him.

thunderstruck507

iTrader: (18)

one big question that I have is why my injectors are hitting 95-97 duty cycle at 6000rpm...is that normal?

98ls1
99 heads (unported)
ls1 intake, ported tb
comp 230/224 111+3 xe lobes

I was under the impression stock injectors would be more than plenty

LS1-450

iTrader: (33)

No, it's not normal. 80% or there about max (rule of thumb).

moehorsepower

iTrader: (3)

That is unusual, we usually see the need for larger than stock injectors when a combo of ported heads and cams are installed. could be a number of things, injectors are just wore out, pump failing causing the pcm to force the injectors to work harder and in tuning. the IFR could of been adjusted wrong and someone used the PE mode to maintain a certain A/F....

thunderstruck507

iTrader: (18)

the pump is brand new so I hope its not that



EDIT: I dunno if it makes any difference but he didn't change his logging setup from the one he uses on his GTP

Frost

iTrader: (45)

or it just has never been tuned

DaveX

Tuning with a wideband is something you need to do before you even drive it much more. What is your AFR at wot? If you don't know, don't run it hard.

thunderstruck507

iTrader: (18)

well it was supposed to be tuned to run with the cam when I sent for the mail order, I've been driving it for a good while, since september

I guess if I can ever find a damn job I'll try to do a dyno pull here with a/f and see, unless I stumble across a job good enough I can afford to just take the damn thing to tulsa or longview



should I hook up a fuel pressure gauge and run it to the cowl scoop so I can see if it's losing pressure? running in the shop it always had over 50lbs at the rails

LS1-450

iTrader: (33)

Should be 58psi @ the rail. On the street w/ a wideband is better than a dyno, IMO. So, once you can afford it, get the wide band (maybe you & your friend can go halves on it) & then pay for the HP tuner credit.