I'm just wondering if the NGK TR55GP are a good spark plug to buy for an LT1?
Also what is the difference between the TR55 and the TR55GP?

 

The gp is a platinum plug. I've always ran normal tr55s with no problem

 

TR55 is best plug for lt1, use the one that cost a dollar ninety nine hehe

 

when I got my bird and did plug and wires, I had first put bosch platinums in, didn't know any better at the time. About a year later I put TR55's in and noticed the car ran smoother.

 

I would only run platinum plugs if i had a mercedes

 

The platinum version of the TR55s are exactly the same as the regular TR55s - they just last longer.

 

thanks everyone for the input
so the platinum plugs last longer than the copper ones?
I thought it was the other way around lol

 

No, platinum plugs have more resistance to build-up, so they last longer.

 

Ok so now I'm wondering if I should take back the tr55gp's and get the tr55's?
If theres no real difference in performance I should just take them back and save myself a few bucks.
What do most of you prefer/use?tr55?tr55gp?

 

I've always used the regular copper electrode TR55s.

 

The platinums will be fine as long as you're not spraying..

 

Platinum plugs are no good for high performance use.
When I removed my stock AC (platinum plugs) from the stock engine at about 25k miles, PRIOR to installing TR6's to run nitrous, 5 of the 8 plugs had the little platinum puck missing from the ground electrode. Platinum is a VERY hard material to have ricocheting around in your engine!
I'll never again run them in anything I own that gets hard use.