Mods, Tuning & Gas Mileage
Thread Starter
TECH Enthusiast
iTrader: (1)
Joined: Sep 2008
Posts: 584
Likes: 0
From: Fairfax, Virginia
Mods, Tuning & Gas Mileage So I had a comp cam (236/242, 114 LSA) installed in my LS6 crate engine, along with all the supporting mods. Also had 42# injectors installed. The car was dyno tuned before and after the injectors (I had them installed about 2-3 weeks after the engine install). I'm noticing that I'm getting TERRIBLE gas mileage. Granted, I understand that a cam is going to affect gas mileage to an extent, but I'm getting only 120-150 miles out of an ENTIRE tank!! And that's with normal/non-spirited driving, shifting around 2-2.5k RPMs. Is this normal? I notice a somewhat strong smell of fuel while the car is running, but I attributed that to having no CATs. Is something not right with the tuning of the car? I just feel that the gas mileage is much lower than I had expected, or maybe I'm coming to find out that I didn't have serious expectations for gas mileage after all the modifications to begin with. Mods are in sig.
Something is way off, a cam should not make you lose that much gas maybe 2-3mpg. I would have your tune looked at again. Check and see if they put in the right info when the swapped the injectors out, I had this happen to me and it made a big difference. I was getting around 190 miles on a full tank and after I looked over the tune I noticed the injectors were not set up right fixed it and I get 220 miles on a full tank. Not saying it's your problem but could be.
Thread Starter
TECH Enthusiast
iTrader: (1)
Joined: Sep 2008
Posts: 584
Likes: 0
From: Fairfax, Virginia
Frost, yeah I've already checked you out and I have been looking to set up some time to come down and get you to have a look at it. Funny that you jumped the gun on me and initiated contact! Haha
Trending Topics
Honestly, when mileage is bad, the front O2s are suspect. They control most all of your fueling except for first startup and WOT. If they are bad (the don't always code) or if you have leaks near, around, or upline of them, mileage can really suffer.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Staging Lane
Joined: Jan 2009
Posts: 59
Likes: 0
From: Bella Vista, AR
Have Frost set your injector tables in the PCM to the correct values. These are obviously not set correctly and the injector pulse widths are too long for the larger injectors. If you did not touch the injector table to correct these values for the larger injectors then way too much fuel is being injected at all times regardless of RPM.