I have gotten myself so confused on which spark plugs to go with. Anyhow I have a 306 cam, LE1 heads, a hair over 11:1 compression, and plan on spraying 150-200 shot of nitrous. So that is about 400rwhp + 150-200 shot. Which plugs and what gap? Thanks for any help.

 

NGK TR-6 gap at about .030 to .032 ish

 

for your power level I would run the TR6 listed above as the NA plug...for nitrous I would run the NGK BR7EF with the same gap.

 

^^^^^^^^^^ I'm with Ray here


A extended tip or projected tip plug is not the best for nitrous applications. You can spray 150hp with them fairly easily. But after a certain point it is time to pull them out and run a standard plug.

 

If your going to run a decent size shot the BR7EF is the plug of choice as mentioned here. I just recently picked some up to replace the TR-6s that I was running. I'm about a 140rwhp shot now but plan on upping it to a 175shot in a few weeks. Now that the good air is here and it's time to try for a new PB.

 

BR7EF is stocked as part number 3346 if you need it. I just picked up some last weekend. I gapped mine to .032 for the 200 shot.

 

I know this is a little old but Ive got a stock lt1 with lt4 hot cam and about to buy some nitrous. I was gonna run around 125 to 150 shot. Are the TR6 plugs ok or would I need the BR7EF plugs. Im not planning on running any bigger shot than those.

Thanks

 

The same plugs choices I suggested above apply for your application.

For a modified internal NA engine ----TR6

ANY nitrous at all BR7EF...even a stock engine
Heavy modified engine plus nitrous might even need either the B8EFS or B9EFS for stock heads.

 

I agree Ray, the only thing I found with running them N/A is they load up if you drive it slow for a long period of time. But they clear out with a short blast of the peddle... and your good to go.