Novice C4 Spark Plug Question
 

Good day everyone,

Getting the corvette to ultimate daily driver status. I have no idea how old the sparkplugs are. It doesn't hurt to change them out. I have a full set of AC Delco Rapid Fire single platinum Sparkplugs. Been reading the shop manual, haynes, youtube, and forums. A few questions for y'all.

Do the sparkplugs come gaped?

What tool do I need to use to gap them?

I have Rapire Fire #5 in my 89 they are pre-gapped at .045
I use just a .99 cent gap gauge you can pick up at any auto parts store or Walmart to check the gap on each one
https://cimg1.ibsrv.net/gimg/www.cor...82a5d97db.jpeg

Btw what year is your car and what plugs did you get?

Thank you for the info! It's an 84. It has the #4 on the box. Do i need to get #5?

I would verify each plug is properly gapped to be sure.

It would also be a good time to install a new wire set too.

Quote:

---

Originally Posted by Early-Fuel-Injection (Post 1599186529)

Thank you for the info! It's an 84. It has the #4 on the box. Do i need to get #5?

---

Actually the #2’s are the ones you want for the Crossfire engine gapped at .045 I don’t wven think the #4’s will fit also don’t forget to put some ant-seize on the threads

https://www.oreillyauto.com/detail/b...rk+plugs&pos=3

These are the ones I have. I was looking at the other ones in stock. Which one do I need to get? Appreciate your help.

https://cimg3.ibsrv.net/gimg/www.cor...ddddc590ee.png
https://cimg4.ibsrv.net/gimg/www.cor...c1e6cc3519.png
https://cimg5.ibsrv.net/gimg/www.cor...19d5cf40d7.png

I buy such items at my local AC Delco store; in your case I would get the Auto Lite plugs.

I would suggest you get the exact plug called for in the FSM and gap them as required. You will notice improved drivability and MPG will improve if your old ones have issues. BTW- platinum spark plugs last longer but copper plugs have less resistance and don't last as long.

Thank you! I got back to the store today and exchanged them. That will be my project for the week.

As someone mentioned, replace the wires too.

I always check the gap on my plugs, Takes all of two seconds to toss them on the gapper and run them up and make sure they stop where they should.