Hi all i just bought a 1989 F150 custom, 4.9 six cylinder, 5 speed manual, goes ok but not as well as i thought it should? a previous owner replace the air cleaner wiith 2 K&N washable filters which were half blocked and since ive cleaned them and fully service the truck it seems to go better.
Im wondering if anybody has tried removing the smog system and if they go any better?(here in nz its not illegal)
The other thought was put a centrifugal supercharger on it? i want to use it to tow my old Pre65 racecar.

 

Hello and welcome to the forum.

No, emission systems on these motors don't hurt any performance, and as long as working properly, actually help you out.

Check out http://oldfuelinjection.com/?p=3 to get a little more info how the EFI strategies run on these rigs.

You can build up a 300 as wild as you want, but the usual Mazda M5OD-R2 five speed tranny can last a long time even towing, but doesn't like bumped up horsepower. Now, late 80s half ton trucks with the 300 could also be ordered with the heavy duty ZF S5-42 trans more rarely, so you have to take a look at what you have. The Mazda's case has square external ribs, and the ZF's are diagonal.

Check out http://fordsix.com/forum/index.php?s...fb4f6ae191d7f2 to play with your 300.

Adrianspeeder

 

Hi thanks for that, ive come to believe that if it doesnt have a cat on it the smog pump is not doing anything? and it appears my truck does not have a cat.

 

The air pump still helps clean up the exhaust. Manufacturers put the air pumps on vehicles before the cats were mandated.
I think the 5 speed tranny typically was rated for about 2,000 lb towing capacity.

 

I've drug a lot more with the M5OD no problems, but just take it easy on bumping the power.

Also, if you do have the M5OD and not the ZF, be sure to check the level at the fill plug. They like to leak only while running down the road from three dried out rubber caps at the base of the shift tower.

Adrianspeeder

 

Thanks Adrian, yes it is the M50D, oil level is fine ive just fully serviced the old girl.

 

wheres the best place to get parts for these old girls
Mines missing the fan scroud and id like to put an orginal air cleaner back on it and a new thermostat housing?
cheers Barry.

 

rockauto and LMC truck.

Adrianspeeder

 

Shipping to NZ is going to be a killer.........