enasnitsi

I just got done performing the ignition upgrade that everyone on here mentions. I have a 96 f150 with the 302. It still had the original plugs, wires, and cap and rotor on it. I installed an msd coil, msd cap, rotor, accel wires and just the cheapest autolite plugs I could get. I set the timing at 13 degrees, it was at 8. It runs good but I didn't notice any gains at all. I was getting about 13.3 mpg before and now I have gotten 13.5 after running 600 miles on it and 4 tanks of fuel. Am I missing something here or what? I figured I would at least gain something from all this.

Any suggestions?

blade z51

I am doing the same thing too. So far I've only replaced the plugs, wires, cap & rotor. I have not noticed much of an increase in mpg although the truck seems to run better... I'll see what happens after the timing adjust ment.

Somery

what did you gap the plugs to? I hope you weren't expecting to turn your 302 into a 351. There was a poster before that said the same initially, but came back later to say he did notice the improved throttle response and that acceleration was improved. I do believe he mentioned the computer relearning new settings was a factor. 600 miles all in one trip?

Ricky B

The plugs should get gapped to .055, the wires need to be good quality (NO Bosch's. Ever) and at least 8.8mm, if not 9mm. The coil needs to be the MSD #8227 or it's equivalent. The 'Magic' timing number of 13.5 BTDC is really just a guideline, as all engines are different. Mine ended up at about 13.8 (if my timing mark pointer and harmonic balancer's positions are to be trusted) but I actually timed mine not from the gun, but with my vacuum gauge. I'm showing just a hair under 19hg's at an idle of 825--840rpms. And then I trialed and errored it on some test drives. Took me three times before I liked what it did and how it ran. Then the next day we did an L.A.---> San Diego r/trip and I saw my mpg's go up from 14-ish to 17.8, or about 20%.

Don't get frustrated just yet...just take your time, do all of your test runs on the exact same routes and keep adjusting your timing......a tiny bit at a time.

One more tip-----you can NOT have any vacuum leaks. None, zero, zilchito..........


Good luck,

RB

chelios

seafoam the combustion chambers so that chance of ping goes down and possibility for further bumped timing.

J.A.C

If you only getting 13.5 MPG something its wrong . you should get more than that even before you do the upgrade, I getting about 16MPG city and about 18MPG freeway on my old 93- 5.0 with more than 375k miles on engine. everthing stock. still original coil and you should see how bad ditributor cap a nd rotor are right now, the only thigs i have done its E-fans and transm. cooler.

chelios

yeah, a really nicely equipped engine won't be able to perform if there are any problems. check codes and see if any relate to performance. fix all and clear codes again.

enasnitsi

I have zero codes and I have no vacuum leaks. The 600 miles was obviously not on one trip. I went through 4 tanks. This is all on the exact same driving everyday. I gapped the plugs at .055 and I used that msd coil number and the accel wires are 9mm. I also don't expect to gain any power out of it from this if I wanted that I would have bought the 351. I just would like some better fuel mileage out of this truck.

blade z51

Actually, 13.5 is about what I get too. My truck is the '94 XLT with 5.0 and A/T. That is with all new good quality Plugs, wires, cap & rotor. No timing bump done yet and the plugs are gaped to .044 (per Haynes manual).
BTW, my truck runs very well and appears to be in excellent condition with less that 75K miles on the clock.

J.A.C

My truck its a 93 XLT 5.0 , A/T. still runs great, original engine, this it my third transm. and secon rear end. spark plugs 2 years old, wires about 3 years old, coil still original, distributor cap and rotor about 2 years old. thats what im getting now for MPG 16-18 , thats why im thinking 13.5 MPG its too low after the upgrade.