Hello everyone. I am new here but I have a question for you. My ignition system in my 1996 Corvette LT4 desperately needs to be replaced. It is stumbling pretty bad. I am going to replace the water pump, opti, wires and plugs all at the same time. My question is what plugs to get?

I know that the stock plugs are ACDelco Platinum 41-943 and have a bad reputation of the puck falling off so I would rather stay away from those. I know a lot of people with LT1s really like the NGK TR55s and they have a good reputation but they are only a copper plug and rockauto.com says the LT4 needs a NGK TR5 anyway. Im assuming because it has higher compression? The LT1 had 10.5:1 vs the LT4 having 10.8:1 And this is still only a copper plug. I have heard it is best to replace a plug with the same material it had originally.

Looks like AC-Delco part#14 is a platinum Rapidfire plug that is equivalent to the stock 41-943. Do these have the same problem with the puck falling off?

As far as NGK goes, the platinum version they have available is a 3186 {#TR5GP} G-Power
This is what they recommend for the 5 engine code or LT4
I noticed that Delco does not suggest different model plugs for an LT1 vs an LT4

Does this make a big difference? I need to make a decision pretty soon so please reply with any advice. I have read through a hundred old threads on other message boards and forums but most of the info is several years old and only has to do with LT1s and not the higher compression LT4s.

BTW i have most available blot-ons including CAI, long tube headers, no cats, x pipe, catback, 52mm TB and TB bypass and plan on doing an electric waterpump and taylor full metal jacket wires.

Thanks in advance!

 

As far as the sparkplugs go, I just went thru this myself. I bought plat. plugs and then I read that a Copper plug delivers more spark. So I decided to try it out. I bought a NGK race plug copper set, v kind grooved, but not plat i pd 3.00 a pc and There is a difference, my lt1 ran alot better. granted, the downside is the copper one will omly last around 10,000 mile, so I read, but Im happier with the copper racing plug

 

ngk tr55ix are good in a lt1. upgrade to msd ho coil.