How much timing on blown 5.0?

[Wicked]

Hey guys,
Especially Lee.
My friend Stephen will be installing his Procharger in the near future.
He has the MSD 6BTM off my old stang and will be using it to retard the timing.

What kind of timing are aluminum headed 5.0's running with say 9-10psi of boost?

Thanks.

[Sendero]

I am just going to throw a guess out there. Just a guess to see if I am learning anything, I am going to say 18* total.

[Wicked]

I'm not sure what the total timing normally is, but assuming with a 10* the max will be 36-38. I figure pull 2 degrees per pound of boost will give me approx. 20 at max boost os 9 psi. Timing might still be higher at lower rpms cause i'm not sure where max timing advanced is added.

[Italian LX]

I'm not sure what the total timing normally is, but assuming with a 10* the max will be 36-38.
At WOT!?!. . .not even close. Stock A9L ecu has WOT timing at 22* at 2250 RPM and peaks out at 26* at 5000 RPM.

You should only be seeing 36-40* during part-throttle cruising.

I figure pull 2 degrees per pound of boost will give me approx. 20 at max boost os 9 psi. Timing might still be higher at lower rpms cause i'm not sure where max timing advanced is added.
How are you planning on pulling timing? You do know that setting base timing different from stock will not change your WOT timing curve, right? You'll have to change WOT total timing through a chip or some other type of ECU management.

[Wicked]

You do know that setting base timing different from stock will not change your WOT timing curve, right?

Now that goes against everything every mustang owner has ever been taught.

So you're saying that all this time that people have been advancing their base timing, it hasn't been affecting their WOT total timing?
:shrug:

:meth:



And we're pulling timing with a MSD 6BTM.

[Italian LX]

Now that goes against everything every mustang owner has ever been taught.

So you're saying that all this time that people have been advancing their base timing, it hasn't been affecting their WOT total timing?
:shrug:
I could be mistaken, but I do believe I read someplace where this is true (and I remember thinking the exact same thing your thinking now). I know that when I increased my WOT timing table a couple weeks ago, I watched my datalogs and they reflected the exact number I put in... even though I currently have my base timing set at 14*. I guess it could be that my pointer is bent and off that far, but I wouldn't think it was off that bad. I'll try to do a couple of WOT datalogs tomorrow and change nothing but the base timing (with the distributor) and post the results.

[QWKSNKE]

I am just going to throw a guess out there. Just a guess to see if I am learning anything, I am going to say 18* total.


Good guess Nathan but it does depend if this is a intercooled system.

I run my 14psi intercooled car at 20 degrees total from 4000 rpm up. If this is an intercooled Procharger system at 10 psi (and it actually sees that) I would recommend the same.

If it is non intercooled I would run around 14-16 total timing.

[Wicked]

I could be mistaken, but I do believe I read someplace where this is true (and I remember thinking the exact same thing your thinking now). I know that when I increased my WOT timing table a couple weeks ago, I watched my datalogs and they reflected the exact number I put in... even though I currently have my base timing set at 14*. I guess it could be that my pointer is bent and off that far, but I wouldn't think it was off that bad. I'll try to do a couple of WOT datalogs tomorrow and change nothing but the base timing (with the distributor) and post the results.

Would it be different with you using tweecer? I wouldn't think so.
I gained power myself on the dyno with my 89 by going from 10 to 14, so I know it is changing the WOT timing. I would be interested in seeing your datalogs, but wouldn't your datalog only show the advance? What I mean is, wouldn't you still have to add the base to get the total timing?

Thanks Lee for the info, and yes it is 3-core intercooled.

So if Brian's 26 is adance, and we run 10 degree base, our total will be 36. So with 2 degrees pulled per psi, we will get about 20 at redline.

We will probably "calibrate" the boost retard so we can knowingly use partial degrees of retard. The boost retard knob is a potentiometer with 1,2, and 3 numbered, but you could be anywhere in between those numbers.

