Drivetrain Twin Screw
Hey Micheal! Randy Webb is the source of knowledge on this one. I haven't chatted with him on this in a few weeks, but there are some challenges in making this a viable option for us; the horrendous exchange rate, and the sourcing of the sc itself come-to-mind...
Meb, I think we've shared this link in the past, but for those that haven't seen it, here's a very good explanation of why a twin screw is superior to a roots-type s/c:
http://www.kennebell.net/techinfo/ge...romcatalog.pdf
I wish we could get a twin screw for a decent price, but it just doesn't appear our application represents enough volume to get economies of scale. Bummer.
http://www.kennebell.net/techinfo/ge...romcatalog.pdf
I wish we could get a twin screw for a decent price, but it just doesn't appear our application represents enough volume to get economies of scale. Bummer.
Hellooo Tony!
62Lincoln - yes we have.
I keep getting my stone busted by a friend who owns a Cigarette - boat - with an supercharged 8 litre V8 making something like 900hp. He waxes eloquent the obvious differences between the roots and screw type SC. I don't swim well so I don't pose much of a threat while over open water...just waiting to sneak up on him on the highway one day...teach him to make fun of my Mini...said I should be wearing a clown suit!
Do I correctly assume that a Wipple-charger is nothing more than a brand name for a twin screw?
Exchange rates...yuk! Very technical term BTW
Michael
62Lincoln - yes we have.
I keep getting my stone busted by a friend who owns a Cigarette - boat - with an supercharged 8 litre V8 making something like 900hp. He waxes eloquent the obvious differences between the roots and screw type SC. I don't swim well so I don't pose much of a threat while over open water...just waiting to sneak up on him on the highway one day...teach him to make fun of my Mini...said I should be wearing a clown suit!
Do I correctly assume that a Wipple-charger is nothing more than a brand name for a twin screw?
Exchange rates...yuk! Very technical term BTW
Michael
Why can't it be sourced from the US?
I really like the idea of the TWINZ but no one seams to be able to deliver.
What $$$ are we talking about if it had to come from Europe?
350whp is what I'm looking for and thats the ticket, well I believe, that would get me closer to my goal.
The twincharger would be too hot for our weather and the track. I like the turbo only idea but no one has one out yet at a reasonable price.
All in all I'm thinking of getting a 2nd car.. a *** since its very easy to mod and find parts at increadible prices (good parts).
Now look where I'm going
I really like the idea of the TWINZ but no one seams to be able to deliver.
What $$$ are we talking about if it had to come from Europe?
350whp is what I'm looking for and thats the ticket, well I believe, that would get me closer to my goal.
The twincharger would be too hot for our weather and the track. I like the turbo only idea but no one has one out yet at a reasonable price.
All in all I'm thinking of getting a 2nd car.. a *** since its very easy to mod and find parts at increadible prices (good parts).
Now look where I'm going
Trending Topics
Back from the dead!
Implementing a twin-screw supercharger is still the best solution, IMO. Rotrex has no low-end torque, turbos have crap drivability purity, and the roots blowers are way inefficient. Now, who will be the first to actually get a twin-screw bolted on?
Implementing a twin-screw supercharger is still the best solution, IMO. Rotrex has no low-end torque, turbos have crap drivability purity, and the roots blowers are way inefficient. Now, who will be the first to actually get a twin-screw bolted on?
PLEASE PLEASE PLEASE, find your way out to SoCal and take a spin in Longboard's Rotrex'd car....you will definitely change your view in regards to the Rotrex.
RMS had a kit available that used an opcon twinscrew SC
http://www.rms-tuning.com/cms/index....d=39&Itemid=58
Also Adam from minimania UK has been developing a kit ... I think it has been shelved due to economic climate (but if enough people showed interest he might get things going again).
http://www.minitorque.com/forum/f24/...rcharger-2136/
I'm not sure how many of those Opcon kits were fully developed. In theory they show promise but I haven't seen any performance data, nor have I looked very hard either. Right now the Rotrex and TVS show the most promise.
The Rotrex is pretty much finished, but still has a good deal of more power potential, and the TVS, if and when the 900 is released, will be an obvious choice. The efficiencies rival that of a turbo.
The Rotrex is pretty much finished, but still has a good deal of more power potential, and the TVS, if and when the 900 is released, will be an obvious choice. The efficiencies rival that of a turbo.
I have never seen the efficiency data for the Opcon, or performance data. Nor have I looked very hard.
As for production of the Rotrex, it's probably closer than anything else at this point. You'd have to talk with RMW to get the actual status, but I'd bet with enough people pushing they'd get made in a timely matter.
The twinscrew is nice...
but because it compresses at all RPMs besides just moving air (that's the source of it's high TEs), it takes a MORE WORK to twist it when at light load or low RPM. While the TEs are very good, I'm thinking the TVS will put a stake in the twinscrew heart. Here's why: THe twinscrew has very tight (much tighter than Eaton designs) so the manufacturing costs are higher. Couple that with the high licensing charges to make them to the holder of the IP, and you get a very high cost unit.
All told, the TVS design has much improved TEs, lower cost manufacturing, and the only thing that sucks is right now, it's only really done via OEMs who design the integrated cases, and I haven't seen the "bolt on aftermarket" versions like there are for the non-TVS Gen iV/V Eaton units. But anyway, as long as the licensing costs for the twin screw stay high, I'm thinking they've priced themselves out of the market, especially here in the states....
Matt
All told, the TVS design has much improved TEs, lower cost manufacturing, and the only thing that sucks is right now, it's only really done via OEMs who design the integrated cases, and I haven't seen the "bolt on aftermarket" versions like there are for the non-TVS Gen iV/V Eaton units. But anyway, as long as the licensing costs for the twin screw stay high, I'm thinking they've priced themselves out of the market, especially here in the states....
Matt
Before some tries out the twin-screw will get mad thinking of the best choice. 
I'm not quite sure. But I think there's a Greek guy who has a RMS Opcon kit fitted. Around 295-297 bhp.
Every now and then, I have a look at RMS price list and I think that's too much for a S/C. The whole kit price is mind-blowing! About 12k €, so around 17k bucks.
The Opcon S/C alone is around 5k€ so $7k. Still a lot!
Still I haven't made up me mind about what to do when I get 100k km or so. Yet, I still have time since me milage is 40k km in 2 and a 1/2 years.
I will keep researching, and see what I'll do.

