Quadrajet Problem Solving > Dialing in your rebuilt Quadrajet carburetor

Secondary opening too soon or late?

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68rs/ss:
Idle quality is good. Fairly smooth. Vacuum is up from the original extreme energy Comp cam of 11in/vac to 15in/vac at 750RPM with the Speed Pro CS-179R cam you had recommended. Easier to tune to highest vacuum and does not stink out the pipes.
 I did put it on a chassis dyno a couple of years ago. Just the way I drove it in, it put out a nice flat torque curve in the mid range. Peak torque was 324 and HP was 292 @ 5200 rpm. It showed a little lean on the upper end, but have since increased the fuel pressure to 6ish from the tested 4.5lbs.
I know the numbers are not staggering, but remember, that was at the wheels. I've been told you can add 20-25% to get a flywheel number, which would put it around 350-360HP and 380-390 ft/lbs of torque.

I have since added 1.6 rockers and changed the mufflers. The unknow make of mufflers that was on the car were 2.5" inlet/outlet. But looking down the inlet, the pipe was expanded from 1 7/8" to the 2.5". The replacements were  true 2.5" all the way through. It feels like it picked up some, but have yet to go back for another dyno run. Hopefully it gained with those changes. Some timing adjusts might help too.

This is a street car and works very nice.
Thanks

Cliff Ruggles:
I've never been the least bit impressed with any of the Comp XE camshafts.  They show some "bling" at idle, stinky exhaust but come up short beyond that.

The chassis dyno numbers look good, and the addition of 1.6 rockers will make even more power......Cliff

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