2 BBL to 4 BBL conversion - linkages to change?

EurekaSevven

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Hey all,
A few days ago I took a roadtrip to get two parts I needed - an electronic voltage regulator, and more importantly to me, a "301" 4 barrel intake for my 1968 383 engine, which just currently has the factory 2 barrel intake.

Talking to CBODY67 in DMs and doing some reading on this forum and others, it seems some of the linkages need to be replaced for this conversion - as the 4 barrel carburetor's linkage stud is positioned slightly different than the normal 2 barrel. I believe it was the throttle linkage needing to be a little bit longer, and the kickdown rod for the transmission being different - along with the springs (green instead of red, if I remember).

For anyone with experience, is there anything else to consider, and if I listed all of the differences right, how much longer would the throttle linkage need to be compared to the 2 barrel one, along with the kickdown rod (I've heard that the 2bbl kickdown rod can work as well, I have the original "threaded" one from the factory). Anything on the bottom of the trans I need change?
 

Davea Lux

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You need to specify which carb you are going to use. Edelbrock and Holley both have linkage adapter kits for the throttle cable setup. www.bouchillionperformance.com makes the kick down adapter to go from 2BBL to 4BBL. Lokar also makes a similar kit. Jegs and Summit racing usually have the kits in stock.

Dave
 

EurekaSevven

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I was planning on using one of the original Carter AVSs, assuming I can find a good core, but if nothing else than an Edelbrock AVS 650.
I'm guessing the kit you're referring to is the "BPE TorqueFlite Kickdown Cable Kit (3350)"?

But in the case of using the OEM Carter AVS, would anything special need to be done with that in that situation, more-so if it already has the Chrysler carburetor throttle stud on it?
 

Davea Lux

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I was planning on using one of the original Carter AVSs, assuming I can find a good core, but if nothing else than an Edelbrock AVS 650.
I'm guessing the kit you're referring to is the "BPE TorqueFlite Kickdown Cable Kit (3350)"?

But in the case of using the OEM Carter AVS, would anything special need to be done with that in that situation, more-so if it already has the Chrysler carburetor throttle stud on it?

The kick down linkage will still probably not be the right length, if you do not want to spend a hundred bucks or better on one of the kits, you can scavenge the 4BBL kick down parts for your local Pick & Pull for about $10, if you can find a similar car. If memory servers me correctly, the kick down linkage should be the same from '68-'70. If you go that route, be sure to grab the lever for the kick down from the transmission as it think it was also a different length.

Dave
 

69 300 vert

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The kick down linkage will still probably not be the right length, if you do not want to spend a hundred bucks or better on one of the kits, you can scavenge the 4BBL kick down parts for your local Pick & Pull for about $10, if you can find a similar car. If memory servers me correctly, the kick down linkage should be the same from '68-'70. If you go that route, be sure to grab the lever for the kick down from the transmission as it think it was also a different length.

Dave

'69 started the fuselage era with the one piece kickdown linkage, no way it'll work on a slab side. IIRC, a bit of cutting and welding on my brothers '68 got it fitted up. Not as pretty as a factory 4 bbl piece, but it worked. Throttle cable and linkage can be adapted, don't recall sourcing any other springs but do believe the factory used different springs for the 4 bbl.

If I were doing it today, I'd probably just point and click here:

BPE TorqueFlite Kickdown Cable Kit - Bouchillon Performance Engineering
 

EurekaSevven

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Throttle cable and linkage can be adapted, don't recall sourcing any other springs but do believe the factory used different springs for the 4 bbl.
Do the throttle cables have a different length between them, or are you saying the 2bbl is usable with the 4bbl with no modification?

The BPE Kit looks like it might be the easiest route to do it, although I wonder if a member here has the parts laying around somewhere, willing to sell - might be work making a thread in the sales section to see.
 

furious70

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On a fusie at least I've used 2bbl kickdown on 4bbl by using a small nut and bolt as a stop in the slot to get correct engagement
 

69 300 vert

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Do the throttle cables have a different length between them, or are you saying the 2bbl is usable with the 4bbl with no modification?

The BPE Kit looks like it might be the easiest route to do it, although I wonder if a member here has the parts laying around somewhere, willing to sell - might be work making a thread in the sales section to see.

Yes, no need to change cables. Factory may have used a different cable but the 2bbl cable works fine.

If somebodies got one and willing to sell it, that's the way to go. IIRC, the 2bbl kickdown is too short, I think once we spliced in a short section? It didn't look as nice as a factory piece though it worked fine.
 

EurekaSevven

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I didn't want to make another thread, and this one is still related enough to ask the question:

I got my 4 holer intake mounted, and more or less every bolt is ready to be torqued, but the 2bbl throttle bracket doesn't seem to engage with the 4 barrel intake properly - I'm assuming they use different brackets for each intake?


I saw the red ones for sell, that look like this:
JP-61098-2.jpg
 
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