Best plugs for '91 GT 150

[crbenny]

How does a GT 150 differ from a regular Johnson 150? What's the best plugs for this engine?

 

[ob]

Re: Best plugs for '91 GT 150

Mostly cowling design and a few stickers.I believe the GT model is a 90 degree engine.Someone will correct me if I'm wrong.Use the recommended plug.Champion QL77JC4 gapped at .030" if it is.If the GT is a 91' 60 degree design it calls for Champion QL78YC gapped at .030".<br /><br />Edit: I"m pretty sure you're engine is a 90 degree in which case it would take the QL77JC4 plug.

 

[Dhadley]

Re: Best plugs for '91 GT 150

The GT should be a Johnson 150 crossflow. There are cosmetic differences like OB mentioned but the heads are different too. Some XP/GT's had 200 port timing. QL77JC4's are fine. They still use 87 octane too.

 

[ob]

Re: Best plugs for '91 GT 150

Thanks for the clarity Dhadley.

 

[crbenny]

Re: Best plugs for '91 GT 150

Thank you guys