Well I took my car in for a dyno run this moring. I was very disappointed in my results. It wasn't too bad on torque but just died on horsepower. These were taken at the rear wheels:
198.2 HP @ 4250
401.4 ft. lbs @ 3300
Not until after it was done did the tech discover that my secondaries weren't opening. . Guess I have a new project for tomorrow. Anyone have a guess on what my Hp will increase when I get my secondaries to open?

 

I'll make a guess...after you tell me how long a piece of string is.

 

When I saw "Dyno Disaster" I pictured a fresh engine on the dyno with a con-rod sized hole in it and a big mess on the floor.

Secondaries not opening are a long way from a holed block. Are you going to start a pool on rear wheel horsepower once you get your carb worked out? I'll buy a square, say the 275 to 300 HP one? Cheque's in the mail...

 

You might be surprised at how common that is.... there's no telling how many racers have got beat at the track from a throttle that didn't open all the way after a carb replacement or whatever.

I'd expect about 30-40% more HP with the problem corrected. Look for something in the 260-275 range at the wheels.

 

Well, I can't say how much the HP will increase with the improved carb tune, but if your numbers are correctly posted, you were already at 252.2 HP@ 3300 RPM. So, it is strange that the Dyno reported the lower 198.2 HP at 4250 RPM.
Let us know how it goes!

 

Well to me this was a disaster. I was expecting atleast 375-400 at the crank. I pulled apart the carb today. Its a piece of crap, guess thats what I get for buying used parts on ebay. Fix one vaccum leak and two more show up. I'm just gonna wait till I can afford a new one. I really wish it was working correctly, because I'm moving to N.C. on Monday. Now I gotta drive my half- *** carbed camaro across country. And yes those numbers are correct from the dyno. Actually they do it by speed, like 198.2hp @ 90.0 mph and 401.4 @ 69 mph.

 

Was your converter locked up? I've heard that non locked converters can cause really high torque numbers but low horsepower numbers when on a chassis dyno.

 

rebuild kits are alot cheaper than new carbs...Im guessing this isnt a mechanical secondary carb

 

3GC you're right about the converter not locking. It always runs like **** when I lock it. Feels real jerky and lots of power loss. And the sec. are vaccum. I'm thinking about getting the Proform race series 750cfm carb. I'm done screwing with vacuum stuff. Unless someone wants to donate new carb

 

Yup all mechanica for me......just get the intake to match. a dual plane for sure. On a street car!

 

If the car jerks when the converter is locked up it indicates an ignition problem.

Dynos do not measure horsepower directly. they measure torque and speed, then calculate the horsepower based on the parameteres you give the processor. if you enter the wrong rear gear ratio on a chassis dyno the numbers will be all mixed up.
Any fault with the secondary vacuum diaphram is easily found and repaired. Much cheaper than a new carb.
There is a tiny cork "O ring" gasket that goes between the vacuum housing and carb body that may be dried out or missing.
To test the vacuum housing for seal remove it from the carb and compress the diaphram rod while plugging the vacuum signal hole with your finger. The diaphram should hold compressed until you release your finger from the hole. Not that hard to figure out.