[Ajs16400]

What spark plugs should I change to when doing the LT4 conversion on my SS?

[KingLT1]

NGK 6510

[Ajs16400]

Originally Posted by KingLT1

NGK 6510

Do you happen to know what the suggested gap would be? What is the difference between these and the stock zl1 plugs?

[ShockingZ]

Originally Posted by Ajs16400

Do you happen to know what the suggested gap would be? What is the difference between these and the stock zl1 plugs?

That's like asking about oil viscosity/brand. Its going to start a 20 page thread. I can tell you that everyone is going to tell you between .022 and .048. And they would all be correct for their builds - well most probably are. For you I'd just land in the middle-ish to make sure you got a nice strong spark, but also no too big of a gap. Nobody likes a big gap...lol.

Anyway, I'd arbitrarily recommend .032 gap as its usually one of the feelers in the set from autozone and its nicely in the middle of the range that most of the idiots on here will tell you - me included.

[ShockingZ]

Also get the 8 pack from Amazon for the best price, or if you need them locally both O'rileys and Autozone stock them. And I have gotten autozone to price match Amazon actually as well, so I was able to get them same day and for online pricing.

[KingLT1]

Originally Posted by Ajs16400

Do you happen to know what the suggested gap would be? What is the difference between these and the stock zl1 plugs?

zl1 is lower compression and uses a 6 heat range. I suggest a 7 heat range gapped around .032 for boost on a sbe lt1.

[Ajs16400]

Thank you for the responses.