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Thumpr Junk

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Kevinb1:
I've spoken with Cliff several times on the phone and hes been a great help trying to tune my 327 that has a Mutha Thumpr cam in it. I'm at my wits end trying to tune this engine using this cam shaft .
I'm running 30 degrees initial timing and I can't stay in the garage while I'm trying to set the fuel mixture because of the gas smell coming from the exhaust.
 I've decided to remove the cam and go with something else, just not sure what.
I'd like a nice sound at idle, but lots of torque on the low end. I don't plan on driving the car on the interstate much, mostly just round the town or country roads at 60-65 MPH. I'd like to keep the stock look, so no headers or after market heads at this time.
Car/Engine Specs
1968 Camaro Conv
4-speed
3.08 12 bolt rear end (will be changed to 3.42 or 3.55)
327-10.0:1 compression (1972 Chiltons Manual)
.30 flat top pistons,
stock crank
original "double hump" 1.94/1.5 heads with Z28 springs
Mutha Thumper CAM .489/.476 lift, .235/.249 @ .050" Lift
Stock points distributor with an MSD Blaster 2 coil
Quadrajet #7028212 DH Built to the third recipe in Cliffs book.

Any advice or opinions will be greatly appreciated.

77cruiser:
Pretty hard to have a clean smelling idle with a big cam, but if you went with something about 10 -15 deg. less duration it would idle a lot better.

Cliff Ruggles:
Look at what cam the factory used for the 327/350hp engines and those engines had more compression.

222/222 @ .050" on a 114LSA.

The cam you are using just has too much duration and LSA is way too tight for the CID and compression ratio.

I get more complaints to the shop from folks who have chosen Comp XE cams on 110LSA's and the Thumper cams on 107LSA's than any other.

If it were my engine I would install the Speed Pro CS-179R cam instead.  It's a direct replacement for the 327/350HP camshaft, and will idle better and make more power everywhere compared to the current camshaft......Cliff

Kevinb1:
Thanks for the response.
Cliff
I just rebuilt the quadrajet using a rebuild kit and book that I got from you. I also built it to the the third recipe in your book which was designed for large cams.
Will I need to order another rebuild kit and set the carb up for recipe#1, or #2?
Or will I just need to find another quadrajet and start from scratch?

novadude:
It's not the LSA that is the killer.  It's the overlap that comes from tight LSA and excessive duration. 

I have a Q-jet that is built to (approximately) "Stage 1" recipe specs on a 9.6:1 355 ci running a 217/225 @ 0.050" hydraulic roller on a 108 LSA, and it idles great at 800 rpm, runs high 12s @ 108 mph, and gets very good highway MPG (~19-20 MPG with 3.36 gears and no overdrive).

Don't be afraid of the tight LSA cams - just choose duration appropriate for the combination.  David Vizard gives great SBC cam advice in his books.  I followed his "recipe" and I couldn't be happier.

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