318 4 bbl install and linkage questions

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7374

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alright guys I installed an Edelbrock Manifold and holley 4 barrel carburetor. I also bought the Holley carb bracket and rod. I could install the kickdown bracket using the stock throttle cable bracket/mount With no Issues. the only problem was that the throttle cable would not reach the carb. so I purchased a aftermarket high rise intake manifold Throttle bracket. this now moves the throttle cable to the right position so that it will reach the carburetor but I have no way of now hooking up the kickdown linkage. this new bracket has provisions to use a lokar kickdown cable. should I just buy the new kickdown cable or does anyone else know of a way to make the stock brackets work? please provide detailed pictures if at all possible once I get in front of my computer I will upload pictures of what I have currently.
thanks in advance!
 
Hmmm.... when I swapped out the two barrel manifold to a 4 barrel Wieand intake and Summit street strip carb, I just swapped the bracket from a 4 barrel car on there and everything fell into place.
 
Bad Sport is correct. Need a 4 bbl bracket to start.

Pics will help.
 
Hmmm.... when I swapped out the two barrel manifold to a 4 barrel Wieand intake and Summit street strip carb, I just swapped the bracket from a 4 barrel car on there and everything fell into place.
That's what I did back in the day when I went to a 4 barrel carb on the 318 .
 
Throw a wanted ad on here for a 4 barrel throttle bracket. I bet that cures your issues.
 
Actually now that I think about it, it was the rod from the pivot to the carb linkage.
 
Mancini racing sells repro 4 bbl throttle brackets new.
 
I got a 4 barrel bracket from a 79 New Yorker 360, and I can't get it to line things up on a performer with either an eddy 600 or a TQ I wonder what gives with that.
 
Spelling might be wrong; Bouchillian. Have used them, very good, and perfect customer service- the owner will call you back.
 
I changed from 2 bbl to 4 bbl also. I've made a throttle cable bracket that fixed the throttle cable and I extended the throttle pressure linkage that is hooked up to the carb. I have 0.24 inch (6mm) to much at the throttle pressure linkage rod to throttle stud at WOT. Everything else is right where it should be but I have read that the 2 bbl have more travel then the 4 bbl so the geometry is probably diffrent. Does anybody have any idea to solve the problem without changing to 4 bbl bracket or Lokar cable?
Thanks FABO
 
Way back when I switched to 4bbl on my 318, I've kept using the 2bbl bracket for the kickdown and made another bracket for the throttle cable. I've since incorporated the two by just using a stand-off for the throttle cable, but I think a 4bbl bracket would make it all easier to setup.
 
I just modified 2bbr bracket when swiched to 4bbr intake and summit carb. I also had to modified kickdown linkage to work whit new setup. I have driven about 2000 miles and no broblems whatsoever
 
Sent a PM your way, Pompis, but I posted this here for anyone interested in doing a 2bbl linkage on a Street Demon.

Demon%20Carb%20linkage%20finished.jpeg


If you don't get the arm extended 1" up, it will not engage kickdown completely.

What I did, was set the throttle cable out from the bracket about 1 1/2" on a piece of 2" 3/16" flat stock and put the cable hold down hardware out;

linkage%20mod.jpeg


If you use your A body cable you will need to set it out and forward to reach and make an L shaped extension or taper it forward (straight flat stock, but longer at an angle- / ) instead of the straight one that comes straight out to the side, like I made. I used a B body cable. The cable will go above the kickdown linkage.

I also made a 1 1/2" flat stock piece with holes 1" away from each other, to bump the kickdown up, on the linkage at the carb, with a 1 1/2" bolt and two nylock nuts to kick the linkage out, so it wouldn't bind on the rest of the linkage below, at higher throttle positions. You can see that in the first pic.

I bent the kickdown linkage arm with more of an elbow, and bent it out, then extended it with a threaded sleeve and bolt that I trimmed the head off of to reach the raised arm.

Demon sells a throttle linkage pin that uses throttle pin for kickdown, while an original will work in the same spot if you just drill the linkage, you will need a shorter arm on the trans to do this, or it will nuke your clutches and steels in the trans from having too low of pressure. kickdown linkage has two functions;

-downshifts
-controls pressure from trans oil pump to clutch engage pistons at all times

When I put the throttle cable and kickdown on the same pin, where Demon suggests, the kickdown only engaged 3/4 on the trans lever.

I would have picked up a Lokar kickdown cable, which has multiple spots on the lever at the transmission and will use the same pin as the throttle cable, or even a shorter lever at the trans, to counteract the short throw on the Demon linkage, but I'm ditching everything in months to come for a stick shift, so it's all going away, so I did this on the cheap. Everything shown clears a stock drop air cleaner with no mods or risers.

Do it however you like, but just remember, it has to engage completely back at the trans, at wide open throttle on the carb for adequate oil pressure at the clutch pistons to hold under the torque input by the engine at different throttle levels.

Hope this helps anyone going after stock 2bbl to 4bbl Street Demon install.

If I had to do it again, if I was going to keep the auto trans, I'd go with a Lokar setup and use a short lever at the trans to eliminate putting the kickdown and throttle on a different axis.
 
Thanks Dave for that explanation! Did what you explain and made a flat stock piece with 1 inch between the hole for the kickdown and it didn't work at all. The geometry was way of. But with your explanation my side to construct things kicked in and solved it like this:


I had already made a bracket for the throttle cable like this. The flat piece for mounting the throttle cable is slightly angled downward.
DSC_1791_zps1873abaf.jpg


The kickdown rod(throttle pressure) I extended with a round rod that was 1.38 inch or 35mm. Cut off the kickdown rod where it had that elbow angle and welded the round rod piece together so it became extended outward too. It has no angle execpt the extended piece.
DSC_1792_zps9d168e0e.jpg


Cut the 2 bbl throttle and kickdown stud where the threads ends.
DSC_1795_zps2c1d3e67.jpg


Took with the angle grinder 0.06inch or 1.5mm on the throttle stud nut. Then I cut of a bolt to extend what was left of the kickdown stud.
DSC_1794_zps4af567da.jpg


Welded it together so it looks like this.
DSC_1796_zpse588f14d.jpg


This is how it looks finished. It works like intended and have 1/8 inch end play now. Going to grind the kickdown rod and stud to make it look smooth and then paint it.
DSC_1797_zps8d0ff728.jpg


But thanks Dave anyway you gave me insight how to modify the geometry.
Hope this can help anyone also.
 
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