[QWKSNKE]

So if Brian's 26 is adance, and we run 10 degree base, our total will be 36. So with 2 degrees pulled per psi, we will get about 20 at redline.

We will probably "calibrate" the boost retard so we can knowingly use partial degrees of retard. The boost retard knob is a potentiometer with 1,2, and 3 numbered, but you could be anywhere in between those numbers.



No. 26 is total. That is figured on on the 10 degree base and addition of 16 degrees in the computer. Stock 5 liter would detonate like hell at 36 degrees total.

[Sendero]

Now that goes against everything every mustang owner has ever been taught.


What Brian is saying makes sense because all EEC's try to target a certain timing, layed out in their tables, no matter the base timing. This is due to the spark_base_table and spark_bdln_table (EEC-V) because no matter the base timing, that is the maximum allowable spark for a given RPM and Load. The only place that base timing helps is with adders, such as the ACT or ECT.

Here is a good thread (http://tweecer.oplnk.net/viewtopic.php?t=4220&highlight=spark+tables) on spark tables.

[Wicked]

What Brian is saying makes sense because all EEC's try to target a certain timing, layed out in their tables, no matter the base timing. This is due to the spark_base_table and spark_bdln_table (EEC-V) because no matter the base timing, that is the maximum allowable spark for a given RPM and Load. The only place that base timing helps is with adders, such as the ACT or ECT.

Here is a good thread (http://tweecer.oplnk.net/viewtopic.php?t=4220&highlight=spark+tables) on spark tables.

Thats bullshit, as I said before, base timing advance changes everything.

Lee, so if the 26 is max overall, adjusting base means you will reach the max of 26 sooner in the rpm band? So then we only need to pull 1 degree or less per pound of boost to have 20 degrees max?

P.S. Lee, I ran 20 degree base on my 89 with 93 octane before the rebuild. I still had 160-170psi static compression and at 20 * no pinging. After my rebuild I had 195-200psi static comp. and only ran 15-16 degrees of timing.
My point is, 20 degree base plus your 16* is 36 total.

[Italian LX]

I would be interested in seeing your datalogs, but wouldn't your datalog only show the advance? What I mean is, wouldn't you still have to add the base to get the total timing?
Nope, the datalog shows total timing. It sits right at 40* while cruising down the interstate. If that were only indicating the timing advance than I would be cruising to the tune of 54* timing! :confused:

[Wicked]

Nope, the datalog shows total timing. It sits right at 40* while cruising down the interstate. If that were only indicating the timing advance than I would be cruising to the tune of 54* timing! :confused:

I guess I'm confused, how does it possibly know the base timing since it has no idea where the dizzy is in relation to the crank?

[Wicked]

No. 26 is total. That is figured on on the 10 degree base and addition of 16 degrees in the computer. Stock 5 liter would detonate like hell at 36 degrees total.

So if the 26 is including the 10 degree factory base, then by changing the base you change the total correct? Although it wont show up in the datalogs because it has no idea where you have moved the base timing to.

[Italian LX]

Although it wont show up in the datalogs because it has no idea where you have moved the base timing to.
Yeah, I guess the timing in the datalogs must be just what the EEC is commanding, so I was wrong in my assumption. :(

. . . maybe Clint can come on here and clear this timing crap up. ;)

[Sendero]

Thats bullshit, as I said before, base timing advance changes everything.

Ok, go out to the car and turn the distributor without pulling the spout connector if you don't believe the EEC can control the timing. :rolleyes:

I AM saying, that you have two or three tables that control timing, if you advance or retard timing, its still going to try and target a set timing.

Sidenote: My experience is based off of EEC-V's with knock sensors. No matter what I set my base timing too (because I dont have distributor its a software setting) the car takes the lessor of three calculations made on each individual table.

[Wicked]

Ok, go out to the car and turn the distributor without pulling the spout connector if you don't believe the EEC can control the timing. :rolleyes:

I AM saying, that you have two or three tables that control timing, if you advance or retard timing, its still going to try and target a set timing.

