Hey all,

Im pretty new to this whole C5 mod hobbie and am in need of some direction. I have decided on my first set of mods being headers and cat back. The exhaust vendor said i would need a "tune" after the install of these mods.

So doing some research here on the forums i found varying info on tunes and am wodering what is right for me. My extent of future mods will be Intake, tb, thermostat and CAI along with the exhaust.

What is the best option for me? HPtuner, EFI live, hand help programmer (Diablo predator etc), dyno tune, regular ole tune. I dont know all the differences and based on my plan what do you guys recommend?

Thanks for any help you can pass along.

Curtis

 

I see that you are in calif---so the Lt's will require some help in getting them to pass smog--typically the LT's will make you run rich during PE and you will need to get it tuned to get the full benefit of them--Also to pass calif emiisions you'l need to get a shop to overlook the visual test ... then also the 02 sensor locations on the headers will cause your closed loop fueling to be richer than normal too--So it won't pass beacause of this --you'll have to get someone to work on your VE table and your 02 switching points to get the AFR back to 14.68--somene with a wideband-
I would say absolutely a hand held is out--a full tuner is called for like EFILIVE or HP Tuners--If you don'rt want to learn the software your best bet would be to take it to a dyno shop with a tuner/programmer on staff to correct all the issues--

 

Hum, so going with the LG pro street with cats is going to give me smog issues you think? Or is that only without a tune? or will the tune correct that?

Is there any easy way to find a tuner shop? or will any motorsports, hot rod type shop have the capability?

Sorry for the beginer questions!

 

YES ALL long tube headers are illegal in Calif.----however most smog shops (at least in my area) will let them pass the visual test and as long as they pass the emmisions tests , they will pass them overall--make sure you hook up the A.I.R. tubes--
The power enrichment tuning on the dyno is just for added performance-Without it you will only get 5-10 HP--But when tuned you can usually get 15-25 HP easily-
One of the major issues you run into is that the 02 sensor bungs on the headers are further aft than in the stock location--this sometimes will give your computer false information to the AFR in closed loop operation ( basically all part throttle positions) and the commanded AFR of 14.68 won't now be the actual AFR--It will be something much richer---Mine was at 12.88----This much fuel will raise the hydrocarbons pass the limit and fail the test--Any good tuner will know how to correct this for you---There are many tuners here but I have no idea if there are any in your area--You may have to go to the Sac area or to the Bay area to get it tuned and smog legal--Not just any hot-rod shop can do these changes---You have to find someone who specifically can program GM gen 3 engines/LS1/LS2's etc--They must have EFILIVE or HP Tuners software--

 

I thought there were a couple of LT headers that were CARB approved, do a search in C5 tech.

 

Sincleanser,

I can't speak to California emissions issues, but regarding "do it yourself," versus a professional tune -- definitely go with a professional tuner.

It'll be done correctly, with better adjustability, and save you a lot of headaches.