Nistune Forums

I'm trying to set base timing on my sr20det but I can't get it to 15deg. I installed the cas as per the service manual but when i turn it as far as it will go, the most I can get is about 10deg. I initially thought I must have got it one tooth wrong so I took it out and advanced it one tooth, but now I can't get anything lower than about 23 deg...? The consult is showing 15deg timing when I'm trying this.
Anyone got any thoughts as to why I can't get the timing right???

you need to order the ECU to go into base timing adjustment mode...
for that you need Consult software (datascan and similar), though I think Nistune also does that.
go to Active Tests, Base Timing Adjustment (or something like this), then activate and adjust timing with a proper timing gun and HT lead on cylinder #1

i can't work out how to get it into base timing mode in nistune, in the active tests page you can put a timing offset in, but there is no option to lock the timing that i can find. Anyway, as long as I can get the timing gun to match the consult stream then that should be ok.
It idles nicely with the consult showing 15deg timing, but the gun is showing me either 10deg, or if i take the cas out and advance 1 tooth i can get 23 deg, but I can't get anywhere in between those 2.
Is there any way the CAS gear can move on its shaft? how is it locked to the shaft?

I'm not sure Nistune has that function or not... I do know how to do it in S14's and S13's with the SR20DET engine. as I said, best way is via consult software...

as for the CAS... it connects to the camshaft via a "spiral dented" wheel ... you can remove it and such, but it can become a PITA to refit it properly...

You don't necessarily need to do the Base Idle thing. Just check that the timing figure you see reported by the ECU (in whatever program you want) matches what you see using the timing light.

This figure will vary depending on how well your idle is set up. If everything is good then you'll see 15 degrees. If idle is too high then the ECU may well pull timing back in an attempt to lower idle speed. If idle is too low then ECU will add timing.

Also, don't forget that the SR20 timing marks go (from L to R) 5 ATDC, TDC, 5 BTDC, 10 BTDC, 15 BTDC, 20 BTDC. So you want the second mark from the right.

Sorry if I'm trying to tell ya how to suck eggs here, but a lot of people get this wrong.

PL

i know what your saying, my problem is I can't get the gun timing to match the consult timing....
I can get it to have a perfect idle with consult reporting rock steady 15deg timing with the cas rotated to the end of its adjustment the max gun timing I can get is 10deg.
Or if i advance the cas 1 tooth, I can get a steady idle with consult showing a steady 3deg timing, but the cas is at the end of its adjustment and the gun is showing 23deg.
Its like the gear on the cas shaft has slipped or something, my friends s14 motor sits happily on 15deg timing with the cas right in the middle of its adjustment.

I can see only one big fault.

You should NEVER take the timing gun signal from the coil wires. Doing so is a major chance to set the timing wrong..

Instead get an ignition lead from some parts store, remove the #1 coil, modify one end of the ignition lead so that it sits firmly into the coil, and naturally connect the other end of the lead to the spark plug. Then take the ignition gun signal from the ignition lead and you'll get an accurate reading.
(I've usually made my test leads out of SR20DE ones, which are good since they have the "hard pipe like part" at the plug end for easy fit on the plug, as the plug sits pretty deep in the head).

Another easy way to fail the timing setting is to take the ignition signal from the "test loop" that's in the coil pack harness. That loop is only good for measuring rpm in for example dyno use or such, but not for accurate timing measurement. Unless you have a special timing device that's meant for this kind of reading...but that's another story. Normal timing guns just don't work with this one, the timing will be way off.

Don't believe me? Set your timing to the 12deg that it goes with the way you set it now and lock the CAS. Then get the ignition lead and test with that one and see if there's any difference...

yeah mate i've already done this, i've tried the little loop at the back of the engine, i've tried a HT lead between the coil and the plug and i've tried the pickup on the coil wiring as it is in the video. They all give exactly the same result...
I know some people have trouble with the loop at the back, but it seems to work perfectly on my gun.

Things i'm going to try:
different timing gun
different cas
different balancer?
take the sump off and count the links in the chain to check the cam phasing.
Is there any possible way the consult timing figure could be wrong, like offset or something?

Yeah, I've always used the loop without issue.

PL

V unlikely the consult timing figure would be wrong.

PL

I found the problem, the exhaust cam was one tooth off. Not sure how this happened, I double and tripple checked the cam timing when i changed the cams recently, maybe it skipped a tooth when it first started and the chain was still slack.
anyway, thanks for the responses and advice.