Critical parts that are no longer available

[XfireZ51]

Originally Posted by Blue Flame Restorations

Member Y-ME (Dan Vlach) is parting out two (2) ZR-1's right now. Having more than one ZR-1 in the stable, I purchase the parts no longer available to put on the shelf. It's a "must".

The list is short. I always make sure I have extra ECM's and DIS modules on the shelf. I even keep ZR-1 specific body panels and AC lines but I'm pretty anal. Nothing else is really a show stopper for me unless I'm missing something?

Most everything else is C4 specific.

Brett,

Even the ECMs aren't that critical. For the most part they can still be repaired relatively inexpensively. I would say that the critical path is the DIS module for now.

[Blue Flame Restorations]

Originally Posted by XfireZ51

Brett,

Even the ECMs aren't that critical. For the most part they can still be repaired relatively inexpensively. I would say that the critical path is the DIS module for now.

I keep hearing from time to time that people have a hard time finding them or knowing where to get them repaired. Maybe they just don't know where they can get them repaired????

Thanks, Dom.

[Bob Eyres]

My DIS module went bad very early, about 17 years ago. Replaced under warranty. I try to keep all replaced parts. I'm going to check to see if I still have it.
Anyone ever had one apart?

[Don in VT]

This is for "crabs",

Thanks for the great solution for the ABS relay. I will save the fix. I actually used a similar solution for a Porsche 928 electrical issue.

Thanks again

Don

For the rest of us:

It seems to me that the DIS module is the electronic equivalent of the 800 lb gorilla sitting in the corner of the garage. We just ignore the potential problem and hope it goes away. I guess it has not been a big issue up till now as that the component has been very reliable. As noted by others the cars are getting older and we will probably see more and more of them fail. As the DIS units fail and if the owners can't find a replacement the ZR becomes useless, period, end of story unless you do an engine swap (back to L98, LT1/4 or LSx.

We use the ZR for lots of long trips and that will come to an end because we can't afford to have a car stuck 1000 miles from home with no way to fix it and drive it back home.

This might be a good time to flip this issue of the DIS over to the Technical Discussion side so folks like Dynomite, Mark H and many others can weigh in if they are so inclined.

I will restart the DIS availability and alternatives (if any) on the Technical side posts.

Thanks all for all the help with trying to understand this issue.

Cheers,

Don in VT

[XfireZ51]

Originally Posted by Bob Eyres

My DIS module went bad very early, about 17 years ago. Replaced under warranty. I try to keep all replaced parts. I'm going to check to see if I still have it.
Anyone ever had one apart?

Bob,

Because of the environment the DIS lives in, they epoxied the unit. That means it covers all the internal components. Digging all of that out would be a nearly impossible task and even then you probably can't do it without damaging the components. Marc H has an IM unit w/o the epoxy and there's a pic on his website of it. Had the LT-5 been designed w a 24 tooth reluctor, it would have made life much simpler. Maybe Mercury Marine has a solution.

Brett,

Marc H has a stack of ECMs and has a reliable place for hem to be repaired. May want to check w him.

[Don in VT]

Mark H. has taken a unit apart and actually has a pic of the unit on the inside. It has 2 large IC's and other components. Repairing the unit looks to be difficult.

Thanks

Don

[XfireZ51]

Originally Posted by Don in VT

Mark H. has taken a unit apart and actually has a pic of the unit on the inside. It has 2 large IC's and other components. Repairing the unit looks to be difficult.

Thanks

Don

It was never taken apart. He got it as is. essentially the IM is a co-ECM. Since the basic code for the LT-5 is a derivative of the L98, GM came up with other ways of accommodating the unique aspects of the motor. That's why we have things like secondary injector relays. According to speakers at the Gathering, the need for unique ECM code was a primary consideration in the scuttling the second generation LT-5.

[LGAFF]

I know Motorola did some of the prototypes, but who ended up making these?

[Vetman]

I will show my ignorance here. What is a dis an IM and where are they located and what do they do? Is it within the ECM. I do know what and where that is.

[GOLDCYLON]

Originally Posted by Vetman

I will show my ignorance here. What is a dis an IM and where are they located and what do they do? Is it within the ECM. I do know what and where that is.

The DIS (Distributerless Ignition System) Module resides under the plenum.

They are long NLA in the GM system, They are not being rebuilt at this time. You have to get one at this time from a total car part out.