Sidenote: My experience is based off of EEC-V's with knock sensors. No matter what I set my base timing too (because I dont have distributor its a software setting) the car takes the lessor of three calculations made on each individual table.

I never said the EEC didn't control timing, but being able to adjust the distributor allows you to adjust the base(and therefore total) and the computer only controls advance per given conditions.

You're also basing your experience off a car with crankshaft position sensor. 5.0's do not have one. They only have the hall effect sensor in the dizzy housing. But since you can adjust that, there's no way for the computer to know actual total timing unless it makes a base timing assumption.

[Wicked]

Yeah, I guess the timing in the datalogs must be just what the EEC is commanding, so I was wrong in my assumption. :(

. . . maybe Clint can come on here and clear this timing crap up. ;)

Are you being sarcastic? I'm just trying to learn and make sure we're all on the same page. :shrug:

I was wondering where Clint was. I found some old Corral post of his when i was looking for info.

[QWKSNKE]

P.S. Lee, I ran 20 degree base on my 89 with 93 octane before the rebuild. I still had 160-170psi static compression and at 20 * no pinging. After my rebuild I had 195-200psi static comp. and only ran 15-16 degrees of timing.
My point is, 20 degree base plus your 16* is 36 total.


yes you are right if your base is 20, then 36 would be total timing as result.

As far as running that much in your 89, this with the stock cam or the 'E' cam you installed. Aftermarket cams will allow you to run more aggressive timing.

[86GT]

The A9L series assumes that the base timing is set to 10°. The timing in the tables has the 10° included. What you see in the logs is what the actual timing is.

If you advance the timing at the distributor pass 10° then the tables will not reflect the correct amount. You will have to add the amount above 10° in you head to each of the cells in the table. It is best to leave the distributor at 10° and just tune the tables. This is so you have a 1 to 1 ratio on the tables.

[Italian LX]

The A9L series assumes that the base timing is set to 10°. The timing in the tables has the 10° included. What you see in the logs is what the actual timing is.

If you advance the timing at the distributor pass 10° then the tables will not reflect the correct amount. You will have to add the amount above 10° in you head to each of the cells in the table. It is best to leave the distributor at 10° and just tune the tables. This is so you have a 1 to 1 ratio on the tables.
Thanks for clearing that up, Clint. :nice:

I wish I could find that thread that I had read that stated otherwise. I don't normally believe everything I read, but I guess it made sense that the timing displayed was what the EEC sees; it didn't even occur to me (until Brad pointed it out) that the EEC has no way of measuring timing advance on my car -- it can only tell you what it is commanding.


. . . I guess it's safe to say that my car will do fine with 38* total @ WOT. :D

[86GT]

It does have a way to read the advance. The hall effect device in the distributor is its feedback. I dont thing ford used it for feedback though.

[Italian LX]

It does have a way to read the advance. The hall effect device in the distributor is its feedback. I dont thing ford used it for feedback though.
Yeah, but without a crank sensor, it would only know the timing from a base reference point; which would be 10* in this case, right?

[86GT]

That is true

[Wicked]

yes you are right if your base is 20, then 36 would be total timing as result.

As far as running that much in your 89, this with the stock cam or the 'E' cam you installed. Aftermarket cams will allow you to run more aggressive timing.

Lee, that was a nearly stock motor. Basicallly the only mods at that time were the free mods, cold air intake, headers, gears. Stock cam.

[Wicked]

That is true

I think technically you'd need a crank trigger to compare against the hall effect output to calculate total timing.

Thanks for the clarification Clint.

[86GT]

Both are true, the EEC has no way of knowing the initial setting. There is a parameter in the EEC that tells the EEC what the initial timing is. I wish I had the address for it. Most all ford EEC's have an initial 10 degrres setting. I believe the probe is an exception.