86 f250 HD intake/exhaust question
 

Hey all,

working on swapping out the freeze plugs today and wondered if anyone has put headers on their 460 in this truck since I pulled my mainfolds to get easy access to the plugs. Mine is a HD model with no cats and the mainfolds are stock, about the size of shorty headers..

but all of the headers I see for my truck look like long tubes which would require me to change the exhaust, which I don't want to do..anyone got stock size headers for this truck that aren't longtube length that would bold right into the ypipe, exhaust? (make sense?)

also, since my truck is the HD model with no cats and original a 2bbl from california (yes 2bbl), what is a good intake/carb combo that is basically a bolt on for what I have..truck is primarily used for towing my boat or dump runs..nothing much else.. I have a c6 4x4 too.. Thanks in advance, you all have been great!

Keep looking but you have your thoughts in the correct direction...if you can't find shorties to fit, just keep the stock exhaust manifolds. The fit problems with the exhaust underneath the truck are not worth the gains with long tubes in my opinion.

With the carb/intake, stay small. Around a 600cfm with vacuum secondaries, and a conservative dual plane low rise intake. Most 460's had 4bbls as you know, and I would not hesitate to get one of those intakes at a good price and use it. I would get a new carb though. Too many vacuum ports to plug off on the original 4bbl and it was mainly a emissions carb.

cool
 

Yeah, stock mainfolds on mine have no emissions stuff so that's a plus..wonder if you could extrude hone them like and intake to improve flow? Probably cheaper than aftermarket set..?? Besides, the overall exhaust is in good shape so I can't see messing with it..

I was fortunate enought to get one of the holley 4180 carbs. from a forum member here and was going to rebuild it but was also told that it was a hassle because it was an "emissions" carb?

then I was told about the eldelbrock 1406 and have heard they are good also? I really want the easiest setup for my truck... so you're saying just to get a stock cast manifold and throw the carb on it? 600 cfm was all I was looking at..no need for any bigger for me :-hair (never though I would say that, lol)

You've got the manifold, any "spread flange" (Holley pattern) 4 barrel will fit. I have never been a fan of Carter carbs on Fords, unless it was the Lincoln 430 which had a huge AFB on it from the factory. If you really want decent performance, go with one of the 735 cfm Holleys from a 1969 428 CJ.

The 4180 from what I read is a great carb and not much different from the non-emissions carbs. Just make sure you get the correct rebuild kit as there are some changes like a two-stage powervalve. You wan the holley 3-1346 kit.

As for shorties, I don't think you're going to find anything specific. Sanderson has some shorty headers for older trucks that will likely work but you'll be adapting the lower pipes to work.

Bill-
Thanks for the mainfold, she's sitting on my counter with the carb on it.. will probably take the manifold to the bead blaster and clean up the outside.. any thoughts on how to improve the inside? Extrude hone?

f100- thanks for the kit #, I have seen several diff. types and wasn't sure which one to use..


-Oh yeah, is there any way to remove the motor mounts from the truck w/o removing the motor to get to the center freeze plugs on a 460, or should I just pull it?? ugh...oh yeah, gotta flush the cooling system because the new fluid I put in after discovering the leak has been in there for about a week and it's rusty looking too...:-X18

one other thing, the exhaust flange bolt from the manifold/header is rusted to the point I broke my craftsman universal in half at the socket connection!!

I have access to the flange with the dremel and wanted to know if I cut the bolt off would I be able to have a new bolt installed in the manifold so I can put the flange/exhaust back together? Or is this a bolt that's molded into the mainfold??

It should be a stud but if it's that rusted you're going to have a hell of a time getting it out. My suggestion would be to heat the manifold red hot with a oxy torch and then loosen the nut. Don't cut the stud if you don't have to. This should take the whole stud out. Then you can get a new stud with a brass nut.

Look at the manifolds I gave you to get an idea.

If the stud breaks off, you can center punch it and drill it out. You may have to take the exhaust manifold off though if you have no room to work.

Usually with the motor mounts, you can take the fan shroud loose, take the motor mount bolts out, and then get a solid piece of wood that GOES ALL THE WAY OUT PAST THE VERTICAL EDGES OF THE OIL PAN and jack up on the engine to raise it up. Of course if you have a engine hoist, you can lift it up a couple of inches with that.

What are your intentions with this truck? You are correct, improving airflow will increase the power output, but it won't do you much good if you are towing a heavy load down the highway at 1500-2000 rpm.

Amen, 10.5 mpg empty, 8.5 mpg towing a 10,000 lb 5th wheel.

Appreciate the help
 

As far as the manifold, it's a stud and a torch would be necessary for sure to loosen it up enough to try and get out.. may have to cut and then drill the stud out.. thankfully I pulled the manifold when I put the freeze plugs in sunday, with the exception of the ones behind the motor mounts.. :-arrgh

I do have a motor hoist and wanted to know if it would be better to put a lift plate on the intake or just get some chain and attach it to the block on each side where the manifold bolts went it..putting the bolts and large washer through the link and hoisting it up that way? (which I think may be easier)

I saw the two bolts connecting the motor mount to the frame and they look easy to get to, hopefully and aren't rusted. Should I remove the tranny crossmember bolts also so the tranny can lift up with the motor?

Franklin, I plan on using the truck around town and to tow my boat and make dump runs. But eventually would like to restore totally like my old 83 F250 XL and put 35 inch tires on it..

You can lift the motor up with a couple of the bolts through the chain like you mentioned, have done it many times before.

I would leave the rear mount in place. You are only going to lift the engine a couple of inches before things start hitting, like the bellhousing against the cab. It won't hurt the rear mounts by leaving them connected.

Ryan, you will find the nuts are the "prevailing torque" style and will fight you the whole way.