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Author Topic:   Holley 500cfm or Quadrajet??????
#28
Member
posted March 12, 2003 10:47 PM
A lot depends on what intake, heads, etc can be run underneath the 4412, but a well-built quad will ALWAYS flow more than the 4412's.
BUT, so much more has to be done to a quadrajet to make it usable for racing, whereas, a 4412 is much easier to tune, adjust and dial in for each application.

Quads will typically be a bit more costly than a 4412 to get done right, too.

It's like the old saying, "6 of one, half dozen of the other..."

Both setups can be made to be fast, tho, it's just a matter of building the entire motor specifically for that situation, or around the fact that you'll have a quad on it, or a 4412...

Hope that helps,
KPLugnut


#28
Member
posted March 14, 2003 10:09 AM
Ummmm...how many ya want? LOL....new or used are in stock....

KPLugnut (aka Dayton Umholtz), owner
Kinetic Performance http://www.kineticperformance.net


#28
Member
posted March 14, 2003 03:45 PM
28.. with the motor rules as they are in SIMS/ULMA a 4412 will flow enough for all the rpm's you want.I ran one all last year and love the way it performed., actually turned 7200 one night by accident when a axle gear stripped. The throttle response is great off the corner, It doesn't have the famous stumble off the corner like a Quadra-junk (LOL) I think you will be pleased with a 4412.


RC Racing
Member
posted March 15, 2003 04:45 PM
KP, I've heard the "stumble out of the blocks" trait attributed to quadrajet before. Do you have comments (reason, fixes, etc.)

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KPLugnut
Member
posted March 15, 2003 05:48 PM
several things contribute to that, and in a nutshell, it's because the quadrajet was not designed as a racing carburetor.
Rear air flap tension, emulsion tube work, altered metering rod/cam combos and about half a dozen other things are "fixes".

Based on the feedback from our customers, our quads don't seem to have that problem at all. At least not once the user gets a handle on fine tuning the rear air flap spring.

Hope that helps,
KPLugnut


ryan
Member
posted March 15, 2003 10:30 PM
Dad does my tweaking on my q-jet and I haven't once had carb trouble on the track. Knock on wood.


DEEDDUDE
Member
posted March 16, 2003 09:53 AM
RC if you need some Q-Jet work let me know. I'm not a carb. guy, but I rebuilt (tweaked) mine and it doesn't stumble. Plenty crisp. It's all "stock". It's running up against some of those high dollar carbs. But if you want someone who knows what their doing have KP look at it. I think that the secondary tension spring adjustment is probably the most important in fixing the stumble.


o5racer
Member
posted March 16, 2003 11:18 PM
Hey KP. How much would a replacement metering block run for my 4412? The main body was very very warped when i got it. got that milled and it runs great for about 6 nights. after that it starts to peter off. If I just tear it apart and put a new metering block gasket in it its fine. I think the block is warped and will only seal when the gasket it new. after it starts to shrink a little it doesent seal.


KPLugnut
Member
posted March 17, 2003 09:49 AM
I have good used ones for maybe $20, but a new stock one would run $60 bare, or $75 all assembled with P/V, vent baffle and gaskets.
A fully modified HP series one with all possible machine work in it will run $100.
All prices don't include shipping, of course.
Just choose which flavor ya want and I'll send it out ASAP.

Thanks for askin'.
KPLugnut

p.s. - And if you're still having troubles, there might be other things going on with your carb, such as a slowly sinking float.



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