2056 Timing, Looking for Analysis Of New Timing Values Options

[Mblizzard]

I have converted my 2.0 to a 2056 and added Micro Squirt fuel injection.

Ever since I did the 2056 conversion I have seen higher than norm cylinder head temperatures. In fact I cracked a set of heads from getting them too hot.

I played around with the timing with in the suggested 2.0 limits of around 27 degrees. but was really never able to influence the CHTs that much with changes in the timing. Adding more fuel at the right times with the Micro Squirt certainly allowed me to control the CHT much better but I always felt it was still getting too high.

Then I ran across this.



This is certainly a lot more advance than I ever added to the engine. So based on that I revised my timing table to:



Just love how easy it is to make changes with Micro Squirt.

So I am looking to see what the thoughts are on 35 degrees of advance and what impacts it may have on CHT. I am going to load this and test tomorrow.

[JamesM]

Mike,
Is there specific RPM/Load point on your map where you notice the overheating the most? If so what what is the range (RPM and load) and what do your advance and AFR numbers currently look like there? What RPM range are you normally cruising at?

Curious where that recommended advance cure you posted came from as I have not seen number like that suggested before for a type 4 (though i have for a type 1). The timing table I use was based on a compilation of previously shared data (most of it dyno testing from Jake Raby) that shows you want full advance to come in by 3000 RPM and that max advance is best right around 28deg. Based on what I run the table you posted is slightly retarded from idle pretty much all the way to 4k RPM which i suspect may cause you to run slightly hotter.

Also, what sort of head temps are we talking here? As I recall you mentioned you are running a stock cam and those are known to just run hot. I have a perfectly tuned (passes emissions every time) stock cam 2.0L car that usually runs in the 350-380 range but under extended periods of load can get near the low 400s where as my warmed over 2056 megasquirt car with modified cam rarely even sees 350. I would expect a stock cam 2056 would be pushing near 400 pretty often even when dialed in. Not sure there is much you will be able to do about it other than change the cam.

Ill go grab the timing map off my laptop and post it here in a bit.

I have converted my 2.0 to a 2056 and added Micro Squirt fuel injection.

Ever since I did the 2056 conversion I have seen higher than norm cylinder head temperatures. In fact I cracked a set of heads from getting them too hot.

I played around with the timing with in the suggested 2.0 limits of around 27 degrees. but was really never able to influence the CHTs that much with changes in the timing. Adding more fuel at the right times with the Micro Squirt certainly allowed me to control the CHT much better but I always felt it was still getting too high.

Then I ran across this.



This is certainly a lot more advance than I ever added to the engine. So based on that I revised my timing table to:



Just love how easy it is to make changes with Micro Squirt.

So I am looking to see what the thoughts are on 35 degrees of advance and what impacts it may have on CHT. I am going to load this and test tomorrow.

[Mblizzard]

Mike,
Is there specific RPM/Load point on your map where you notice the overheating the most? If so what what is the range (RPM and load) and what do your advance and AFR numbers currently look like there? What RPM range are you normally cruising at?

Curious where that recommended advance cure you posted came from as I have not seen number like that suggested before for a type 4 (though i have for a type 1). The timing table I use was based on a compilation of previously shared data (most of it dyno testing from Jake Raby) that shows you want full advance to come in by 3000 RPM and that max advance is best right around 28deg. Based on what I run the table you posted is slightly retarded from idle pretty much all the way to 4k RPM which i suspect may cause you to run slightly hotter.

Also, what sort of head temps are we talking here? As I recall you mentioned you are running a stock cam and those are known to just run hot. I have a perfectly tuned (passes emissions every time) stock cam 2.0L car that usually runs in the 350-380 range but under extended periods of load can get near the low 400s where as my warmed over 2056 megasquirt car with modified cam rarely even sees 350. I would expect a stock cam 2056 would be pushing near 400 pretty often even when dialed in. Not sure there is much you will be able to do about it other than change the cam.

Ill go grab the timing map off my laptop and post it here in a bit.

I have converted my 2.0 to a 2056 and added Micro Squirt fuel injection.

Ever since I did the 2056 conversion I have seen higher than norm cylinder head temperatures. In fact I cracked a set of heads from getting them too hot.

I played around with the timing with in the suggested 2.0 limits of around 27 degrees. but was really never able to influence the CHTs that much with changes in the timing. Adding more fuel at the right times with the Micro Squirt certainly allowed me to control the CHT much better but I always felt it was still getting too high.

Then I ran across this.



This is certainly a lot more advance than I ever added to the engine. So based on that I revised my timing table to:



Just love how easy it is to make changes with Micro Squirt.

So I am looking to see what the thoughts are on 35 degrees of advance and what impacts it may have on CHT. I am going to load this and test tomorrow.

I found this is a couple of different locations that I will track down the sources. But this is another one of them that specifically references the Type 4.



I got no attachment to this table and like you it was something well outside of what I knew about the Type 4.

I was previously running your table. At highway speeds 70+ the engine always ran at 350 or higher unless the AFR was set in the 12s. Under load going up a hill temps could reach 400.

Pretty sure the cooler winter temps have a huge impact on the temps that have nothing to do with the timing change. But with the new table they seem to stay in the 360 range on the hill climbs on my standard route to work. Change it to summer temps and I am betting I see similar temps or higher with the new table.

I am like you moving toward the cam as the issue.