spark plug q

[Torinalth]

hey guys. i was thinking of going down to a one step lower heat range (trying to fix my detonation) and wanted to see what was what. i used the autolite 764s... and noticed advance stocks 765s... is that one higher or colder or what? is there a certain plug i should go with? i prefer autolite and NGK for brands... just kinda curious.

Torinalth

 

[Kilgore Trout]

I believe with Autolites the 764 is the stock replacement and 763 is one step colder. I have noticed people posting about also using one step colder plugs in the rearmost cylinders next to the firewall as well. The rear cylinders are hotter due to reduced coolant flow.

 

[03ghoststang]

well you could go one range down, but what octane are you using????

 

[Gearbanger 101]

Time to start running Premium fuel, ya cheap skate.

 

[Torinalth]

damn man... its 290 for 87.... i dont want to run premium without at least a tuner to give me some timing or something. on a side note i dropped a can of sea foam in the tank and jumped to 89 octane today and redlined 1-3 and didnt get any detonation.... it was a cooler night... however it was doing this is cooler weather... stupid finicky motor. wish ford racing was still selling their 99 cobra package (motor, tranny, and exhaust) i'd be ready to swap out to get 4v and a new engine. 123k so far and think my engine could use an early retirement.

thanks for the heads up. one auto store did not have 763s.... so i'll drop in some more 764s tomorrow and run 2 cans of seafoam through the intake to see if i cant clean it up a bit. this detonation sucks.

Torinalthq