MSD TL setting suggestions please

[Matt_E]

Alright...trying to get some ideas here for setting up the MSD Pro Digital II ignition box.

I'll have to check what I currently run - it was a setup recommended to me by John @ Jetskisolutions.
All I know for sure right now is my static timing - that's set at 30 Deg BTDC.

The rest of my setup:

61x @ 83mm bore, FS porting (std port heights, exhaust widened, bottom modified for more flow, intakes roughed, exhaust polished
62T cases, ported
35 cc domes, about 190psi compression
MSD TL, about 30 deg initial advance
B-Mod
VForce 2 reeds, reedspacer
Dual Mikuni SBN 44s on Riva Manifold
Concord 13/16 cutback 3mm

Suggestions?

 

[SuperJETT]

There is a really good post on pwctoday that I used to have in the Tech FAQ there, but since that disappeared, I'll search for it.

 

[Matt_E]

Thanks Darin!

 

[SuperJETT]

http://www.pwctoday.com/showthread.php?t=22548

That's not the one I was thinking about though.

 

[Matt_E]

I just found that one as well. So you're thinking there's another one.

Did you post in it?

 

[Matt_E]

I found John's suggestions:

Set you static timing at 35 degrees

Set retard begin @ 4500

Set max speed rev limit at 8500

Set max speed retard @ 20 degrees

Set max timing to Max

Set min max rev limit Off

Set Max retard On (+15 degrees)

Set electric start on

Set retard begin rpm Off

You should be able to use this with 92....but check for deto. I run 2 gallons of AV gas to each 5 gallon jug, and have never had a deto problem....even before running the AV gas. To be conservative, you may want to try 30 static, and take away 15 degrees, or more.

35 degrees seems pretty far... Ideas?

 

[SuperJETT]

John doesn't freestyle, so I don't pay much attention to his recommendations on stuff. (especially after he blamed the tuning issues on everyone using a "wet" pipe)

The post I'm trying to find had Darren Hedlund's timing guidelines for a Yamaha, including final timing. I think he said to always end up around 15 or so.

 

[Matt_E]

I have read that number (15 final) a few times as well.

It's interesting that I actually ran those recommendations last season without a hitch - I may have gotten lucky, as 35 degrees initial advance, coupled with pumpgas on 190lbs compression seems somewhat risky, put mildly.

My TL brain's timing LED is burnt out which made timing the ignition a bit tricky. After doing it again yesterday, I finally found a reliable way to time it with just spark as indication. I have it set to 30 degrees.

 

[Matt_E]

Alright, here's what I ran last season:

appr. 33 degrees initial advance
4500 start retard
19 degrees taken off at final
8750 RPM limit

I changed this yesterday to:
30 degree initial advance
4500 Start retard
15 degrees taken off at final
7500 RPM limit


I spent all a good three hours last night completely rewiring my Total Loss. Previously, I had the two coils and relay on a metal plate that mounts in place of the stock electrical box.
The brain sat on a plate strapped to the tank. Kind of neat, but it was a hellacious mess of wires.
I now have everything on the metal plate. That eliminated quite a bit of extra wiring and should go a loooong way towards cleaning up that bilge.

 

[Idok]

much better on the final revs too matt.....I dont think we need to be running 9k rpms :biggrin:

 

[Matt_E]

Actually, I changed it around yesterday...

32 degree initial advance
4000 Start retard
15 degrees final
8250 RPM limit