Has anyone here done some successful mods to the 4.3l V6 to improve its performance and gas mileage?

I just purchased a 2004 Silverado 1500, short box regular cab. It's a very clean low mileage (50k) truck with a 5-speed manual trans and a 3.42 rear axle ratio. Driving over 500 miles at 65-70mph on the highway netted me a whopping 18mpg. I was expecting more. Plus, this engine seems a bit weak and like all good Chevy engines I'm sure it has some potential.

The truck is all stock with the exception of a dual muffler system that splits just behind the single stock catalytic converter.

I'd like to hear from some of you what you have done to improve this engine in terms of both performance and gas mileage. I'm not afraid to toss a cam in it either, if needed, or to rework the stock heads. I'm not looking to turn this thing into a fire breathing street truck, but I am sure that it can be improved upon in some key areas from where it is now.

And for those who want to post and tell me to just drop in a v-8......that mod is beyond my time availabilty, pocketbook and needs.

Thanks

 

I have a 97 work truck rcsb with a 4.3L and 5 speed. I also have 3.42 gears. I get regularily 18mpg in town and 22mpg on the highway. Absolutely zero mods other than no converter and a hypertech power programmer.

 

Save your money then and put it towards more gas

 

most do basic boltons without much gain. if they need power they install a nitrous system to get them by while they save to swap out the motor for a v8. those are really your only choices.

my honest opinion? trade trucks

 

hahaha... umm... best bet would be a custom tune not a handheld. and idk if the 04 has e fans or a clutch fan! but e fans help out too. honestly there isnt much hope for the 4.3L trust me i know. spray can help alot. but it gets costly after awhile!

plus anything other than bolt ons for the 4.3 get expensive. i know of people turboing the 4.3s but idk

 

buy an ebay intake and get it tuned and leave it be.If thats not enough put 150 shot on it

 

http://www.fullsizechevy.com/forums/...ds-4-3-v6.html

that's a decent place to start

 

My truck was a 05 4.3 5 speed 3.23 gear...i got about 15mpg city and 19-20 highway

After the 4.8 swap still 3.23 gear, i got 15 city still and about 21 highway.

Now with ls6 cam, intake, LT's, ORY, and exhaust OH and 4.10's i get 16.5-17 city, and 24 highway is my best.

But that is also with lean cruise.

Dustin

 

you'd do good to get a short throw shifter, too

and since yours is an 04, you can do the drill mod next time the trans or clutch need work