Discussion in 'General Auto Conversion Discussion' started by Doggzilla, Sep 14, 2019.
OK. Just wasn't sure if it would handle 700 shp at 8700 rpm
They handle thousands of HP turning a blower.. they can handle 700 hp especially when it’s low torque, 422 ft/lbs
OK that sounds promising
So who's doing the analysis so we can start building?
Insane 4am thoughts with a teething kiddo waking me up early... Since you'd have a hollow shaft running right between the heads - could you leave the point of the spinner open and use it to 'duct' cooling air straight to the heads?
what Engine are you planning upon using?
NW Aero Performance and Belted Air Drives both used the Blanton design with their V8 packages. THere has also been some one off copies of the Blanton design. They've been running since the 80's. They are/ need to be very sturdy, which translates to a bit heavy. If they are not adjusted/tensioned properly, the belt will move toward one edge and shred itself. Mine uses a 12248M12k which around 4.5" wide. There are several companies that make the belts. The belts should be replace every 2 years or sooner if they show wear. They have plenty of strength.
Mazda Rotary 20B
is the Blanton Design a similar belt to the Gilmer Belts?
Gates and Goodyear have a wide assortment of sizes. The strength comes in from a combination of width and the pitch of the teeth. The larger the pitch the stronger the belts are.
Do you mean they are used to spin the blower on thousand horsepower engines, using a couple of hundred hp max?
If not, please provide a link to the "thousands of hp" belt drive.
About 1,000 HP delivered into the blower by the belt drive, about 10,000 HP out of the engine.
TBO of 5 seconds at power.
Actually the blower consumes about 2-3,000 hp. The net is greater with the blower but it takes power to make power.
OK I've just realised that you are referring to a supercharger not a snow blower!
Exactly. I’ll dig up a photo of how we did it in the boat and see if I can post it.
Yeah but the motor was always under-powered (40hp) and when Hirth had a suitable 70hp motor they went bankrupt and most of those engines never got delivered.
That was my meaning. Where there TV issues as well? Yes. But ASIDE from that the motors simply never performed, or were never delivered.
And I agree that this is almost always the 'E'xperimental part of E/AB rearing its head. Lots of early failures in design, not the underlying concept.
Yes. Gilmer Belts had trapezoidal teeth, The belt I have has round teeth.
As for the drive shaft I think you could get a bigger head start using a motor that already has a countershaft in the design (many 90deg engines need a countershaft to help reduce vibrations).
This means that the block is already drilled for oil passages and the block ends already have a thick hunk of metal line bored for a sizable shaft.
Auto engines are not about weight savings. You really can't save that much weight. Auto engines are about saving money on the initial purchase and maintenance (and rebuild).
I'll happily give up 100lbs for a motor I can actually afford to run and maintain.
Gates Powergrip HTD belts (the latest versions) have round teeth in round sprocket grooves. Supposed to run cooler, and quieter and transmits more torque as the failure is to shear the base of the tooth off which is much larger than trapezoidal. I have seen a trend toward these belts in timing belts.
Don't ever say airplane around anyone from Gates or any of their suppliers. Say garden tractor.
Used them on pretty high horsepower blower test rigs. They are stout! If you run them well below spec and cool them well they have quite good life.
GT series are the successors to HTD with GT carbon being the highest power rated yet. More power and life, less noise.
Designing a belt reduction for X hp is the easy part. Download the catalogue from your favourite belt manufacturer and go through the sizing process. They have tables for hp per mm of width for various pulley sizes.
Designing a redrive that does not have TV issues is much harder. That is not even hinted at in the catalogues.
Separate names with a comma.