Maximum Timing For Stock Engine

[S Phinney]

It does but the original question is how much is the max % of timing i can safely apply to a stock engine

Maximum timing is going to be relative to rpm and pulse. I am normally 45 to 50 max at say 3250 rpm and full pulse. One person already commented I am wrong. Let's see what his advice is then. I don't jniw everything for sure but have not had a single issue with that timing scenario. You are going to find very limited pointers on tuning.

[2007 5.9]

Maximum timing is going to be relative to rpm and pulse. I am normally 45 to 50 max at say 3250 rpm and full pulse. One person already commented I am wrong. Let's see what his advice is then. I don't jniw everything for sure but have not had a single issue with that timing scenario. You are going to find very limited pointers on tuning.

Perhaps you should re-read my comment.

Right/wrong was not assigned....

If you want help...its best to give specific data in which your asking help with.

Your 1/2 way there with a 3250rpm window....as "Full Pulse" isint a useful datapoint in which to enter into a calculator....

[2007 5.9]

As for the "Very Limited Pointers"...most have spent hundreds of hours, if not thousands on getting tuning right....

Simply asking what is safe, isint going to render a useful answer as the info you ask for is again retaliative to the values your specifically using in your specific application...there is no "One size fits all" when it comes to timing...

[S Phinney]

Perhaps you should re-read my comment.

Right/wrong was not assigned....

If you want help...its best to give specific data in which your asking help with.

Your 1/2 way there with a 3250rpm window....as "Full Pulse" isint a useful datapoint in which to enter into a calculator....

The op had a specific question of what is the maximum percentage of timing to safely run?

[S Phinney]

As for the "Very Limited Pointers"...most have spent hundreds of hours, if not thousands on getting tuning right....

Simply asking what is safe, isint going to render a useful answer as the info you ask for is again retaliative to the values your specifically using in your specific application...there is no "One size fits all" when it comes to timing...

One size fits all surely doesn't work. It is a varying timing percentage. The term safe is also relative to many variables.

[2007 5.9]

The op had a specific question of what is the maximum percentage of timing to safely run?

Without data like rpm and pulse...there is not a answer to give.

[2007 5.9]

Lets use this for example....most people would pick a max of say 30* of timing to run on any given "Stock" application...and lets say that person went with the standard 3200uS "Max Effort" pulsewidth, and their RPM swing was from 2600-3500rpm...this is how a 50% split would look....

RPM US ATDC BTDC
2600 3200 25 -24.92
2800 3200 27 -26.76
3000 3200 29 -28.60
3200 3200 31.5 -29.94
3500 3200 37.2 -30.00


Now running much past 30*ATDC is not going to produce any power, simply heat...which too much heat over time will infact start to erode the bowl lip and cause deformation.

So as you can see that once you get close to pushing RPM, the importance of proper timing becomes very easy to see...

Most tuners would never touch 30*ATDC in any application.

[KhakiCummins]

Lets use this for example....most people would pick a max of say 30* of timing to run on any given "Stock" application...and lets say that person went with the standard 3200uS "Max Effort" pulsewidth, and their RPM swing was from 2600-3500rpm...this is how a 50% split would look....

RPM US ATDC BTDC
2600 3200 25 -24.92
2800 3200 27 -26.76
3000 3200 29 -28.60
3200 3200 31.5 -29.94
3500 3200 37.2 -30.00


Now running much past 30*ATDC is not going to produce any power, simply heat...which too much heat over time will infact start to erode the bowl lip and cause deformation.

So as you can see that once you get close to pushing RPM, the importance of proper timing becomes very easy to see...

Most tuners would never touch 30*ATDC in any application.

Not to thread jack but Les, in the example you gave, is 3200 US just too much pulse to run above 3200 RPM because that is going to put you out of the bowl on both the leading and trailer edge? Is this the point where you would want to step up to larger injectors (assuming you have the other supporting hardware) so that you can shorten your pulse back so that you stay within that +/- 30° window?

[2007 5.9]

Not to thread jack but Les, in the example you gave, is 3200 US just too much pulse to run above 3200 RPM because that is going to put you out of the bowl on both the leading and trailer edge? Is this the point where you would want to step up to larger injectors (assuming you have the other supporting hardware) so that you can shorten your pulse back so that you stay within that +/- 30° window?

FWIW I have never and will never suggest anything over 3000uS as a safe pulse to run...in my production environment, I generally don't go over 2900uS...if i have to use that to hit a target HP, I tell the customer to buy bigger injectors.

As you can see as the RPM increases the injection window decreases...for a stock RPM truck its ok...but start getting into the 3500, 4000, 5000, and 6000rpm areas and man....the window gets VERY small.

And there is no reason to stick to 30* as a max...in fact most high performance tunes I build are in excess of 30* over xxxxRPM...

For a small reference, my personal truck...1000hp single turbo...2300uS max pulse...runs 35*@3500rpm and goes up from there..Im in the mid 40's over 4000rpm

[KhakiCummins]

Thanks for the reply Les. I know that there are a ton of variables and different situations but I was looking at it from more of a general theory perspective to better understand what some of the indicators are for a street truck as to when I should look at bigger injectors. If I ever get to that point.