This may sound stupid... but I want to do this the right way, so I'll risk it:

Based on the pad stamp, my vette has a small block chevy engine from a 1969 chevelle or camaro. I've rebuilt the entire top of the engine with Edelbrock manifold, Doug's headers, Atomic 2 EFI and matching distributor. I was going to put in new plugs and run plug wires today, but the AC Delco R43S that was supposed to fit had too short a nose to seat into the block. I went back to my local places to get just R43 plugs... which apparently O'Reilly, Advanced Auto Parts, etc no longer stock or can order??? and got R45XLS plugs instead. Now these plugs fit, but will it run too hot in a 350/300 block? I read on camaro forums (due to the engine) that this will keep a street use car from fouling, but most of that was in reference to early cars and many with big blocks.

I've been very frustrated by how slowly progress has been on my 1970 resto, mainly because doubt kills progress and as an amateur I have a lot of doubt, including on something as basic as the right frickin' plug. Please, expert panel, tell me what the best plug would be to run on this SLLLLLLLLLOOOOOOOOWWWW going restoration.

As always, many thanks in advance.

 

You can get the R43 plugs on Amazon in many places and have it in 2 days. They are listed on Rock A——- too. The R45’s will be just fine.

 

In fact, I’d run with the R45 before using the R43s

 

I would consider NGK basic plug equivalent

all that ac delco is chinesium

edit..in for sale section someone was selling nos ac delco 44

edit 2
here
https://www.corvetteforum.com/forums...old-stock.html

 

"Chinesium" ... That's pretty funny. Thanks for the feedback. Since I have them already, since they fit, and based on that Cat Z06LMB's comment, I'll run the 45's -- unless there is a sudden outpouring of "don't do it's". Thanks guys.

 

Stick with the 44s or 45s. The 43s are too cold of a plug. Jerry