Slade wrote:
While I feel that mail order tunes can get you on your way, I have looked at a lot of so called mail order tunes and found they are too generalized. A street tune is not done in your sleep. It's logging, testing, verifying etc The mail orders get you going, but seriously they are not matched 100% to the combo as some imagine. There's a lot of "adjustment" that the LS1 PCM platform can do to compensate and make up for shortfalls in a tune. It is a "learning" ECM that uses its sensor inputs to the best of its interpretation to get stoich down so you can drive in most scenarios. Some people attribute this as good tuning when in fact the platform itself is very very reliable on that front.
A dyno tune looks at WOT. It gets you going with a decent MAP or MAF table along with power enrichment. The tuner can make adjustments specific to platform such as injector values, timing etc. It's FAR from optimal, it's just what works for the day and when you romp on it. The tuners rely on the LSx platform to self-adjust everywhere else to keep it drivable. A mail order also doesn't know if you went too lean or rich (they tend to err on rich to cover their asses) this is kinda playing with fire if you haven't been on a dyno to verify AFR or have a wideband to confirm. They also can't FEEL what you feel as you drive it. It's always a reactive response to the log you give. Intake leaks, internal problems, noises aren't accounted for. You could be leaking oil into the intake via valve seals, and the tuner sees rich on the logs and leans it out not realizing the log is wrong.
Tuners like Arun do some street tuning as well, but considering their schedules and clientele, its not possible to log most scenarios for a smooth tune which is optimal for all scenarios.
If you get HP Tuners or EFI Live, you will have a lot more power to log the sensors, weed out what is wrong and right with the interpretation and make changes to the base tables for everything that exists. This means your 250 donkey dick cam can idle with crazy lope or be almost smooth like stock. It means on a super hot day you can forget to have the a/c on max and still get a nice clean start on first try. It can mean not having an exhaust smell that is so rich the cars behind you decide to stop fueling themselves because you're providing the fuel for them. It means you can drive 600km on a tank at whatever "reasonable" highway speed you want or drive around in the city and net 400 km in stop/go commuting. It means a nice smooth idle that doesn't rattle your teeth.. .etc
Well all I can tell you is look at my cars #'s vs what my mods are and the fact that it has 130,000 miles on the odo.
I bet a great local tuner would be hard pressed to safely get more than 5 peak hp out of this thing.
I paid 150.00 for my first tune including shipping both ways,my subsequent tunes(2) were $75.00 shipped each.
My driveability is great and the car hauls ass,I am happy and I saved a pile of money. JMHO