recurve secondary

[lostforawhile]

has anyone atempted to recurve the secondary cam on the carb? most carbs the secondary opens before wot but on our carb the secondary has a cam on the throttle shaft that won't allow it to open until wot if you were to take a dremel tool or such and reshape that secondary cam the secondary throttle plate could open sooner. it's been done for years on holleys etc. thats why they make springs that can be adjusted on the vaccume secondarys. ours is just a little different. it has a second cam that makes sure the secondary doesn't need a lot of vaccume to stay open during sudden acceleration it's basically a mechanical boost for a vaccume secondary. if you have an extra throttle body around pick it up and mess with it you'll see what i mean. let me know if anyones has done it before. this could def free up some horsepower it not a bad carb it's just been configured for fuel economy.

[A20A1]

has anyone atempted to recurve the secondary cam on the carb? most carbs the secondary opens before wot but on our carb the secondary has a cam on the throttle shaft that won't allow it to open until wot if you were to take a dremel tool or such and reshape that secondary cam the secondary throttle plate could open sooner. it's been done for years on holleys etc. thats why they make springs that can be adjusted on the vaccume secondarys. ours is just a little different. it has a second cam that makes sure the secondary doesn't need a lot of vaccume to stay open during sudden acceleration it's basically a mechanical boost for a vaccume secondary. if you have an extra throttle body around pick it up and mess with it you'll see what i mean. let me know if anyones has done it before. this could def free up some horsepower it not a bad carb it's just been configured for fuel economy.

I know someone did, btw the cam allows it to open prior to wot. If you move the linkages by hand the secondary starts opening as the primary reaches WOT, not when.

Personally I liked having the manual secondary. I've never tried to adjust the opening point by shaving the cam.

Here is a pic so you guys can see what he's refering to.

[lostforawhile]

it allows it to start to open but not very far once the primary reaches wot it comes off the step and the secondary can open more. the second cam i'm refering to releases spring pressure on the secondary at wot. this is so when you get a sudden vaccume drop at wot the secondary will still open if i could get the secondary to open sooner it would be more like a weber where both barrels open at the same time

[A20A1]

It's venturi vacuum secondary... venturi vacuum is supposed to be higher at WOT.

[lostforawhile]

I know that but it takes a second to build up that vaccume, that second cam unloads spring tension on the secondary at wot that's so you don't get that hesitat.t.t.t.t.ation when you put the gas to the floor when that spring tension is unloaded it only takes a small amountr of vaccume to hold the secondary's wide open . where i'm going with the whole post is if that first cam was recurved slightly the carb would have more airflow at part throttle when the secondary was open sooner. both barrels operating sooner.