Help with Triggle Angle setting please

hobieboy · Post by **hobieboy** » Fri Aug 18, 2006 12:30 pm

Hi,
I just strobe my actual timing against what MS thinks and found that there is 10 degree difference: when I fixed timing to 10 degree BTDC, my timing light lines up with TDC.

My current setting is: triggle angle=50 degree, Trigger A=1, return 6. Trigger B=13, return 19. Trigger C =25, return 31.

Does it mean that if I simply change the trigger angle to 40 degree, it should line up?

The main question: I think I'll run a max of 36 degree BTDC. Would 40 degree trigger angle be ok? If not, if I change it to 60, does the following trigger look ok -

Trigger A = 35, return 4. Trigger B = 11, return 17. Trigger C = 23, return 29? I'm using time based cranking so I guess trigger return really doesn't matter either?

thanks.

hobieboy · Post by **hobieboy** » Sat Aug 19, 2006 5:09 am

umm... anyone tried running such a "small" trigger angle (40) compared to timing needed?

thanks.

Post by **jsmcortina** » Sat Aug 19, 2006 5:32 am

With timebased don't fill in the return teeth.
Yes, you would be better stepping back over the missing tooth and using no.35 as trigger A to give a larger trigger angle.

James

hobieboy · Post by **hobieboy** » Sat Aug 19, 2006 7:04 am

jsmcortina wrote:With timebased don't fill in the return teeth.
Yes, you would be better stepping back over the missing tooth and using no.35 as trigger A to give a larger trigger angle.

James

Thanks James.

By don't fill in means put 0 in all 3? And does my 35/4/11 triggers look ok then?

thanks.

Post by **jsmcortina** » Sat Aug 19, 2006 7:11 am

hobieboy wrote:By don't fill in means put 0 in all 3? And does my 35/4/11 triggers look ok then?

Yes, set the trigger returns to zero.
The triggers should be 35, 11, 23 from your previous post. Check with a strobe.

James

hobieboy · Post by **hobieboy** » Mon Aug 21, 2006 10:35 am

Hi James,
Very strange - I changed the settings to 35,11,23 and set trigger angle to 60.
Verified with timing light that all cylinders' (4,5,6) timing are same as what MS thinkgs.

But now she won't idle well - my RPM oscillates by 300. Changed back to 1,13,25 and trigger angle of 40 then she's happy again: RPM osciallates <100.

Any idea?

It also looks like I won't be needing more than 30 degree timing so am inclined to stick with 1,13,25 & trigger angle of 40 if MS can handle that.

Post by **jsmcortina** » Mon Aug 21, 2006 11:01 am

hobieboy wrote:It also looks like I won't be needing more than 30 degree timing

Really? No "vacuum advance"? My table goes up to 51deg.

James

hobieboy · Post by **hobieboy** » Mon Aug 21, 2006 11:30 am

Mine is a turbo so at high load/high rpm situation, everyone I talked to suggested around 15-18 degree timing.

And I think the factory ignition curve has timing max-ed at ~32 degree.

If I can make MS to work with 60 degree trigger angle, I'd like to but not sure why setting trigger A to 35 (B=11/C=23) will cause idle to be very unstable.