What fits the head bolts?

[red450ih]

I need to remove the heads on my 91 Exp. Where and what size tool do I need? I am also doing some other engine work. Is there any improvements I can make over stock and still maintain good fuel milage?
Thanks

 

[Chav]

When I replaced the head gaskets on my 93 OHV 4.0 I had to use torx 55 to take off the head bolts. Hope this helps.

 

[DCider]

I have done a few mods on my '91. The biggest (may be a cumulative thing) mod for an increase in gas mileage was the installation of the JBA headers. This was the last thing on the exhaust to be added and the biggest pain on my high mileage Explorer. YMMV.

So far on average I have seen about a 2-3 mpg increase on both highway and around town when I'm NOT "on it". When I'm "on it" the mileage is about the same. I'm not constantly "on it" so the mileage would probably drop below what I was getting before if I was terminally "pedal to the metal".

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David Cider
'92 Explorer XLT 4x4 4.0L 4Dr 4...

Current Mods:
JBA silver ceramic headers, hi flo cat, Thrush muffler, KKM Air intake, SuperChip, Magnacor wires and Motorcraft Double Platnum plugs

Pending Mods:
4" to 6" Suspension Lift, Tires & Wheels, Euro Guard bumper and Warn winch, rear tire rack w/gas can provisions, screw supercharger and high flow heads...