LT4383

I purchased a complete MSD opti last week.Ive did THREE opti installs on my Corvettes so Im not new to this.I double checked the plug wires to make sure they were installed properly and they are.The car will not start now and Im completely stuck now on what to do.

kylebuck89

Well did you check to make sure the little pin on the cam shaft went into the right hole on the opti?

93Quasar

I've never done an opti on a late C4 to know how it lines up. I just put the MSD on my 93 and it fired right up. But I have a splined shaft that can really only go on one way. Are you saying there is more than one way an opti can go on the later versions? If your plug wires are right, coil wire is on, and harness connector is hooked up, there's not much more to it. Any codes? You can triple check your plug wires, but they'd all have to be wrong to not fire at all. I'd be calling MSD to see if there's a way to verify if you got a bad unit.

pianoguy

Does it fire at all? Could the timing adjustment screw be set wrong (I think they are supposed to be 2 turns out from the factory)?

Port A Vette

Yes on the later models you can put it together out of phase if you are not careful. The MSD instructions have you check the rotor position on the old unit before you remove it. Then they have you install the distributor without the cap to make sure you have the rotor lined up in the same position. Then they have you install the cap on the car. If you are careful and make sure the pin is seated into the correct slot you can install it with the cap on. You probably have your's installed wrong. Check this diagram http://shbox.com/ci/opti_mounting.jpg you need to get the pin into slot A. You probably have your pin elsewhere.

Larry

kylebuck89

make sure it goes into the hole thats differnt than the other ones..

also make sure that the motor is on Number #1 cylinder.
the little pin on the cam will be at the 9 o'clock position too

STL94LT1

This isn't neccessary. If you get the camshafts dowel pin inserted in the opti correctly, it doesn't matter about the rotation of the engine.

LT4383

I didnt checked where my rotor was when I pulled the stock opti.Could the rotor have been installed 180" from MSD?I have no way of telling which is the proper way to have it installed?Thanks for the help guys.

SportsCarsUnlimited

Hello
You did not say why you installed a distributor on your car? Did it stop running or your trying to update to the MSD. If it stopped running there are lots of reasons to lose spark, Not only the distributor. I have seen a 94 corvette that the chevy dealer installed a new distributor and charged the customor $1100.00 and it would still not run, he had it towed to are shop and the only thing wrong was the power wire to the coil had corroded so bad it fell apart, Dont allways think the worst case.
David

LT4383

I pulled it back off tonight and checked the rotor assembly.It only goes on ONE way.I reinstalled the opti to the pin on the cam FIVE differant times just to make sure it was right.It fell on totally flat against the timing chain cover on the last try so I knew it was right.I made absolutely sure the wires were on correctly which Im questioning now about that darn drivers side from the first time.Hooked everything up EXCEPT the waterpump.belt,and it fired right up as smooth as its EVER been.Thanks for the help.Now I have to see if my miss at 5500rpm is gone later this week after its back together.

pianoguy

Great news!

Port A Vette

Wait till you run it up against the rev limiter. The MSD will surprise you. I had a dying opti I nursed for 6 months before I finally swapped to the MSD and the change for me was quite dramatic. You should be all smiles this weekend. It helps you forget the pain of seperating the inertia ring from the hub on the dampner assembly.

Larry

Port A Vette

My car also improved with use. You will need to drive it more which is a good thing.

Larry

LT4383

I didnt have time to drive it yet because it was too late but it was running.I have a ATI superdampener so I didnt have to remove it to take off the opti or install it.Saved a TON of time and headaches.I will keep you up on the hopefully NEW top end power I have after a teast run.Thanks...............

Port A Vette

Using an ATI Superdampener is cheating. Why didn't I think of that? I had to beat mine off using the broom stick while turning the dampener.

Larry

STL94LT1

Yeah but try pulling the ATI with the engine in the car.

Redeasysport

This is the key to installing ALL year Opti's. It what I call "Pops" against the timing cover when the alignment is correct. Slides right in tight against it. 92,93,94,95,96 it doesn't matter if you have to tighten it down with the bolts to touch the cover it is on wrong. I hope all the Newbs read this.

RogerZ06

Thanks for the advice

Gonna be installing my own here soon.

LT4383

I had to tear it apart again so I could make absolutely sure what plug wires were on what cylinder.I had 2 that were crossed and that was the whole problem.I still have the miss up top but its better after I turned up my fuel pressure to about 48psi.Im still working on it.Thanks for the help guys.................

Port A Vette

Have you changed your plugs and wires? My wife's LT1 impala had a bad miss and when I changed her wires I found a spot where the insulation had been kinked and was burned through allowing the spark to jump to ground. I also changed her plugs. When i did my opti I changed my plug wires and plugs also. I used the stock LT4 wires and plugs. The car has plenty of power now - but before the ignition work it could barely get out of it's own shadow.

Larry