TR2/3/3A TR3 Spark Plug Suggestions

[martx-5]

I need plugs for the TR3 engine rebuild. I milled the head 0.085", have 87mm pistons, and a mild cam. What should I be using? What brand and heat range??

 

[TR3driver]

I switched to Bosch WR7BP after Ken G. claimed actually finding more power on the dyno with them. Can't corroborate the more power claim, but they seemed to work well with both the shaved and stock heads.

There's a different number for them now, but your FLAPS should be able to cross-reference them. Apparently the 4-digit number (might be 4232 but I'm not certain) refers to a set of 4 plugs, while the WR7BP refers to an individual plug.

 

[martx-5]

Thanks Randall.

My local NAPA guy carries Bosch.

 

[sp53]

Hey Matrx-5, I only use champion plugs in my tr3. I forgot the number but if you go to shucks or Nappa and ask for the plugs to fit a 67 tr4 they sometimes respond better because most of the counter people freak out when asked for a tr3. Anyways I have tried AC, Bosh, and Autolight and I have found a remarkable difference when I use Champion. I mean big time. Please try them; you will not be disappointed. And you where right, I move the ABS Sensors on my Saab to mm and that fixed it. Thank you for kindly showing me the light.

 

[Andrew Mace]

The "classic" Champion plug was L87Y, now usually L87YC (copper core) or RL87YC (copper core; resistor plug). They also go under the stock number of 327 for the RL87YC.

I'm thinking that, with your modifications, you might want to go to a slightly colder plug? That would be RL82YC.

 

[PeterK]

I used to run NGKs and had constant rich fouling in the 3A. Champions were better. But now have switched to Bosch Platinum and better still (the problem is gone!)

 

[sp53]

I did a little experiment with spark plugs after I replaced my intake manifold gasket last month. What happened was, I had been buying plugs like AC and Bosh when they went on sale and had the AC setting there and thought I will just pop those in. Well they carbon-ed up quickly and the performance was poor so I went Bosh and had the same problem. I figured it was not the plugs and that I had screwed something up, so after much stress and self inflected shame and pain, I thought, I would try maybe the old champions I took out and my car came back like magic. Maybe I have set the fuel mixture or timing more toward champion (if that is possible) but the difference was clear.

 

[PeterK]

The Champion LY87C worked much better than the NGKs.

I'm running Bosch Platinum Plus #4032.

 

[martx-5]

It's pretty wild that there is such a difference in everyone's experiences with different brand plugs. It's enough to make your head spin. I'll see what the local NAPA guy has, and pick up something that has worked for you guys be it Bosch or the Champs.

... And you where right, I move the ABS Sensors on my Saab to mm and that fixed it. Thank you for kindly showing me the light.

I'm glad that it worked out so easily for you on that ABS system. The symptoms you gave were classic of the sensors not being adjusted properly.