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I am totally not versed on carbuators, so here goes...I have an AED 750 double pumper carb...when I floor it (just sitting in the garage engine off of course) it seems like the carb opens fast about half way and then slowly opens the 4 barrel part to kich in...When I do this by hand at the carb it does the same thing...i am not sure if the "second" part or the opening of the 4 barrels where the gas squirts into the carb is called the secondary? but regardless it just doesnt seem to open fast enough. When I mannually open it, on the right side of the carb (passengers side) i can lift up on the actuator that squits the gas into the carb and at the same time pull the lever to test the speed and it seems to open much faster. Almost like the pumper in the back half of the carb is preventing the secondarys from opening faster...not sure if that makes sense...is this carb operating correctly?

Thank you in advance of any help!

I would have to say yes...the carb is operating as per design.Typically with a double pump..you have no secondary activation until about 40% throttle angle on the primary side.The secondary throttle shaft is now mechanically linked to the primary throttle arm and will roll open with any more primary angle introduced.It takes some effort to roll open the secondarys and deal with the force applied to the secondary pump cam and preload spring.Do your underhood test again..but with more effort,as in pull it to wide open throttle with some authority.

Ditto. Also there are a couple different linkage ratios for the secondaries to change how soon and how fast the secondaries open. At least on Holley's. I don't know about AED as I have no direct experience with them.

Thank you for the info...i guess my concern is that i have a somewhat modified 350 motor in this car (larger cam, MSD ignition, roller rockers, headers, etc) and it just doesnt seem to have as much power as i thought it should have...this may sound strange but i cant do a burnout or even chirp the tires by punching it...maybe it is the timing on it too...i also seem to get like a hesitation when i get on it. but it does seem to have a good deal of power past the hesitation and seems really aggressive when i get on it. maybe i need nore practice on doing burnouts...lol.

Hmmm..... it does all sound like it's working correctly, as far as that goes.

For the response, getting rid of the bogging, and generally tuning her up right, I highly recommend a good dyno tune. Not just a pull or too for some feel good numbers, but multiple pulls with real tuning of the ignition and carb. I'd guess a half a day @ $100 per hour plus parts would be typical. Go to a good shop that does real musclecars, not a ricer or mustang shop used to dealing with efi.

As for doing burnouts, line locks are fun. Lock the front brakes and hold the button, smoke em down to the rims if you want!

Interesting concept... :) I like that...i was trying to find a place to buy it and checked like Jeggs, Summit, Ebay, etc but cant find one specific to fit a 68 Camaro...I did install power disc front brakes on mine so not sure if that matters...would i just buy a kit and adapt it to my car or is there one specific to fit the 68 Camaro?

thanks!

There is a thread here that Don did, mostly asking what to buy.

It's an electric valve that you insert in the brake line for the front brakes, and a button, normally attached to the gearshift on a stick car, nearby on an auto. You step on the brakes, then press and hold the button and release the brakes. The closed valve does not allow the pressure to bleed out, keeping the front bakes locked as long as the button is held.

Install is making a couple new brakelines, finding a place to bolt down the valve, and running a couple wires.

I got pics and such to make a thread on how, I'll try to do that. You new guys are great, getting me off my ass and adding some good content to our site. And yes, we can say "ass" here.

another question somewhat related...is there a "basic" number as far as timing on a motor with a larger cam in it? It has the AED 750 double pumper with the MSD ignition...everything I find on timing seems to relate to the older points style distributors...there is no vacumn advance so i cant plug the vacumn line...just wondering what this should be set at...right now when i put the timing light on it i am probably about maybe 18 degrees...i bumped it up to about 20 and it seems to run a little bit better. hard to tell exactly where it is at since the indicator tab only goes to 16...

Philip,
Here is a Tech article that explains ignition timing in great detail......

Ignition Timing

David F

nevermind...found out what i needed to know at this site... http://www.msdvideos.com/video_detail.php?mId=8381

Thanks!