[RLS67SS396]

I have a matching numbers 67 SS 396/350 with a factory Holley on it. I have been to many shows and cruizes since I bought this car about a year ago but have not seen many 350 HP matching #'s cars and I have yet to see any with my set-up on it... which is I believe, a factory Holley 585 carb (List 3837), with automatic choke, sitting on top of a cast iron Holley intake manifold. I have heard and may have even read somewhere that most 67's w/350HP motors had the Rochester set-up. Is this true??? Is this a rare "factory option"?? or are there just so few "untampered" '67 cars that this is the only thing that may make this set-up a little scarce?
My carb probably needs rebuilding which is not my cup of tea if you know what I mean. Do you recommend sending it back to the factory to be set to original specifications or does anybody know a good shop that knows the tricks to make this carb perform better than the factory expected it to? Can this carb be purchased new anywhere?

Also, as long as I am on the topic of this carb, maybe keeping the carb stock is not what I need anyway. Recently I put a set of Dynamax 2.5" headers with 3" exhaust into Magnaflow mufflers with 2.5" out the tail pipe. My main goal for this set-up was improveed sound... and this is what I got. Many people said I might lose some HP by doing this but that wasn't much of a concern because I don't race the car (use just for a cruizer). But since I made this change, the car seems to be starving for gas on the top end now. This happens right before I shift into 4th gear and through 4th, when I have my foot into it. (Note: I said I don't race it, but I do like to have fun with it once in a while). When I have the carb rebuilt should I replace jets with larger ones??? Any suggestions about what size I should use?? Or, is there a direct replacement carb that would use my existing choke and manifold set-up (don't want to remove the stock appearance if I don't have to)??

Lots of question above I know. Any responses and help would be appreciated. Thanks in advance.



[This message has been edited by RLS67SS396 (edited 08-31-99).]

 

[67RAT]

rls67ss396
I would go bigger jets on the secondary side,maybe 2 #s,if the top end still lacks go 4 over what you have now.see how it likes it.maybe go 1 or 2 #s up on the primary side.you now made the out door bigger,exaust.so now the in door must be made bigger,more fuel. hope this helps 67rat member #199
probably seems to nose-over,this should help.

[This message has been edited by 67RAT (edited 08-31-99).]

 

[Harvey]

I have the same set up. All 1967 350 HP cars came with the holley carb #3908958 and cast manifold cast #3866948. In 1968 Chevy went to the QuadraJet carb on the 350HP.
Harvey

 

[Tom Mobley]

RLS, sounds to me like you might have a fuel delivery problem here, probably just became more noticeable when you opened up the exhaust. Check the basics, fuel filter, lines, pump, rig a temporary fuel pressure at the carb to see if it's running out of pressure on the big end, all that. Those carbs had a sintered bronze filter thingie behind the fitting where the fuel line enters the carb, this is often overlooked when changing fuel filters. They get plugged up real bad over time. a fuel pressure gauge hooked up anywhere in the system shows great pressure but the carb runs low on gas anyway. Drive ya nuts if you don't know about it.

Tom

[This message has been edited by Tom Mobley (edited 08-31-99).]

 

[RLS67SS396]

Thanks for the help guys !!!