Wondering if someone would explain the concept behind the Rotofaze blower manifold. Each runner looks to have a port for individual tuning. Is this the case? If so how does one tune? I'm a bike guy but have stopped by here off and on for years for cool tech a period rides. Thanks.
It only works if the blower rotors are straight and not twisted. Twisted rotors throw the mixture to the front and would not get to the back runners. Most Big show fuel teams set the blowers back to the center of the manifold. It was a nice piece but totally lacked engineering
Just looks like an individual runner, cross ram design, without much of, or have any plenum. Notice the separate pop-off valves in each port, hence the individual runner design..! Other pictures show it with the runners crossing over side to side. I'm not sure I'd run it as designed, but adding a plate of some thickness (1.0" or 2.0" thk.) to connect all of the runners might make it a usable manifold for someone's hot rod. As for the "twisted" rotor and moving it back... Plenty of guys ran a full open case, twisted rotor for MANY years with few ill effects. And...to PROPERLY...move the blower back, it needs to be either a modern case, or an adapter plate with the smaller, front opening to allow ONLY front exhaust of the air into the manifold, not a full open design blower case. This manifold would not work with a modern, small opening case blower. Mike
Bob Ida has one on his blown 'Hemi Healy' - was what he ran back in the 60's, so when he restored his old race car - he ordered a manifold from Joe and put one back on the car. Here is a video I took when we were out having some fun at the "Ohio Mile" . . . good times and a great dude . . .
anything can work- its how well they work and will the racer bennifit from it. The little Healy is the only car Ive seen with it on and running, IDK- could have machined the "ICE CUBE" tray out of it to give it a little plenum. Even with and open bottom of the blower case the air and fuel moves forward the more you spin the rotors. The reference to the modern racers was to imply that it still does, and the goal is to get even air distribution into the cylinders. The short run from the back of the blower trying to feed cyln's 8-7-5 with pressure was weak. But whatever, no other manifold has ever designed this way since, they all connect the runners to a plenum
Modern competition blowers have bottom case openings like the above - this is a Fowler/Kobelco HurricaneForce/F12 lower case opening (I helped them with design, marketing and patent work). The blowers are then set-back quite a bit - to attempt to get even pressure distribution to the cylinders. Also, having "down nozzles" in each port is critical as it gives the tuner a way to alter the amount of fuel that each cylinder gets. Anybody who races alcohol or nitro will keep exact records of the various nozzle sizes needed (cylinder by cylinder) to achieve the right temperatures and mixtures. You'll never get even fuel distribution without down nozzles . . . just the way it is. The 'Isoport' manifold from Roto-Faze would surely benefit from having a plenum above the ports and I would probably run down-nozzles even on gas. (Obviously I'm talking about MFI - though the same concept applies to EFI conversions - you don't put all the fuel through the hat.)
Just for fun (and I realize this is off topic - my apologies) - here is a rendering of the complete Fowler 14-71 HurricaneForce billet blower (innovative clamshell design) with the new carbon injector hat on it. I did this from the original SolidWorks models - applied all the textures, colors, materials, etc.. It came out better than the damn photo work we did! LOL
I remember Joe Panek’s manifold on a FED but the name of the car escapes me, and for sure Marcellus & Borsch had one on the F/A for a while, but really, it is a 50+ year old design that was unsuccessful, so what? Loads of things were tried over the years, some good and some complete duds but they are all a part of performance history. How about Ivo’s four engine car? Never ran to it’s perceived potential but we admire it to this day. Even I do, long after seeing Norm Day’s crew “wiping” the stones and dirt off the slicks before a run. Those oil soaked rags helped the show and as they say- “And the crowd went wild!”
Truth for me is that I like the LOOK of the Isoport manifold . . . as I'm not currently running one and not racing with one, would still like to have one on an ole' 92!
https://www.facebook.com/video.php?v=2215951402048900 This was engineered -programed-machined by Tom Shelar and with input from many big show Crew Chiefs and used by a lot of the major players. Tom is also a very good customer as I do all the repair on his Nos T/F dragster that just set the ET and Speed record @5.49 and 265mph ,a 417 Donovan "6-71" and a 2 piece center dump manifold. Ivo's car was never meant to be a serious racecar, after he ran the twin, he thought about the quad. as soon as the nitro ban was lifted, he sold the car and went fuel racing
Joe showed me a pic of the "WING" with the ISO-PORT, all the back-fire ports were open/popped with flame coming out. The argument over my workbench was Joe was upset that they would not allow his manifold to run in NHRA nostalgia Competition ? Joe!!! it has no place for a SFI burst panel-- Those are the rules!!! But-tttt all the poppets are open with flame coming out of them, And that pic was from many years ago when we did not know how to run the volume of fuel we run now
(Obviously I'm talking about MFI - though the same concept applies to EFI conversions - you don't put all the fuel through the hat.) You still have to put fuel through the hat to keep the rotors wet. Increasing nozzle size at the back of the hat does not increase fuel volume to the rear cyl's, it's just more volume overall. Now, if it didn't take so much HP to turn that 14/71 ,and if the bottom opening was matched to the I-P opening, then the manifold would work because there was enough rotor length behind the back runners to deliver air. Also throw in a 7-4 cam swap
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