The Stovebolt Site Forums The Shop Area The HiPo Shop Carb linkage for a four barrel

Anybody have any trick ideas for carb linkage? I have an Edelbrock 4 barrel on my 270 GMC. I looking real hard at using a Lokar cable to the bell crank, that way I can still use the stock gas pedal and rod to the bell crank.
Any ideas would be mucho help!
Thanks Bolters

That's exactly what I would do.

Check out the tech tips here on the stovebolt and on www.inliners.org for two ideas.

Personally, I like mechanical linkage. When I installed a 2 bbl and then a 4 bbl on my 292, I used the same principle and most of the factory linkage. The factory linkage more or less just pushed the carb open with crank/arm that rotated up/down - vertically. I fabricated a bracket and used the same crank/arm in a horizontal position to push the carb open. Now it works side to side instead of up and down. May be easier than it appears to slightly modify the stock linkage.
What's a 270? Is that a V6?
If you need a hand, I'm in San Diego also. Just shoot me an email.
-David

270 is a GMC straight six, and a darn good engine.

Thanks Bolter's. I'am going with the cable, easy,clean, and simple add its S.S. so it looks bitchennnnn.
Thanks for the help.

Linkage is often an issue when using a non-original carburetor; but it needn't be. The big problem often seems that the linkage one has works in the wrong direction for the different carburetor.

To change linear direction (from "push" to "pull" or from "pull" to "push":

Make a metal arm twice the length of the distance from the mounting hole in the throttle arm to the throttle shaft plus 1/2 inch. Drill three holes in this metal arm. The first should be the same distance from the center of the arm as the distance from the mounting hole in the throttle arm to the throttle shaft. The second should be exactly the same in the opposite direction. The third (and a corresponding hole in the original throttle arm where it is convenient to insert a screw). Now affix the new arm to the original throttle arm using the two holes on the same side of the arm, and affix the throttle linkage to the third hole. The throttle with this arm should now function like a child's seesaw (when one child goes up, the other goes down).

To change direction of 90 degrees (a right angle):

Make a metal arm in the shape of the capital letter "L". Drill three holes in the arm; one at the end of each leg, and one where the two legs join. Attach the arm with a loose double nutted bolt to some fixed point on the engine using the hole where the two legs join. Point the two legs away from the two linkages, and attach each linkage to one of the legs. Moving one linkage will rotate the "L", causing the other linkage to move at a right angle to the first.

Once these concepts are learned, any hobbyist should be able to fabricate his/her own throttle linkage.

And two pictures would be more useful than all of the previous verbiage in this post! If this post is confusing, and you wish clarification, give me a call during normal business hours.

Jon.

Here's how I did a mechanical linkage on my 37 PU.I first tried a Lokar cable of the original throttle pedal bellcrank on the side of the block. It worked but the cable had too much fricton,required a pretty stiff return spring. Removed the stock linkage,put in a typical hot rod pedal,made up the rest from a discarded GM linkage.Hardest part on an inline engine is making up brackets,I mounted the bellcrank on the intake. It all works smoothly with a light return spring.
home made linkage

I hope this link works. Can somebody let me know if it doesn't?

http://photos.groups.yahoo.com/group/kustoms-and-sleds/lst?.dir=/mugsy%27s+292+setup&.src=gr&.order=&.view=t&.done=http%3a//briefcase.yahoo.com/]my 292 linkage

I used 2 pieces of flat bar, 1" wide and maybe 3/16" thick, welded them in a V shape and drilled holes in the ends for the carb mounting bolts. I mounted the V to the two rear mounting bolts. Next I welded a piece of round bar (at a slight angle which I discovered worked best during mock up) at the other end of the V and mounted the stock 1 bbl crank and arm on it. I drilled holes and used hitch pins to secure it. It's important to figure out all the sweet spots during mock up where the linkage seems to work best and move freely. I measured 4 and 5 times before cutting or drilling. Aside from my welded V with round bar attached to it, it's all stock linkage just working horizontally instead of vertically.

Dave, I'd really think twice about the cable. I don't think I've known anybody who liked their cable or thought it was better than mechanical. I had a cable setup once and it sucked!
Good luck either way and my offer to help still stands. Just drop me an email.

Mugsy - tried to fix your URL. Wouldn't do the exact right thing but at least it links now. But it goes to a Yahoo log on page. Is there where you wanted it to go?

Peg

Thanks Peg, I think you've gotta be a member of the group, I wasn't sure. I'll try to upload them elsewhere and do another link.

OK, try these links for the above post:
carb linkage
carb linkage 2

Ok Mugs, I see what you did now, ok. This is a crossover linkage on my 51 powered by a 261 with a 2300 Holley 2 bbl on a modified stock intake using the stock throttle linkage. Just make sure the linkage arms don't go over center and operate without binding of causing the linkage parts to take extreme angles resulting in binding.
Holley 2bbl on stock intake