Anyone had this problem...

MSD BTM set to 1.5 and noticing a slight sputter at 3/4-full throttle before or during the onset of boost ?

*Using advanced timing on the dist.

 

you dont need retard before turbo kicks in.
need more info to diagnose properly, but you probably are taking too much out, if you run under 10PSI in decent weather and alt you may not need any retard as your distibutor takes care of quite a bit. the sputter sounds like fuel not burning cleanly untill higher cylinder pressure at higher rpms take over to help combustion


[Modified by rtype11, 8:15 AM 12/11/2001]

 

I have accidently turned my btm up past 2.5 and to almost 3 before.. I got the same thing.. Is it harmful to the engine?

 

kinda harmfull, you be the judge - what is happening is missfire or no fire at all in one or more cylinders, cars with CFS get timing signals from ECU that are different from that of MSD. you do get some extreme cylinder pressures and the rods being pushed right down into the crank at TDC instead of 12 degrees ATDC.
you dont need retard with less than around 10psi and good air temp/density - BTM is really for peeps in Denver

 

thanks man.. yeah i am scrapping it hopefully this weekend when i get my hondata in..

 

I agree. The BTM is only needed at high boost or thin air. I run mine at .5 at 8 psi with timing advanced. That way i get timing advance with no boost and retard when boost peaks. I just wish it would be more adjustable in tenths of a degree.

Randy

 

So is it bad to have my timing retarded 3 degrees at 7psi?

 

ttt

 

I was under the impression that the 6btm could go up to 3 degrees per pound of boost, whcih meant you could turn the **** anywhere in between to achieve desired retart...

you dont want 14psi w/ .5 per pound.. and end up with too much retard.. which i think is very bad just like toomuch advanced timing

ttt...

i'd like to know this as well... can it be .25 / lb of boost? or does it have to be .5

 

What is btm? I think I know, but am not sure.