I was just wondering how much total timing everyone is running? I posted this on the TPI board, but have not gotten a very good response. I am running 13 deg base plus 30 deg advance according to Tech1, for a total of 43. With no knock retard.

Thanks
nick

NObody knows how much timing they are running? Or does nobody want to share this information? I am just curious for tuming information what everyone has had success with. I was always under the impression that you wanted to run as much timing as possible with knock. right on the ragged edge.
Am I wrong about this?

Does anyone have any ideas?

thanks nick

You want to run thye least amount of timing with the most power. Not the most timing with no knock. (i think bruce says it just liek that)

As for that, every car is going to like differetn amounts of sprk advance depending on mods and what not.

I was trying to say that, the most timing, just before you get knock is where max power would be. I realize every engine is going to be different, but there has to be a lot of guys still running stock iron L98 heads. With a few mods, I just wanted to see what other people have had good luck with.

thanks again guys
nick

OK, he answered your question but you didn't understand him or you don't believe him. You run the proper amount of timing consistent with the best performance at WOT. You run the proper amount of timing consistent with the best drivability at part throttle, cruise and idle. Not til it knocks and then back it off. If it runs best with knock I would say there is some sort of mechanical problem. You don't want to mess with the distributor timing. Set the factory base timing and leave it at that and make changes with the prom. By adding 5* of base timing you add it everywhere so where you might need more at idle you may not need more at WOT. If the Tech 1 shows 30* advance, that's what the total timing is. However, since you added 5* over base timing (assuming your base timing is supposed to be 8*) then you have to add that 5* over base timing to whatever the scanner is reporting unless you changed the base timing in the prom. So no, you aren't running 43* of timing but 35* instead, unless you changed the base timing in the prom.

And every combination is going to want different timing. A general statement would be that old style heads with big cams and low compression are going to want lots of timing everywhere. Likewise, modern efficient combustion chambered heads with high compression and a tight cam are going to want less timing everywhere. But can you really take anything from those general statements?

No he did not answer my question, My question was "How much total timing is everyone running?" And he never did mention how much he is running. Though I thank him for his reply.

Know hector you are saying that the computer knows how much base timing the engine has? Atleast the factory setting? I thought the computer was unaware of base engine timing. Please continue to correct me if I am wrong. I understand about best timing for performance, but I am not going to go to a dyno, for quite a while. And I am not burning proms yet. So all I can adjust right know is base timing. Currently set at 13 deg. I have run this much timing for quite a while and just wanted to see what everyone else is running.

It just seems that enough people have run the same combination that I am running right know that they could send me in the right direction. Obviously I do not care about timing on old low compression motors. My question is for modern day L98's, with stock iron heads.

thanks again guys
nick

The prom has a value placed in it for the base timing. If you mechanically change the base timing and don't change the value in the prom then whatever a scanner reports is not true. Take a timing lamp and see for yourself. As far as what is everyone running for timing, lets say someone gave you their timing table. What would you do with it? If you aren't burning proms then you can't actually make changes to your timing table, so your question is irrelevant. If you add timing mechanically you are just bumping the timing table up by whatever number. The reason you may not have encountered any knock yet is probably due to timing chain stretch. That is probably also the reason why it seems to run better. Do a search on this forum with the keyword "timing" and do some research. I remember a few guys posting their timing tables. Please don't read any attitude into this post. I'm not flaming you or trying to disprove you, I'm just saying what's what. With some research you'll have more than one opinion.

Well the timing chain is brand new. And I appreciate your help, I do not want a n entire timing table. I am just looking for the maximum total timing people are running, thats all. Just so that I can confirm that I am in the right ballpark with my timing right now. I understand that you need different timing at different rpm and throttle position. I am just looking for a total timing number, to see how I compare. What people are running for base timing and what kind of advance at WOT. Thanks for the input.

nick

I'm running 17d advance at WOT.

But, it doesn't make much sense does it?.

Without you mentioning what your combination is, any numbers are meaningless.

There is no reason to running your timing anywhere near 43d.

You can run soooo rich at WOT to prevent detonation, but still eat up the top of the pistons. And knock out the rod bearings.

My combination is in my first post in my signature?

So you are only running 17 deg of total timing?

thank you for the response grumpy, it is greatly appreciated!


nick

Sorry to be a bad guy, but this post really doesn't have anything to do with PROM burning. So, I am moving it to Tech/General where it will get more of a response.

Also, you do realize that on 6Es, the total spark advance already has 6* built into it for the base...so you need to account for that.

Thats not being a bad guy glenn, I just thought I would get more responses in the DIY prom board. Since I know that guys in this board should know how much timing they are running.

Another question Glenn, and I think hector said the same thing, that when I am reading a 30 deg advance on tech1, I am really only getting 24 deg, assuming a 6 deg programmed advance?

Now I did some checking today with a timing light and Tech1 combined. My base timing is 12 deg, at idle Tech1 was showing 10 deg of advance. And it sure looked like I was getting 22 deg of advance according to the timing light. I am going to try to locate a better timing light to confirm this. But if you guys are saying that 6 deg is already programmed in, it should have 16 deg of advance on the timing light. And it was definitly past that.

Once again thanks for the help guys, please keep correcting me

nick

OK, then what heads are those, material wise, and what cc chamber?.

Less then 26d will be too low generally, more then 34 is really rare. While lots of folks like to run on about how much timing they run, to me, the trick is running as little as possible.

In the old days people thought you advanced the distributor until the engine pinged under load then backed it off a bit. This does not produce the most power.

Determining what the best total timing for "your" engine is a guessing game. The best thing to do is put the car on a dyno and adjust the timing on each pull. Many cars that don't knock or ping at 38-41 degrees actually make more power in the 34-36 range.

You can do a dragstrip tune also. Adjust your timing 2 degrees at a time and watch your 1/4 mile mph. If you increased the timing and the mph dropped then go the other way.

My distributor has no mechanical advance. Timing is locked at 36 degrees. The ignition has a start retard so I can start it but it constantly runs at full advance. Race engines don't need a spark curve.

If you adjust your base timing then your total timing also changes. If you run an older style HEI (coil in cap) you can play around with the weights to adjust the amount of mechanical advance.

I'm running, 6* base and 28*in a modified arap chip. I'm still trying to get it better. How many spark counts are you getting? With a stock chip and 12* base, I think the computer has to be pulling out timing. Even if you can't hear it knock. I was from the old school too, put as much as you can. It's gotta help, WRONG. Without a logging type scanning program you may not even be able to tell it's pulling out timing.

32-38 degrees is about typical. I have mine at 36 at the moment.

37 total. To get it perfect you need to run back to back to back.... on the drag strip or use a dyno for max power.

Thanks for the replys everyone, it is greatly appreciated!


Grumpy, cast iron L98 heads, 64 cc, milled 10 thousandths.


thanks

nick