Author Topic: newbie seeking advice  (Read 2451 times)

Offline murph3204

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newbie seeking advice
« on: October 10, 2010, 07:34:48 PM »
Hello all, I would appreciate any advice or direction about a carb for my drive train.

I have a 69 Pontiac 400 #16 heads, stock intake, .030, that was rebuilt in 1998 by a shop that used a basic engine rebuild kit with dished pistons.  Its been a while but i think i remember the shop saying that the compression would now be around 8.5:1?, dunno.  Anyway, the intent was to replace the tired stock 2 bbl 350/ TH400 in my LeMans convertible.  The engine sat bagged in my garage until 2004 at which time the upper valve train was replaced with roller rockers and an XE262h cam was installed. (stock 400 exhaust manifolds), it was bagged and has been sitting in the garage, never fired, waiting to be installed.  This time though I plan to convert the car to a 4 speed and replace the differential with a posi.  (currently an open 2.78:1)? The 4 speed i have now is a fresh M21 but will probably swap it out with an M20 at some point in the future. I don't have plans to race the car but I do want it to have a little pep while I row through the gears around town.  Mileage isn't too much of a concern as it won't be a daily driver. My question is which carb would be best to use with this setup and with what ratio in the rear?  

I currently have two quadrajets on hand; a 07044513  which is in considerably better condition than  the other one, a 7042251 which was rebuilt by a friend who couldn't get it to run right so he gave it to me.  I'm not attached to either one and would consider using a better choice based on recommendations from this forum.

thanks in advance.

P.S. I have ordered the carb book.


Offline Cliff Ruggles

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Re: newbie seeking advice
« Reply #1 on: October 19, 2010, 03:48:15 AM »
The 7044513 carb is a nice unit, side inlet Chevy carb.  It's a divorced choke model,  the Old's is a hot-air style choke model.

Either one could be set up to work effectively for the application.  The book has all the information to do this, we sell the correct parts to get it done. 

The Old's carb can be easily converted to an electric choke, which may have an advantage in your particular applicaton?.....Cliff

Offline murph3204

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Re: newbie seeking advice
« Reply #2 on: November 23, 2010, 10:16:02 PM »
starting to tear into the 7042251 and so far doesn't look too bad.  I'm thinking of using recipe#1 for the build back, would you agree?

Offline Cliff Ruggles

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Re: newbie seeking advice
« Reply #3 on: November 27, 2010, 04:17:59 AM »
I'd use recipe #2, due to the low compression ratio and 110LSA camshaft.....Cliff