I did a search, but came up empty. I've found some decent looking Headman headers online, but have heard of fitment issues with them. Is it worth installing headers with the stock intake and single barrel carb?
If I do this, I assume I will have to make a custom plate to block the hole in the bottom of the intake where it attaches to the factory exhaust manifold.

Any advice is appreciated. I don't mind grinding, cutting, welding. Just looking for the best option here.

 

I have never put headers on a 300 but am currently building a 300 for my 66 and I went the route of putting the later split efi manifolds on. They flow way better than the stock manifold and can be picked up cheap. My opinion is unless you are trying to make lots of power headers are not worth it over the later efi manifolds and seeing how you are keeping the stock intake and carb probably not worth it. But I would get a set of efi manifolds if you can find some cheap. You shouldn't need to make a plate to cover the hole where the two attach (doesn't go through to the intake just allows exhaust to blow on intake to heat it.)

 

I was thinking the same thing. The stock 65 manifold is very restricting, and inefficient. The later split manifolds are a definite improvement. Either way, I will end up going into two separate pipes instead of one, so I might as well make the switch to the headers now.
I do plan to change the intake and carb at a later time. It would be nice to find a full kit. (Headers, improved intake, and improved carb)
This is needed, as I am planning to install a M5R2 five speed. Might as well improve the breathing now.

Thanks for your reply. It's a good suggestion if your're staying with the stock intake and 3 speed. I did not know that about the intake.

 

A friend of mine put a rebuilt stock 300 in his 65' SB and installed a 4 barrel manifold with a 600 Holley with vac secondary. He matched that up with a set of headers. All stock parts inside the motor. Got to tell ya, that thing is fast. Incredible what a few add-ons can do. You get to ride in it, pretty hard to believe it's a 6. Course I remember when it was common place to see hoped-up 6 bangers in Hot Rods. :-)

 

Having done numerous 300's, the Hedman headers are worth it. A big thing on the 300 is a good cam, makes a HUGE difference.
I used these headers
http://www.summitracing.com/parts/he...view/make/ford
http://www.summitracing.com/parts/of...view/make/ford
and this intake with a Holley 390, elec choke,,, with an NP435 and 4.10's I could stay at 16+ mpg if I kept it under 60, and when you hit it, it would go!

If possible I would try to do them both at same time, intake and headers, but if not, no worries. I haven't been totally thrilled with the EFI manifolds, doesn't seem to have as much low end as the long tubes,,, I currently have the EFI ones on my 79, and would prefer the Hedmans.

Put a NEW starter in at time of header install,,, just saying,,, been there done that, to install headers, remove starter, when headers are halfway in, i.e; in place, re-install starter. If/when starter dies, you will have to remove headers, buy an extra header gasket or two also, and also extra collector gaskets. It sounds awesome when you have the split manifold sound!

I did the 2 into 1 exhaust when I changed out the glasspacks,,, HATED it, went back and had them go back to true duals, exit behind the wheels,,, just a loverly sound!

Also, depending if you want, I did the headers wrap the second time
http://www.summitracing.com/search?S...=header%20wrap

it DRAMATICALLY reduces under hood temps and those pesky burns you might occasionally get from "HOT" things. I highly recommend it!

 

Before I saw these replies, I couldn't help myself, and dropped the $ on the whole kit from Jegs. Got the Holly 4 barrel, Offenhauser intake, and Hedman Hedders, all together. My wallet hates me, but oh well. Can't wait to get this stuff in. The intake is on back order though.

Going to run this setup for a while before deciding on cam upgrades.

 

Can I ask a simple question, since I don't know a lot about this, but interested in the topic. Don't you need to heat the intake somehow for the fuel/air below the carb, and don't you eliminate that by removing the stock intake and exhaust, and using the Offy intake and some headers? Does that mess things up, or doesn't it matter?

 

The heated intake is just the help the engine warm up faster. As far as performance goes, vehicles always run better with cool intake supply. This new setup will improve performance, but increase the amount of time it takes to get the motor to warm up. I will probably have to switch to a higher temp thermostat in the winter.

 

You might want to read this. If you can get away without then fine, but if you have issues this might help. Some people even get too much heat from the headers.


https://www.ford-trucks.com/forums/1...ires-heat.html


and this


http://www.langdonsstovebolt.com/tec...take-manifold/

.

 

In my 65 I have a 96 f-150 longblock (4.9L/300) with the fuel injected split manifolds. Going into a walker y-pipe 45166 I believe. I'm new here so I don't know how to post pics yet.

 

Here it is.<br/>

 

Looks sharp hipdqwik1

 

Thanks! I'll dig up some more pictures soon of my setup.

 

I was gonna use the 4 barrel intake with like a 390cfm holley but it seemed there was a lot of difference in the runner size and length.

I found Clifford Performance's dual intake which allowed me to use 2 Holley 2 barrels from the 70s fords. (Licensed/copied from Weber 34/36s).
I liked the idea of having coolant passages in the intake along with the better fuel distribution. The carbs have baby primary and secondaries so it might not be so bad on gas.

 

Looking at your setup sure brings back memories, 300 +0.030, 12.5:1, Dual Holley 2 brls. Big solid cam, and Methanol, in a 1800 lbs. dirt modified. Exciting!