How to retune the block of 8* timing?
Oct 16, 2006, 12:10 PM
#16
Originally Posted by MalibuJack
Well, without being too obvious one way or another..
The issue with knock, is transitions in timing, when you jump to higher load (or drop to lower) and you have a progressive change in timing, you will get large timing jumps which will result in knock even at lower timing values..
Although I try to always tune with transitions, there are always a plateu region where the timing doesnt tend to change much, what this does is allows the ECU to change load columns in large jumps, without large jumps in timing. It just needs to be accompanied by part throttle tuning to get the low load timing in check also..
The issue with knock, is transitions in timing, when you jump to higher load (or drop to lower) and you have a progressive change in timing, you will get large timing jumps which will result in knock even at lower timing values..
Although I try to always tune with transitions, there are always a plateu region where the timing doesnt tend to change much, what this does is allows the ECU to change load columns in large jumps, without large jumps in timing. It just needs to be accompanied by part throttle tuning to get the low load timing in check also..
Oct 16, 2006, 01:11 PM
#20
I can even spot the sea of 8s from datalogs now and I've never been in a car that has been Dynoflashed.
There is only one way to get persistently high knock sums without false knock and that is to have the low octane map useless by being the same or similar to the high octane map. The ECU is aiming to keep the knock sum at 4 or 5.
There is only one way to get persistently high knock sums without false knock and that is to have the low octane map useless by being the same or similar to the high octane map. The ECU is aiming to keep the knock sum at 4 or 5.
Oct 16, 2006, 01:14 PM
#21
Originally Posted by TTP Engineering
It is a good point to note you can hit 4 horizontal cells in 1 rpm increment on spoolup. Any tune should be tapering timing as load increases. If this is the case there should not be increased knocksums. I don't know anyone that tunes with great jumps in timing numbers as load increases so I am unaware of how dramatically dropping ign timing would cause knocksums.
Oct 16, 2006, 01:40 PM
#22
Originally Posted by TTP Engineering
It is a good point to note you can hit 4 horizontal cells in 1 rpm increment on spoolup. Any tune should be tapering timing as load increases. If this is the case there should not be increased knocksums. I don't know anyone that tunes with great jumps in timing numbers as load increases so I am unaware of how dramatically dropping ign timing would cause knocksums.
Anyway, its not the dropping of the timing, but the jump from the low load higher timing, to the higher load low timing when it skips a few columns.. When you have stock timing at no boost to very low boost of numbers much higher than the timing you'd hit under boost, that radical change would result in a timing jump also.
Oct 16, 2006, 02:27 PM
#23
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Originally Posted by JeffR116
The Ambiguity in this thread is hilarious.
Why can't we just say his name?
Why can't we just say his name?
Oct 16, 2006, 04:11 PM
#24
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FWIW I do not have high knock sums with my block/custom flash. In the datalogs I have done I have never seen more than 3 counts. However I am seeing very consistently that with each knock count I loose one degree of timing. This usually occurs as you might expect at peak torque.
That being said I was curious to see the other options of dealing with timing vs. the block of numbers for a given boost setting to push the envelope a bit (not too much of course).
That being said I was curious to see the other options of dealing with timing vs. the block of numbers for a given boost setting to push the envelope a bit (not too much of course).
Oct 16, 2006, 04:29 PM
#26
Originally Posted by broeli
Although I would normally agree, it doesn't seem to have any negative effects on the Evo. I have a base flash with the block of 8's and I'm also using in ECU+. I have had the block of 8's left intact for 3 years now which includes many many days of racing. I'm not talking drag racing either. I'm talking hours and hours of road course racing and autox'ing.
Oct 16, 2006, 04:43 PM
#27
The smoke and mirrors of this all is the ones that do not experience knocksums are <20-21psi and likely too rich for optimum power. Lower boost and richer AFR may allow for higher timing without knocksums at the cost of power.
There is one exception:
I have a stockish 2003 Evo also with drop in, Forge UNOS mbc and custom reflash. You can run higher timing on stockish cars. As soon as you go TBE and can spoolup that turbo 500rpms faster you have to run lower timing.
There is one exception:
I have a stockish 2003 Evo also with drop in, Forge UNOS mbc and custom reflash. You can run higher timing on stockish cars. As soon as you go TBE and can spoolup that turbo 500rpms faster you have to run lower timing.
Oct 16, 2006, 04:54 PM
#29
Originally Posted by TTP Engineering
The smoke and mirrors of this all is the ones that do not experience knocksums are <20-21psi and likely too rich for optimum power. Lower boost and richer AFR may allow for higher timing without knocksums at the cost of power.
There is one exception:
I have a stockish 2003 Evo also with drop in, Forge UNOS mbc and custom reflash. You can run higher timing on stockish cars. As soon as you go TBE and can spoolup that turbo 500rpms faster you have to run lower timing.
There is one exception:
I have a stockish 2003 Evo also with drop in, Forge UNOS mbc and custom reflash. You can run higher timing on stockish cars. As soon as you go TBE and can spoolup that turbo 500rpms faster you have to run lower timing.
Oct 16, 2006, 05:46 PM
#30
i had an e-flash from this particular vendor(8 block)and recently purchased a new map from jestr tuning for 50 bucks and my car is running much better IMO and no 8 blocks! the 8 block should be the least of your concerns though, what really concerned me was how close(mostly just 1* difference)the high and low octane maps were. if the tune is good you shouldn't even be going into the low octane map unless you got bad gas or it's extremely hot or other variables, and mitsu made the low maps safe for a reason, there should be no reason to change them except maybe the low fuel map slightly if your using an aftermarket fuel pump. with a good tune and all other things being normal, your car should only run in the high maps therefore making it unneccessary to change low other than to cover a bad tune.
