|
THE TORO IMPELLER SUDDENLY THE GATOR SUPERCHARGER TAKES A NEW TURN… The large impeller we've needed so long has suddenly appeared. It's 4 3/4in. and two sided as you see here. Two impellers for the price of one-just $28.00 plus shipping and readily available from numerous retail stores and Internet parts suppliers. This changes everything as the Gator belt drive turbo suddenly becomes a real supercharger capable of much higher boosts and providing for larger inline and V-6s. The details are carried in detail in our current (No.156) and upcoming newsletters. (check the "books" page of this website for information on our "Supercharging Small Engines" book and by monthly newsletters)
A. 4 3/4in. impeller in a supercharger destined for small 6s, 4s and 2/3 cylinder recreational engines? Some would climb this is madness as modern blower technologies seems to dictate ever smaller impellers and ever higher impeller speeds, yet the principle of using larger empowers in relation to engine size is as old as superchargers themselves. Using duel impellers on one shaft dates back to 1927 (at least) when Dr. Sanford Moss built one for an Indy car. His dual impeller supercharger produced "over 40 psi" at a mere 26,500 impeller speed on a 91 cid Miller engine. Estimated power was 300 hp, nearly double that of other Indianapolis race cars of the day. (Design & Development of the Indy Car, H.P. Books) Moving forward to the March-April, 1973 issue of No.3 of my Total Performance Studebaker newsletter, you would see a photo on the cover of John Erb's new Paxton Competition impeller (top right-below it, a stock Paxton impeller). Turning to my comments on the inside front cover: "Erb's new impeller would allow anyone to produce approximately twice the booster of the R-5 (the duel supercharged Stude that ran at Bonneville in 1963) using just one Paxton supercharger". John's impeller uses 16 vanes, the Paxton 10. Notice how large the vane's are on John's impeller.
Dual supercharged Studebaker V-8s Are not that uncommon and Ted Harbit's, Jim Lange's, and Tom Covington's are featured in my books. All produced 12 plus psi boosts-twice that of one Paxton at the same impeller speed. Few realize that Paxton offered a two Paxton setup for 5 liter Ford V-8s in the early 90's and advertised it in various high performance magazines. Here's a Paxton ad from the December in 1992 issue of Car Craft with photo and caption: TWIN CHARGERS Could you use 647 horsepower? It's not yet CARB-approved, but Paxton is working on it with its twin supercharged 5.0L Ford as the first of the Granatelli Signature Series.
Conclusion: Large impeller size in relation to engine size can make double digit boosts at moderate impeller speeds. Below: Jim Lange's old duel Paxton setup used fuel injection. Both engines could produce 14-15 pounds boost and plenty of power
but under hard use the Paxtons were short lived. Turbochargers can produce
20 plus pounds of boost and be reliable for long periods at that level
in race car applications. For more normal streetcar use, Paxtons are
fine.
|
 |
 |
 |
 |
