1990 302 truck,what is the most you can bump the timing up before you get negitive results?

 

Usually 2-4 degrees is all they will take before pinping becomes audible.

 

so you can keep advancing till it1s starts to ping?what hp gains will you see?and mileage improvements?

 

i would set it around 10* that seems to be their sweet spot, you won't get a bunch of h/p but it'll be noticable

 

Have a 91. Would like to try that too. Didn't see an answer to his question about mileage. Any changes ( up / down )?

 

I have my '97 with a 351 set at 14° and it made a big difference in performance, I didn't notice much difference in MPG though..

Of course mine is a 250HD long bed and deep contractors box in the front of the bed (full), full length side boxes (also full), small air compressor, and a generator in bed ahead of goose neck hitch. It hits the road at about 7200 Lbs with both tanks full of fuel, so good MPG ain't gonna happen around here!!!!!

 

Yes 14 deg should be good 10 deg is stock setting....

 

Sounds like GPM in your case. Just curious what ( if anything ) I could expect from my F-150 W/302. Increase would be great. Am having a complete tune-up, plus all fluids ( except eng. oil, already did that ) flushed & filled. This way I know I'm starting off fresh. Haven't checked it yet, so I don't know what it's getting. Figure it can't hurt & may even help.

 

It helps if I go down hill a lot!!!!!

I have heard it helps MPG some, I am just not sure how much on our trucks, I have a mint 93 T-bird 3.8 V-6 and I did the timing trick on it, I can get around 32 MPG on the interstate with cruise on now, before I played with it I was around 27-28, but this is a whole different game, the bird actually cuts through the air, my truck just pushes it!!!!

 

I've had my timing bumped up to 14 BTDC but didn't notice any difference til i also widened the plug gaps to .55. That's when i got the difference in throttle response.

Autolite coppers, btw.

 

97 XLT, glad you have a sense of humor. Wasn't trying to give you a hard time. Know what you mean about the downhill part. Once owned / drove a 75 LTD 460 4bbl. 4 door. Lead sled +½. Yeah, the Bird also has a couple less cylinders to burn the fuel. Little bit of size difference. 351=5.9? vs. 3.8.To quote good old Homer Simpson, " Duh!! " Not too good on these sillyliter / sillymeter sizes. Guessing on the 351, had a Dodge w/ 360 & think that's what it was. 351 is pretty close in size to that.