I found this tread: http://www.pirate4x4.com/forum/showt...threadid=23587

One of the guys bought a 3.0 4Runner with timing bumped up to 16 degrees and the power was a LOT better than other 4runners he drove. I believe he said stock timing was 10 degrees. What do you guys think? Will this hurt the engine?

 

Just do it a degree at a time, then roadtest.
Keep bumping it up until you get pinging under full load.
Then back it off one degree.
That will be your max power.

 

If you always run 92 (or 93/94 whatever you can get) you can bump up the timing even more (probably) yes this is a safe mod as long as you never go to lower quality gas than you regularly use (ie if you tune it for 89 DO NOT use 87 octane unless you set the timing back again) You can see quite a bit of power from this mod especially in combination with exhaust and intake mods. (For the money that is hehe)

 

Watch your mileage, too. Every vehicle I've owned I've bumped the timing up one (except the 4Runner). I typically notice a 1-2 mpg increase. My 1.5L Honda reacted really well to it. I gained 5-6 mpg. A highway trip of 130+ miles resulted in 56.2 mpg. That car was great for sipping fuel. And it could go from 0-60 in 2 days!

 

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I run mine advanced to 14 degrees BTDC base timing and it made a huge difference. I dunno how many ponies I freed up but there was no doubt that I was putting out more power throughout the entire RPM range. Most of you 3.0 drivers are prob used to the motor struggling to hit 5500 RPMs when you're on the GO pedal. After I changed my base timing to 14 degrees it hits redline much faster and doesn't pewter out on the way up to redline. I used to own a Taco with a 3.4 and manual tranny. When I got my 89 with a 3.0 I was quite disappointed. I had done all the tune-up items and made sure timing was set to 10 degrees BTDC which I don't think even helped with power output. But, when I bumped the timing and lead footed the go pedal a smile came to my face when I realized that it was almost as fast as the 3.4. I also have .040" O/S pistons, fresh heads and an exhaust. The .040" O/S pistons equate to about another 5 cubic inches which isn't much but when you have a 3.0 anything is a lot better. Knowing the 3.4 puts out 190hp, I would guess that my 3.0 is now putting out 170-180hp. That's assuming the 2nd gen pickups and tacos have the same curb weight too.

 

When I had my '90 SR5 4Runner, I had the timing at 12 deg. and felt a very noticeable difference in towing power. It had minimal impact, if at all, on my fuel consumption other than having to rum midgrade occasionally.