Barry Grant Speed Demon

[StanJ]

Ooops...I didn't even think about looking to see how old this thread was before posting to it...and actually, I committed another gaff by posting as I did in Pat's thread...considering that I'm technically in competition with him, business-wise. My apologies Pat; I dropped the "professional courtesy" ball here.

Now to Steve's comments...

Actually, I mentioned decreasing the cross-sectional area of some passages (main wells in particular) in the metering block as an example of a modification that is sometimes necessary in order to tailor the fuel conditioning/delivery curve as perfectly as possible for some applications; I didn't mean it as a wholesale damning of the Demon metering block design; they work quite well for a broad range of applications. The point here is that while most of us in the performance carburetor preperation industry have had access to raw, unmachined metering block, venturi body, and baseplate castings from Holley for several years, Barry has elected not to sell such "unfinished" components for the Demon line. So, something like changing the emulsion area/cross-section gradient the right way (I won't bore everyone with the long-hair physics involved, but there's a lot more to this than just air corrector and emulsion orifice sizes) in a Demon requires quite a bit of fabrication and machining.

Regarding boosters, BG does have several different designs available for the Demon, but what if your particular application requires something outside the norm...say, 358 cu. in., professionally ported heads and manifold, 12.5 to 1 compression, any camshaft profile and practically any carburetor modifications...just so long as the venturi diameter doesn't exceed 1.252" and the throttle bore diameter doesn't exceed 1.562"? (Grand American Challange guys know all about this) If you're running a Ford (and hey, if you're not...what are you doing here?), then any of the Demon booster offerings from BG are going to have a performance compromise somewhere in the RPM range; their signal curves for the range of venturi air speed this application presents are simply outside the parameters of what this engine will want and there is no real way to "tune" out of the problem (and heaven help you -- and your pistons -- should you decide to get creative with oxygenated fuel).

Actually, the same holds true with any "stock" Holley booster in this application, but at least with the Holley 45R-312 "severe duty" booster, you have a workable starting point to get where you need to go airflow and signal-response wise, and just as importantly, we have access to them at a reasonable price. Barry will never tool up to cast Demon boosters of the design that I use for such an application simply because he could never sell enough of them to recover his investment, much less make a resonable profit. This type of thing best falls to people like Pat...or me.