ricekiller06

i tuned mine myself and it worked great but wondering if i could goa little more. i added 3% more fuel top end. gave it 2 degrees of timing from 0-4000 RPMs. took away 3 degrees on top end. running it a little cooler but adjusting the fan. just wondering what everyone else did, trying to see if im on the right track is all

GrayPony

Everyone else buys a professional tune by an experienced tuner.

Rhino77

I wouldn't mess with any other tune adjustments, unless you're a pro tuner, don't wanna screw anything up.

68XR7

I'm kinda glad that you started this thread. I'm pretty sure that you bought a "professional tune from an experienced tuner" and all that, but I am curious about adjusting the user settings on the tuner to maximize the benefit to our particular vehicle.

chrisc

you really wanna be careful with that stuff, especially if you cant monitor your A/F ratios. all blown engines on the 4.0 have been bad tuning (or EXCESSIVE power)

Sancho805

its all about balances. an inbalance somewhere can be bad for your health.....but if you understand what you are doing, let us know your experiences with your adjustments. i'm curious.

ShadowWulf

Since we're on the subject of tuning, what would be some good ECU/EFI tuning resources? Things such as websites or books.

Wickerbill

So where do you stand now on your A/F mixture? Im also interested in your reasoning with retarding the timing at higher rpms yet adding fuel to the air fuel ratio? I would pull the plugs and check them also, I bet a dollar to doughnut they are white as snow.

28HopUp

I was at the track this week with a bunch of 4.0L nut-jobs, and the topic of changing tune parameters came up. At least one custom tuner that we all know will lock out the handheld tuner to prevent the owner from making any changes that could be disasterous. I know my heandheld tuner is not locked, but I was advised NOT to touch fuel & spark. I figured I paid for his experience in writing my tune, so I really doubt that I could improve on it. Changes like shift pressure and shift speed are something that I feel comfortable doing, and if my tuner was locked out then I would be SOL. Shoot, I use my tuner all the time to change tire revolutions between my street tires and DR's. So I would be ticked if my tuner was locked out.

To the OP, I would be VERY cautious about making tune changes unless you are able to monitor the air/fuel ratio.

boss 244

I change mine at the track, but I have not found an instance where me changing the fuel leaner or richer at WOT has helped me go quicker, I have upped timing with sucess and shift pressure.Ihave figgured what works on my car and that is all I do now, and leave the actual tuning to Alternative Auto.
More power to you though-tell us whatever results you get.