4 plug head to 8 plug head

[sgt snafu]

How much of a bitch is it to swap the 4 plug head motor(1985 2.3) to the later 1990 8 plug head motor? I have an intake with a carb off the old motor will it fit the 1990 motor? I know the new one is fuel injected. I want to go back to the carb. Do I need to swap out the ignition boxes or are they the same??? The new motor has a 5 speed trans and the old one was a 4 speed. Are they the same length? Any advice is appreciated.

 

[TireIron]

is this going back in place of the older motor? why are you replacing the older motor?

If this is because of a bottom end problem I would suggest keeping the 4-plug head and bolting it onto the lower end of the 90 motor. The 90 motor will have a plug where the distributor would be that you can remove and swap the distributor into the 90 lower end. The intake manifold from the 85 however will not bolt onto the 90 head, but the 85 head will bolt onto the 90 block. So what exactly are you trying to replace and fix?

 

[sgt snafu]

My Rat Rod has got a '85 Ranger drivetrain in it . It recently started smoking badly and using oil. I pulled the head today and found that a couple of the valves are burnt and there alot of play in the cylinders. I would rather not have a 8 plug head motor because the car is hoodless and I dont like the way all those wires appear on the motor. It doesnt have a clean look about it. Also I just put new exhaust on the '85 motor. Im figuring a rebuild is not in the budget and Im looking for a replacement. My older 4spd has also lost reverse. There a guy in another forum whos got a '90 ranger motor and a 5 speed trans for sale cheap and I was thinking that that might be the way to go. Just wondering about the intake and exhaust manifolds, if they are the same and I could ruse my old stuff. What about the ignition box? Will it have to be changed to convert to a 8 plug motor? If I swap the heads id have to get the old one rebuilt and its around 300 bucks. I wish I could find a 4 plug head motor and trans for a good price. I ve been to most of the local junkyards and the rangers seem to mostly have 6 cylinders.

 

[Mutant Pony]

Yeah, get the '90 motor and trans then find a good used head or find someone that will rebuild your head cheaper. $300 is quite high.

 

[Kenneth S]

An EZ fix for an 8 plug head, get four old spark plugs knock all the porcelain and electrode out of the center of it leaving just the steel hex/tread part, find you a piece of steel round stock that will fit into the "modified" plugs, cut the round stock to length, then have the round stock welded into the "modified" plugs on both ends (I heli-arced the ones I did), then just screw them in and tighten just you would a spark plug and then just forget about them. I've done this a few times and it works great.

Go get that 90 2.3 engine, and 5 speed, use your existing distributor. If the engine has the conventional "square" 4 hole lower efi intake you can get a adapter from Esslinger Engineering either 1" or 2" thick (it comes with four "freez" plugs to plug the injector holes on the manifold, and all the gaskets, nuts, studs, washers, and bolts) in which you can use a Holley 350/500 cfm or motorcraft two barrel carb.