Re: [Chevelle-List] Carb and Headers

[Rob Thorburn]

I think the best advice on selecting a carb is to look at what GM did.  Depending on how hot your 396 is, look at the carb options offered on 396 engines, and match your engine (performance wise) to what GM offered on their 396 engines.  GM had 396 engines from mild to wild, so find one that is close, and select a similar carb.  Double-pumper Holleys are (more or less) racing carbs, the fuel circuits are quite rich, which matchs well with a big loping cam.  I like spread-bore Holleys for a daily driver.  You can get them in Double-pump and Vaccum secondaries.  The DP carbs are better with performance applications and stiff gearing, the Vaccum secondaries shine with those freeway flyer gears.  The Spread-bores also come in 650 CFM (small block flavor) and 800 CFM for the big blocks.  Spread-bores work well with stock cams and mild performance grinds.  They are Holleys replacement carb for the Quadra-Jet, and do produce more HP.  The down side is: the Q-jet gets the nod for smoothness and driveablity.  I put a Q-jet on my wife's '67 Malibu.  Note to self: It is important to keep the wife happy! Ha-ha  Here's how I would break it down:   Stock rebuild 325 HP 5000 RPM      750 Q-Jet (Vaccum) Stock rebuild 350 HP 5500 RPM     800 Spread bore (Double pump or Vaccum depending on gearing)                         375 HP 6000-6500     850 Double pump (wild street)                                       7000-8000+ 1050 Dominator (Drag racing)   I'm sure that will "ruffle some feathers", but I think that is correct,   Rob '67 Malibu '67 El Camino (in a basket)   ----- Original Message ----- From: Craig & Cerena Robertson To: [EMAIL PROTECTED] Sent: Tuesday, March 19, 2002 6:06 AM Subject: [Chevelle-List] Carb and Headers My intake has a 600 Holley Carb, which I'm told is going to be to small for my 396 engine.  The guy working on my engine suggested a 650 or 750 Double pumper or a 750 or 780 secondary Vac (I think that was the term he used).   Can anyone give me some pros and cons of each.  I am also going to install headers, any recommendations.  Thanks   Craig 69SS