Questions about '86 F250

[TheKing86]

I don't see that anyone addressed the louver in the chin of your engine spacer plate, but yes, that is meant to be there.

I'd assume to be an indicator or rear main seal leaks, or just to let the oil out so it doesn't get onto the clutch?

Bill says to mill the heads, but reality is that stock pistons are too far down the bores to have any effective quench.

A better approach would be to zero deck the block, as a normal head gasket is .040-.044" (compressed) anyhow.

Increasing CR without quench only exacerbates the octane problem in my experience.

I would also go with a towing cam, rather than an RV cam.

This engine is the second time I've made that mistake.

Also be sure to install the cam 'straight up' (tooth directly above crank keyway)

The '88 and up EFI engines used a straight up double roller timing set, but the Cloyes #3079 is only $42 on Amazon or Summit.

Taking out the 4° cam retard really wakes these engines up.

If you're doing away with EGR (and even if you aren't) recurving the stock DuraSpark distributor will help with power.

An Edelbrock Performer intake (with or without EGR) helps add a bit of flow while not having big runners that destroy bottom end.

It will also shave 50 lbs or more off the engine weight.

Plugging the heads in the rear takes a pair of .666" welsh plugs, just like the front.

Or you could simply tap the holes for shortened bolts.

I have my exhaust manifolds plugged (capped)

My advice is to be sure you have oxy-acetylene torch to get the injection spider manifolds off.

The caps can be bought in a pack of 10 at NAPA.

When I first saw the louver I was a little confused as to what was going on:nabble_anim_confused: but now it makes sense. Probably just to be an indicator or help with heat.

Is there a big difference in lift and duration between the RV and towing cam? I'll definitely be doing a double roller and recurving the distributor as I've seen recommended and done many times. I've heard Scott/TheMadPorter is the go to guy for this stuff.

I should have access to about anything I could ask for so the oxy-acetylene should be quite helpful.

[kramttocs]

I'll be sure to be careful in removing the air pumps and system so that someone who needs it can have it. The rust all around isn't too bad and only has some real rust in the area between the bed and cab, as well as in the upper area of the footwells surrounding the tranny hump.

Thanks for the warning about being careful during removal, I might have just ripped everything to shreds:nabble_smiley_tongue:

Sometime run a water hose through the cowl and watch inside. Leaks up there are one unfortunate cause for rust at that seam.

 

[ArdWrknTrk]

When I first saw the louver I was a little confused as to what was going on:nabble_anim_confused: but now it makes sense. Probably just to be an indicator or help with heat.

Is there a big difference in lift and duration between the RV and towing cam? I'll definitely be doing a double roller and recurving the distributor as I've seen recommended and done many times. I've heard Scott/TheMadPorter is the go to guy for this stuff.

I should have access to about anything I could ask for so the oxy-acetylene should be quite helpful.

Not a 'big' difference, but you might have a more aggressive profile or slightly more lift with a towing cam.

RV's don't really need to get anywhere quickly and their aerodynamics mean they are pushing harder the faster they go.

With 3.55's running out of top end shouldn't be as much of an issue for you as it is for me.

These gearboxes have a deep enough first gear that it shouldn't be an issue getting a load moving.

If I was towing heavy and had to start on a hill with a car behind me at a light, I might be glad I have the 4.10's I do.

As it is I only use 1st a couple of times a year.

Sometimes just to show someone I can walk faster than it idles along.

I have had both 4160 and AVS carbs on my truck.

While Gary may have a personal, and long outdated bias against Holley.

Blue bowl gaskets and Powervalve blowout protection have been a standard feature since 1991.

I don't think you'd ever want a mechanical secondary "double pumper" in a heavy truck.

Didn't even prefer one in my '85 Mustang.

In Edelbrock I have a slight preference for the Air Valve Secondary over the Aluminum Four Barrel.

But this is mostly down to how it meters, and ease of adjustment.

Those flare nuts on the air injection are very likely frozen.

But not even corroded steel is frozen when it's molten. 😉

Get them glowing good and work them forward and back, they will usually come off in one piece.