04SeaFive

I purchased a set of Holley Valve Covers for my 2004 Base C5. The advertisement said good for all LS engines, but when I received the covers I learned that the coil mounts are for LS3 and up Coils; that the LS1 coil mounting holes are too close and will not bolt on both ends.

I called a local speed shop who told me that I should buy LS3 coils and harnesses. I believe those are for C6 Corvettes, so will that be a problem if I used those?

Also, while looking for LS3 Coils I've found two types, round and square. I think this refers to the cable plug-ins, but not sure. Which style should I buy? Will one or the other work with my current coil harness or do I need to purchase a new harness?

Finally, if LS3, LS4, LS7 coils are fine, can anyone give me the GM Part numbers for the recommended coils and the harnesses?

f6john

This came up a while back and one poster said he went ahead and used his LS1 coils and mounted them with just one bolt and everything was fine that way for him.

04SeaFive

Yes, I saw that and considered it, but worry some about losing ground or causing an arc, so if I can use C6 LS3 coils, I think that's my preference. Thanks for the reply.

XLR8 C4

On my 03Z with Holley covers I use these coils and harness. Plugs in your existing coil harness to use the LS2 coil.


Coil P/N is 12573190

Harness can be found here

https://www.eficonnection.com/home/p...-harness-d514a

CTD

LS2 coils will work as well, I picked up all coils including the harness.........plug & play.

Tusc

Remote mount the coils. Racetronix probably sells the loom extension needed. I stashed the driver side coils inside the fenders on the vertical frame wall and the passenger coils in the fender on the horizontal frame rail. Works a charm. If you consider this, pm me and I'll get you my wire lengths.

04SeaFive

thank you, looks really nice!