Did you adjust the timing from the MSD factory setting?

If you did, how did you do it?

 

I was hoping you would get some replies. I have just replaced my Opti with an MSD and not sure if it needs adjusting. My engine is a stock LT1. Even if I were to adjust the timing I am not sure how I could, there is no timing tab mounted on the timing chain cover to aim a timing light gun at.

 

I'm looking at the MSD Opti and asked the same question. Once installed, how do you adjust it??

 

http://www.msdignition.com/pdf/8381_frm27275.pdf

 

The instructions tell you how to turn the adjust screw. I think we all want to know how to adjust for optimal performance.

 

Just in case yall didn't know.

 

ok....I asked for that.

What I meant was it seems that once the new opti is installed and tucked away, that screw would be nearly impossible to get to.

 

No, it's accessible.


About as much as anything else on a C4 is "accessable".


I installed mine untouched. Runs fine. But until I get some data from my PCM I'll never really know.

 

I used a long extention with a 7/16 socket, Real easy to get to. The instructions state that 2 turns out is equal to factory specs. After many trips up and down the road and half turn increments i found it ran best all the way turned in. The instructions are vauge and the MSD 800 support line was usless. I recall another forum about this that came to the conclusion the the engineers at MSD added this feature to allow for modifications and timing chain wear on various vehicles. Because the timing absolutely cannot be adjusted manually. The LT1 timing is strictly controlled by the computor. By the way my 93 is completely stock. My advice is......... At operating temp, start with it 3 turns out and adjust in half turn increments until satisfied . Might have to go back and fourth a few times, you should feel the difference.

 

I didn't have to adjust the timing on mine. It ran perfectly from the start and still runs great several months and a few thousand miles later.

 

I don't know what the 7/16" socket fits, my adjusting screw has a screwdriver slot in it and the screw head is nowhere near that big.

The 2 turns out on the MSD is equal to the mechanical built-in manual factory setting of the GM Opti-spark unit. It is equal to about 4*BTDC. The computer sets the run timing to about 20*BTDC at idle and advances timing to about 40*BTDC at WOT.

There is no way you could set the optimal timing by making adjustments a few increments at a time running up and down the road. The only thing you would do is set optimal for that time of day, ambient air temperature, humidity, barometric pressure, and engine temperature for that moment in time. I doubt you could tell by the seat-of-the-pants the difference other than the above mentioned parameters.

The 2 turns of the MSD unit is the equivalent of the GM built-in 4* BTDC mechanical factory setting and should be left alone until you can put the computer on a machine to see if you have about 20* at idle and 40* at WOT for a stock engine. The MSD certainly can be adjusted mechanically by changing the adjusting screw while the engine is turned off (preferrably) which can set the mechanical aspects of the distributor +- 5-7* by its design as the OEM unit is designed to be 4* BTDC (no adjustment) without the computer turned on.

You could change the preset timing (mechanical design) that the computer doesn't see but neverless changes the timing mechanically and the computer doesn't know any better. I believe later years that have sensors for the crank and cam location may not work the same.

Just about all engines, even new, can be tweaked to run a little better and certainly older ones with some wear, but then you have to find the optimum and that may put it right back to where it was previously set due to the slop of the wear.

With some mods to the engine, the adjustible MSD can usually help performance by increasing the mechanical timing BTDC when computer controlled.

I left mine set as-is out of the box and runs great. When cold, it screams, but on a hot day at operating tempreture it definitely runs a little calmer.

Take this for what it's worth, but that is how I understand the purpose of the adjustment. Your mileage may vary.

 

Makes sense. Gues the best results are to leave it set as it came from the box and let the computer do it's thing

 

I e-mailed MSD for info on the timing adjustment and this is the reply I received,



Sir,

The MSD distributor is set for factory operation from our facility. The
only real way to adjust the timing and check it would be to mock up some
kind of timing pointer and use some type of timing tape on the balancer.

Thanks.
MSD tech

 

Thanks for that info. Makes sense.

Now if they would come up with the mentioned items for us.

 

Not all of them come with the adjuster 2 turns out, out of the box. Mine was all the way in and made my headers glow. I backed it out 2 full turns and all is good.

 

I put the MSD on a track only car last year. I left it set as it was and put it on. Car runs great.

My only complaint is that you can't see it after the water pump is on and I think it's a very good looking piece.

 

Maybe my 93LT1 has a different set-up than most of you fella's. But the adlustment screw can be clearly seen from the passenger side in the vicinity of the front of the head behind the waterpump without even moving wire looms out of the way or anything. It is a year old now, maybe they made some revisions. the reason I used a socket on it was because the slot for the screwdiver method was too shallow and the screwdriver kept slipping about to strip the slot. As far as all the technical stuff, you have to excuse my ignorance but I know "seat of the pants HP" when I feel it. I'll try to post a pic.

 

No ignorance implied. Its just my seat of the pants are not as sensitive as some I guess. Must be age.

Yes, it can be viewed as you stated, but I don't remember it being so big. Have not tried to adjust with screwdriver...didn't realize the slot was so shallow.

 

I just had the MSD Pro-Billet installed in my 92 LT1 a couple of monts ago. It is running fine except the car just doesn't seem to have that pull me back in the seat feeling when I get on it. Does that require an adjustment on the opti that you all are talking about.