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I know this should be TOO MUCH timing, but....

Hey Everyone, last night i was doing a little work on the 5.0 in my 2wd Ranger. Cleaned and re-gapped the plugs, a little tweak on the carb, etc. I bumped my timing a little more, thinking it would probably be too much. I had it around 12 BTDC, before, and i bumped it to 14. Ran a little better, no pinging. Great! maybe a little more? You bet. Bumped it to 16 BTDC. Same result.... a little better accelleration, no pinging. I'm running 89 octane and it's got a Crane cam:

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#444226, headers, Edelbrock intake, stock heads w/ 1.6 rockers. I can't imagine i have the distributor off a tooth, but it is possible. But i also can't imagine running this much timing. When i put on the timing set, i installed the cam "straight up", and triple-checked it. The distributor is for an '85GT, vacuum advance with an MSD ignition box.

Thoughts?

Thanks, Don W

Reply to
Don Wallish
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You're probably running too rich if you can dial in that much advance on 89 octane fuel. How do your plugs look?

-JD

_________________________________ JD's Locally-Famous Mustang Page: http://207.13.104.8/users/jdadams Please note: UCE is deleted at the ISP server level. Unless your address is on my 'accept list', your mail will never reach me. See my website for more information.

Reply to
JD Adams

I was thinking along the same lines. The plugs looked pretty good. Some ash deposits that had me a little concerned, but otherwise okay. No oil and/or fuel anywhere. I was going to pull the plugs after this tank of fuel and see how they look again. The carb is a Holley 600 cfm, been working very well. I adjusted the idle mixture a few months ago. The idle was a bit rich then, now the idle screws are nearly all the way in.

Any more advice would be appreciated!

Thanks, Don W

Reply to
Don Wallish

try 18,20 or more and see how it responds. Did you disconnect the vacuum supply to the distributor when you were checking the timing?

Reply to
winze

Or the engine has had it's compression reduced for some reason.

Ed

Reply to
BiteMe

Ahhhh...good call. It's also possible I suppose, that the distributor advance isn't working properly, or there is a vacuum leak in the advance pot.

-JD

_________________________________ JD's Locally-Famous Mustang Page: http://207.13.104.8/users/jdadams Please note: UCE is deleted at the ISP server level. Unless your address is on my 'accept list', your mail will never reach me. See my website for more information.

Reply to
JD Adams

Hey Guys, I disconnected the vacuum hose and plugged it. Of course something could be wrong with the advance, who knows. The Compression Ratio should still be close to stock. When i rebuilt the engine the heads were re-surfaced, but nothing more. Stock replacement pistons with valve-reliefs. I'll grab the timing light again tomorrow night and bump it a little more and check the plugs again.

Thanks for all the advice, Don W

Reply to
Don Wallish

Have you confirmed TDC with a piston stop? Until you do that the timing marks are little more than reference points to let you know your in the ball park. With your mods 16 degrees advanced is not out of the question. Freshening up the heads and getting rid of carbon deposits (which cause hot spots) can do wonders. Even a slightly larger cam will start to bleed down the cylinder pressure which is like lowering the compression ratio. Cylinder pressure is more important than compression ratio. I had a 351w with 11:1 compression and a small cam that would darn near spark knock at idle, but after swapping in a bigger cam that all went away. One other thing to watch for beside spark knock is an increase in running temp, so keep an eye on the temp gauge as well.

MadDAWG

Reply to
MadDAWG

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