what is meant "get all the timing in' @xxxx rpms?
#1
what is meant "get all the timing in' @xxxx rpms?
I presume it is for WOT?
My greatest timing(42) is at low load cells 40-50 MAP 4000-6000 rpms.
My WOT timing at 2000 rpms is 25 and it moves upward incrementally to 33.4 at 4800 and stays there to 6000. Add to that 2 deg for PE in 1st, and 1.75 in 2nd, 1.5 in 3rd, and 1.0 in 4th gear.
A bit more aggressive than Iron LT1 SA Map.
My greatest timing(42) is at low load cells 40-50 MAP 4000-6000 rpms.
My WOT timing at 2000 rpms is 25 and it moves upward incrementally to 33.4 at 4800 and stays there to 6000. Add to that 2 deg for PE in 1st, and 1.75 in 2nd, 1.5 in 3rd, and 1.0 in 4th gear.
A bit more aggressive than Iron LT1 SA Map.
#2
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Car: 91 Camaro RS
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Re: what is meant "get all the timing in' @xxxx rpms?
That generally refers to WOT only, nothing to do with low map/cruise areas. So you are "all in by 4800 rpm".
If I recall correct, you are running vortec heads. So, yes 35.4 total timing is pretty aggressive for vortecs.
If I recall correct, you are running vortec heads. So, yes 35.4 total timing is pretty aggressive for vortecs.
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Re: what is meant "get all the timing in' @xxxx rpms?
ive heard it thrown around alot when talking about mechanical dizzy's, adjusting springs, changing weights, etc. "all in by XXXX rpm's"
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Re: what is meant "get all the timing in' @xxxx rpms?
Timing is much more strongly dependent on cylinder pressure than actual time. But there still is some time effects present. At low RPMs, there is a lot more time for the flame front to progress, so you need less timing. Since the time for cylinder firings is proportional to 1/RPMs, the time differences become much flatter at higher RPMs, so the required SA becomes essentially flat at WOT above around 3600-4000 RPM. Basically then its just a function of cylinder pressure, hence the need for it to just remain at roughly one value, or at the "all in" of 32, 36 degrees, or whatever suites the engine. This is also why race engines can run with their timing locked at one value since its all high RPMs.
The "all in" also applies to P/T as well. Usually in stock calibrations the timing becomes flat at higher RPMs at almost all loads without that much variation. As said above, the "all in" is a term used for mechanical distributors, but applies to the CC units just as well.
The "all in" also applies to P/T as well. Usually in stock calibrations the timing becomes flat at higher RPMs at almost all loads without that much variation. As said above, the "all in" is a term used for mechanical distributors, but applies to the CC units just as well.
#6
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Re: what is meant "get all the timing in' @xxxx rpms?
Also remember peak torque is the highest engine airflow and usually highest ve. Usually wants abit less timing than peak hp but not always. Just something to try but yes, all in by xxxx rpms means having max advance at wot by that rpm and hold flat til redline. Not all combos will want this however
#7
Re: what is meant "get all the timing in' @xxxx rpms?
What BCC (broadcast code) is being used, and are you adding in the main spark table, power enrichment table, and initial to achieve said total?
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Re: what is meant "get all the timing in' @xxxx rpms?
The phrase used to indicate how aggressive a builders timing curve was.
This was a time of mechanical distributors and before we discovered top-end retard.
This was a time of mechanical distributors and before we discovered top-end retard.
#10
Re: what is meant "get all the timing in' @xxxx rpms?
First, I know nothing of Rob's EBL. Total timing under load (WOT) is a combination of main spark table, power enrichment table, and initial. Add all 3 together using consideration mainly for stroke, and a combination of overall displacement. I try and work most anywhere from 32 to 36, but will give as much as 38 to shorter cranks.
#11
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Re: what is meant "get all the timing in' @xxxx rpms?
I usually zero out pe mode advance and work from main table only. That way i see my final numbers and dont have to add. Base timing is already accounted for in main table. From there i give the motor as much advance as it needs to make max power and verify that by dyno and track times while not tripping knock sensor. Different heads like different timing. Afr's new stuff wont take same as afr old heads nor is it the same as RHS for instance lol
Most sbc like 36-38 deg some only 30-34.
Most sbc like 36-38 deg some only 30-34.
#13
Re: what is meant "get all the timing in' @xxxx rpms?
To the best of my knowledge if you set WOT to 30 degrees, and intial at 6 you have a total of 36. The PE is vacuum activated at 90 KPA.
#14
Re: what is meant "get all the timing in' @xxxx rpms?
It may depend on the def file xdf and the datastream ads. EBL includes the initial in main table. Prior I used $42/7747 and it too included initial in main. Same on the SA in data stream. In data stream the PE was included in both.
#15
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Re: what is meant "get all the timing in' @xxxx rpms?
For 6e and 730 using code $59, its always been 6-10 deg initial base timing and same value in the bin file for base timing, then whatever is in main table thats what crank sees at balancer, assuming no other adders and inaccuracies. 34 deg wot at 4800 rpm in table shows 34 at balancer under the light. Again assuming no adders like pe mode as i zero that out and also no retard or advance from coolant temp offsets.
#16
Re: what is meant "get all the timing in' @xxxx rpms?
For 6e and 730 using code $59, its always been 6-10 deg initial base timing and same value in the bin file for base timing, then whatever is in main table thats what crank sees at balancer, assuming no other adders and inaccuracies. 34 deg wot at 4800 rpm in table shows 34 at balancer under the light. Again assuming no adders like pe mode as i zero that out and also no retard or advance from coolant temp offsets.
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