Noob engine question..Aftermarket head types g54b (RWD vs FWD)

[jimhappy]

Hey gang. I'm new to the mitsubishi world. Just bought an 88 Dodge Raider. It needs a new head.

Looks like a valve guide had come loose and danced around for a while, wollering out the hole. It has the jet valves and hydraulic lifters.

I'm looking at the new complete heads on ebay (https://ebay.us/9uvyKz) and amazon that can be had for $400ish (no jet/mechanical lash adj)

There's a warning that concerns me though: "this cylinder head only fits RWD, and it does not fit in FWD." What is the difference? Can I use this on my 4X4 raider?

Any help is greatly appreciated.

[geezer101]

Hi and welcome to mightyram. The difference between FWD and RWD heads is the provision for the water pump to be driven off the rear of the cam. As your Raider is a RWD configured engine, you're good to go. The listing should be for a Mitsubishi based engine though as the Mitsubishi intake on US trucks is on the drivers side while the Mazda is not only opposite, but 12V as well.

[pennyman1]

the Mazda is 12V on the 89 and up 2600I motor, not the 87-88 B2600 motor - that is pure Mitsubishi, at least in the US.

[geezer101]

the Mazda is 12V on the 89 and up 2600I motor, not the 87-88 B2600 motor - that is pure Mitsubishi, at least in the US.

Hmm, only ever saw 12V in Mazda trucks. But it's worth noting just in case someone ends up trying to buy one and gets stuck with a head they have to pay to freight back.

[jimhappy]

Exactly the info I was looking for. Thanks.

[StarquestMan]

Just spotted this thread and thought i might add that I am currently running a head off an 84' dodge 600 (FWD mechanical lifter w/jet valve narrow block car) on my 87' Ram 50 4x4 5 speed wideblock. I had a friend with a lathe cut the part of the camshaft that drives the FWD style water pump pulley off so i could install the oil plug. that seems to be the main thing that needs to be done to run a FWD head on a RWD application. the head casting is identical between the two as far as i can tell, only the camshaft is longer and a seal instead of a plug is installed. even the rocker cap assembly at the rear of the head is the same between the two.

[pennyman1]

some years the air pump was cam driven on caravans as well. The other way to fix it is to swap a truck cam for the fwd cam. Most fwd heads are non jet valve, but they are inferior to the newer non jet heads made now.