200sx with a Ka24de(t)

[Niclas_AB]

Ok, so i thought I'd share my project and hopefully get som help with my problems.

The car started out as a 200sx with a ca18det engine, I did some BPU to it but wanted something different. I got my hands on a ka24de engine from the US 240sx and decided to do a swap.
From the beginning I was thinking of turbokonverting it with something lika a garret T28 but as usually things got a little out of control.
New pistons and rods where bought to handle som more power and I bought a holset HX55.
Unfortunally there wasn't room enough to keep the distrobutor so I did a coil on plug solution and only use the distrobutor/CAS as CAS.
I replaced the sensor disc with a 24+1 disc, it happends to be the same as the sr20det engine uses.
I removed al of the engine harness/standard ECU and replaced it with VEMS and a V3 harness.
I'm now trying to start it up but I had/got some problems. First I couldn't get it to fire the ignitioncoils properly, that problem turned out to be my MSD DIS 4 unit that had broken down.
So for the moment I'm running the coils directly with VEMS and it looks fine when you have the sparkplugs out of the engine.
I have the engine idling now but only barely, it's so bad I can't even set the spark angle to 0 because it's jumping al over the place(between 0 and 40degrees). If I rev the engine the spark advances. What could be causing this?
I also would like to know if anyone have firmware 1.1.44alpha2 running with the 24+1 trigger?

[rob@vems.co.uk]

Stick with 1.1.18 until you get the timing cleaned up.

How steady is the advance when cranking?

[Niclas_AB]

If I remember correctly it was pretty steady, but I will dubble check it.
What should the "Angular width of tooth" be set to? Right now it's set to 6.00 but I can't really understand why? I think it should be set to either 5 or 10 degrees after looking at your drawing of the triggerwheel?
I'm going to try to upload the .msq and a logfile somewhere.
Thanks for the fast reply

[Niclas_AB]

The spark is consistant when I only crank the engine, the spark angle moves maybe 2degrees at max, so that seem ok.
I also tried adjusting the fuel more and got it to run a little better but if I go any leaner now the engine stalls, spark angle variation was maybe down to 20degrees, but the spark angle was still advancing alot when revving the engine.
//Niclas

[rob@vems.co.uk]

Make sure you havent got the Advance Idle control enabled, that advances and retards like crazy to try and hold the engine RPM on target.   Also you need to start datalogging to analyse what's happening when the engine is running.

[Niclas_AB]

The advanced idle is of, was even worse when it was activated.
I do have a datalogg, just nowhere to put it. But I will fix that today.
I also tried pulling away 1 injector at a time while idling and you couldn't tell any difference at al, so its not tied to any specific cylinder.

[rob@vems.co.uk]

Set the entire idle area on the map to a fixed 17degrees, if the advance is fixed nicely during cranking theres no reason why the VEMS shouldn't keep the advance static when the engine is running.  If the spark advance gauge is jumping all over the place then the ecu is driving it like that.

[Niclas_AB]

Ok, I've finally got help to upload the msq and log, they can be found here:
http://sportscars.kicks-ass.org/mappning/Niclas/

I did notice that the spark angle gauge and the Pulse width gauge sometimes starts to jump when the igntion just is on, is this normal?

[rob@vems.co.uk]

When the engine isnt running I've seen flickering on the PW and Spark dials too - nothing seems to happen so I think its more about the software.  When the engine is idling with that advance what is the timing light showing on the crank trigger mark?

[Niclas_AB]

Well, shows between like 5 and 30 degrees i think, hard to say exactly. But it moves around about that much i think.

[rob@vems.co.uk]

Okay, I think that the problem is mechanical, belt drive cams can have a lot of 'slop' in there and the problem is that the rising and falling revs make the sloppiness worse.

I'm guessing that the KA is belt cam?  If not theres no undue wear on the distributor/CAS is there?
It might be worth checking the condition of the timing drive tensioner.
Worse comes to worse I'd suggest a two tooth Hall crank sensor, and use the single slot on the CAS disk for sync. 

[Niclas_AB]

The ka24de is chain driven. Actually there's two chains, one on top that drives the cams and goes down to about the middle of the engine to a gearwheel. The bottom chain goes between the crankshaft and the gearwheel in in the middle. The CAS is connected to the gearwheel in the middle. I think the CAS is driven in the same way in the sr20det? not sure if that also have dual chains tho? Hope you understod my explanation, not so easy when you don't speak english as native language.

I'm also beginning to think that I have some mechanical troubble, have to tripple check that my cams are set right.
Also did a compressiontest and got about 110psi on al cylinders, not god at al. Don't know If it could take a while for the new pistonrings to seal?

[mattias]

Is there any evidence that someone with a 24+1 trigger is running with 1.1.44 firmware ? Or for that matter any firmware other than 1.1.18?

[rob@vems.co.uk]

I'm hoping that Gunni will have some success with 1.1.44 on that Skyline he's doing at the moment.

[gunni]

We´ll have to see later this summer when I go back as I´m back from 17 long days.

But I´m quite pleased with the 1.1.44 , makes those 12v M20´s run smooth as silk, wasted or single coil.
And that RB25 idled smooth as hell as well. It was able to idle super smooth as low as 450rpm