I'm not quite sure. But I think there's a Greek guy who has a RMS Opcon kit fitted. Around 295-297 bhp.

Every now and then, I have a look at RMS price list and I think that's too much for a S/C. The whole kit price is mind-blowing! About 12k €, so around 17k bucks.

The Opcon S/C alone is around 5k€ so $7k. Still a lot!
Still I haven't made up me mind about what to do when I get 100k km or so. Yet, I still have time since me milage is 40k km in 2 and a 1/2 years.

I will keep researching, and see what I'll do.
Yes, but 297bhp is around low 260's at the wheels, if it has been quoted correct. And nowadays 260 is pretty standard fair on the M45 with the correct package. I would expect more considering the efficiency and dollars spent if the pricing is correct.
Leave you the link so you can have a look at it.
http://rms-tuning.com/pdf/VKMini.pdf
Every is in German so a translator will help.
http://rms-tuning.com/pdf/VKMini.pdf
Every is in German so a translator will help.
but because it compresses at all RPMs besides just moving air (that's the source of it's high TEs), it takes a MORE WORK to twist it when at light load or low RPM. While the TEs are very good, I'm thinking the TVS will put a stake in the twinscrew heart. Here's why: THe twinscrew has very tight (much tighter than Eaton designs) so the manufacturing costs are higher. Couple that with the high licensing charges to make them to the holder of the IP, and you get a very high cost unit.
All told, the TVS design has much improved TEs, lower cost manufacturing, and the only thing that sucks is right now, it's only really done via OEMs who design the integrated cases, and I haven't seen the "bolt on aftermarket" versions like there are for the non-TVS Gen iV/V Eaton units. But anyway, as long as the licensing costs for the twin screw stay high, I'm thinking they've priced themselves out of the market, especially here in the states....
Matt
All told, the TVS design has much improved TEs, lower cost manufacturing, and the only thing that sucks is right now, it's only really done via OEMs who design the integrated cases, and I haven't seen the "bolt on aftermarket" versions like there are for the non-TVS Gen iV/V Eaton units. But anyway, as long as the licensing costs for the twin screw stay high, I'm thinking they've priced themselves out of the market, especially here in the states....
Matt
The TVS will truly be the next big step for power hungry mini owners for sure




.