I was wondering what the passage is (about the size of a dime) that the washer on the end of the thermostat blocks when the stat is wide open. It only blocks it totally when the stat is wide open (200 degrees with the stock stat) otherwise it flows to varying degrees. It's a 1/4" away from blocking it when closed but as it opens up it gets closer until it blocks it when wideopen.

 

ttt

 

I do not know but I would think it's something to do with emissions.

BfB

 

A real stumper, huh. When the passage is blocked it forces more coolant flow to the back of the block.

I was thinking of running a thermostat without the extension but the engine would not be evenly cooled. I couldn't find it on the ford manual CD either.

 

Throw it away and install a 160 especially if you race. Cooler engines live longer.
noelvm

 

LTNBOLT
You can still use the short thermostat, but you should plug the hole underneath the stat. Its no different than removing the bypass hose from the water pump on a chevy or whatever. It will take longer for it to warm up, but in the case of the lightning I don't think it would cool any better if you disabled it. (the bypass)

Actually the bypass on the lightning is a slick deal, it shuts off the bypass when the motor gets to hot. Who woulda thunk.
Dale

 

Noel,

Actually that's what I am doing. I had a Hypertech 1011 (160) but I pulled it out to try the 170 degree. In the meantime I gave the Hypertech away and couldn't remember if it had the extended end on it or not. That was why I asked the question. BTW, the Hypertech does have the extended end.