All Small Six Performance question

This relates to all small sixes

CWT1129

Well-known member
Hey guys, with my 65 Mustang, if I add dual outlet headers with dual outlet exhaust, do I need to upgrade the carb to 2 barrel right away or can I wait? I would like to do a slow build!
 
straight headers typically give 5, 8% increas. w/these engines.
(ur post "performance")
Most are for looks/sound (the 2nd w/good choices).
Pretty inexpensive (140/70$) these daze (cept cj pony)~
 
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Install a 68+ distributor with centrifugal + vacuum advance first.
Plug the venturi advance vacuum in the Load'O'Matic Autolite 1100 with a dap of expoxy.
Then install the header.
 
I have a 200 with small log. Was thinking dual headers with 2 or 2 1/4 inch exhaust. Clifford performance suggests the headers with 2v Weber 38/38 carb with adaptor. Distributor is a must for 2v carb I would imagine?
 
Any engine performance mods mean ditching the LOM distributor for a 'standard' mechanical advance distributor with vacuum advance, or programmable ignition, so it is tunable for proper timing. This is true for the Autolite as well as any other carb.

X or H is personal preference, and both perform well in testing. I like the tone of the H myself. The X is 'raspier', relative to whatever the rest of the system is, of course.
 
2 1/4 pipes headers back is my plan!
My car came with a 250 head. I added a Weber 38, headers, and a 2.25" exhaust as well as an HEI distributor. It's made a huge difference. I did not put in a port divider. I read up on them and there is no consensus that they actually provide an advantage. The next step is pulling the head to check everything and looking into milling it down to bump up the compression along with some porting/polishing.
 
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250 head is on my radar. Right now just hoping that I make the right choice for the exhaust in regard to sound. Did u do X or H pipe? How does it sound? Any issues installing the headers. What has to be removed?
 
Can I do it without pulling the head or engine?
Can you do what? I had to pull the starter to get the headers started, and then slipped the starter back in beneath them. It wasn't a big deal.

I used the headers from Vintage Inlines and one of their exhaust systems. It's a single exhaust pipe back and over the rear axle. It's ok and sounds pretty fair, but I'm not thrilled with the fit. I wanted my car to look stock and didn't want a dual setup.
 
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Yes I remember you saying that. Same size starter or did you switch to the 144 starter? I have seen people say the headers might fry the starter. Alternator clearance issues? Throttle linkage modifications? Sorry for all the questions, just a little nervous about doing this. I am using the Clifford headers!
 
Yes I remember you saying that. Same size starter or did you switch to the 144 starter? I have seen people say the headers might fry the starter. Alternator clearance issues? Throttle linkage modifications? Sorry for all the questions, just a little nervous about doing this. I am using the Clifford headers!
I used the factory starter since a new one was on the car. I've heard that the starter may fry and also heard from folks who say it isn't a problem. A fiberglass heat wrap for the starter is available or you can wrap your headers. The stock linkage would not fit around my headers, so I installed a Lokar cable and a '69 Mustang pedal. The pedal had to be modified to fit the cable, so I welded on a tab after cutting a slot in the end of the pedal shaft to hold the tab.

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