Soaring may not know diddly but at least he can spell diddly! I can't seem to.

 

Only if your damper is 100% accurate. They slip when they get a little too old... In any case, the timing marks should be used as a good starting point. The actual timing you run will be based on the quality of gas, temperature, atmospheric pressure, etc.

 

Well............not according to late model fi cars that had what was reffered to as an 'octane appitite increase' as they aged by milage. BMW conducted extensive tests and proved that carbon build-up on the intake valve absorbed fuel, caused an over lean mix that resulted in detonation which in turn caused the owner to use progressivly higher levels of octane.

I don't think too lean is his problem, not on a stock engine with an aftermarket carb...most of those are set rich for stock motors without headers. I think his motor is clogged with carbon or his distributor is set with too much vacum advance (which is also adjustable on his Mallory).

 

If it's clogged with carbon, spraying water into the carb with the rpm's high will blow that crap out.

 

Pinging is also caused by high compression...which is what carbon build up does. It can be curbed with a reduction in timing...or by cleaning out the carbon.

Of course, having your engine tuned properly, quality gas, and quality oil will keep carbon from building up in the first place...

 

Wow, for all the experts we have, I'm suprised no one suggested this:

If the pinging occurs at "partial" throttle, especially on a small grade, where the engine is just starting to "work" a little, it's the vacuum advance coming it a little too much or a little too soon. A variable vacuum cannister will solve your problem for just a few bucks - and maybe you've already got one! If you do, just find a hex wrench that will "engage" through the opening with the vacuum hose off. if you can "connect" pop the lid off the distributor and watch the advance mechanism, if it moves as you crank on the vacuum "adjust" you are home free. The only way to get it "right" is to start with it at "max advance" I think this is all the way "in" (righty tighty). Go back to that hill/situation where it pinged. With max advance, it will probably be worse. Pull over, pull the vacuum line and start backing the adjust screw out... now go back to the same hill same speed and see what happens. You want to back off the timing JUST ENOUGH TO STOP THE PINGING.

As for the carb stuff, I had just the opposite experience - I spent MONTHS trying to eliminate a "bog" on a holley - bought the tuning kit, changed cams, jets, linkage holes, springs, power valves, nothing worked. Bought a performer 500CFM with electric choke and was happy right away. It came WAAAY rich from the factory, but a couple set of rods let me lean it out till it was TOO lean (hesitated on transition from mild to wild) so I knew I had gone to far. Best part of all is that as I was LEANING it out, I got better mileage AND more power! (The chemistry guys can explain this...). I am now a happy camper. I had to take it apart only once in the last 5 years, to clean out some crap cause I didn't have an inline gas filter. NOW, I have one!

 

alright well I am back in school tomorrow and I'll talk to my teacher about getting my hands on some books to help me know exactly how to do all of this (basic timing and parts instillation I know, its the fine tuning and adjusting from base settings I don't know)... At least I have something to take up the small amount of spare time I have between Church, Work, and School...

I do know that it doesn't matter what tooth I get it on as long as I am able to get it to the timing I need.... (but yes I got it back on the exact same tooth that I took the old one off of...

I probably wont have time (ha ha timing problem, get it?) to get to it until Tuesday or Wednesday so ill let you guys know what I find out...

 

You obviously DID NOT read my posts. And the more lean made more power and got better mpg.....looks as though you young guys have not heard the expression 'lean-best-power'...reffering to going lean until you see a power drop....go 1 or 2 more steps lean and you hole a piston. But what is hapening is as you go lean you also go hotter on combustion temps which also increases cylinder pressures and you see a corresponding increase in torque/hp. Think of a blast furnace where you force more O2 to rainse the heat in the furnace. Just don't force too much.

 

Ok so I figured it out FINALLY... and we all get to be right on this one (kinda)..
I have not tuned the ignition system or the carb properly yet however I have gotten rid of the ping.... which was a combination of a lean gas mixture and retarded timing. However this is where it gets confusing, The base timing was set at 6 deg BTDC (manufactures specification) and then the mechanical advance max was about 25more, and the vacuum advance took another 35ish advance... and I played around with the timing thinking that the mec and vacuum advance was to much and we finally found that with the vacuum advance and mechanical advance we had to set the base timing to about 13-15 deg BTDC.... is it just me or is that kinda high? to have a max advance of like 75?
second thing was I set my carb back to stock while I was doing this then once we got rid of the ping I leaned it out again and it came back a little but not much and so I have been playing around with the metering rods and jets that I have for it to see how lean I can get it without having to go back to stock.... (I like to save as much gas as I can with this gas sucking beast of a car).... so who wants to be the first to tell me that I am a moron and I am going to blow up my engine with what I am doing?.... so now that we have fixed that problem what do I tune first Ignition or carb? and I have a nice link to help me tune my carb but I do not have any idea of how to tune my distributor so any help would be great.... here is a link to the distributor I bought http://store.summitracing.com/partde...p;autoview=sku ... its a Mallory unilight electronic ignition with the hall effect (optical) in it.... oh and sorry for the messy post, I didn't have much time to type all of this down neatly and I think sporadically like this as well so that doesn't help, hope I covered all the information well enough for you guys to understand and be able to advise me correctly.

Brian

 

Just for the record. I read every post on this thread and now I am even dumber. I have no clue what any of that means, it might as well been in Latin. Maybe it was and that's why I didn't understand a word. [sm=why.gif]Now I'm going to go have to buy me some books on all this stuff.