Hey every body. I have a 1978 f100 with a 300 in it. I have ordered the exhaust pipe to manifold bolts. I am trying to find the part number for the bolts. I have some by dorman but want to make sure they are the right ones before I start. I had ordered the MPC from hipo.com, and am having no luck understanding this thing. I want to understand how to look the parts up in said catalogue and how to cross reference them. I'm in need. Because I'll be lucky to get bolts out without breaking them but I'm not in a position to leave detatched as she's a daily driver.

 

I have master truck parts disc, I believe it ends in 72. Anyway it takes some getting used to, to navigate it, not easy and if you use it seldom, you forget what you've learned.

Doesn't your 300 6 use studs on the manifold at the Exhaust pipe and secure with nuts?? Unless somewhere in trucks history someone changed/modified the hook up.

 

hkpotts44,
iicap in my opinion answered your question correctly concerning your exhaust manifold.
The 300 in my 79 uses 2 studs at the flange ( i think they are 7/16 / 14 course thread on one end and ?? machine thread (fine)
on the other end and total length of 2 1/4 in. long...
Dorman part number I have is 03099 the package comes with 3 studs 3 brass nuts and lock washers..
We know the 300 only takes 2 studs but that package probably fits many different engines.
Problem I have found working on these old trucks is like iicap mentioned, there have been lots of different mods and parts used on these over the years.
Sorry I don't have an answer for the parts catalogue to your original question.
Attached is a picture of power steering resavore modification used over the last 42 years.. LOL
Oh yea, also I use plenty of antisize.....

#ad

 

Now that's innovative thinking, Mac Giver-ized.

 

Sorry I've been at work last couple of days.

They are studs sorry called them bolts in a rush.

My MPC disc says its for 1973-79 ford truck series 100/500 and then I ordered one for my 1979 dump truck,acquired last weekend for $500 , and it says 1973-79 ford truck series 600/900. I haven't tried looking at the medium duty truck MPC to see if its any easier to understand.

 

That picture made my morning. No They are studs I apologize for the confusion. That is the package of studs I got from Dorman I was confused because it appears to be the regular two and then a lone stud holding the intake to the exhaust part of manifold. I'm gonna go see what i can get done before going to work and delivering pizza to the nice tourist of North Myrtle Beach

 

Glad that picture was inspiring>>>>lol
I purchased that truck from a farm in Ala. He purchased it from the original buyer in Ga. which used it on the farm and hauling live stock to market.
This was to illustrate some innovative procedures used on these old trucks. What iicap was saying is very true, I have found wrong pulley's bolts where the hole has been drilled and tapped. Over the years, your exhaust manifold possibly could have been tapped for different size studs.
I always pulled it apart and then found what I needed.
Being it is your DD, that would be tough one.
Good luck

 

HKP44, not following you completely. F-100 has a dump body? that's OK.

IF the 300-6 was still available in 600 thru 900 trucks, I'm not sure, but, older ones used a center drop exhaust manifold with maybe 2 1/2" or bigger exhaust pipe with a 3 stud flange. You may have picked the studs for the bigger manifold. Not sure if studs for big manifold are same as 2 for F-100/150

Should something like this

https://www.ebay.com/itm/274885431439?hash=item400072d08f:g:Y84AAOSwC5xg9Xg4

 

The inlet pipe is attached to the manifold with studs and nuts, not bolts. These parts were also used on V8's.

You have to look at the illustration of the exhaust system, here:

1973/79 Ford 100/500 series Truck Parts Catalog ~ Illustration section 52, page 35.