OPCON conversion

[MINIMANIAUK]

More road testing today -A fine sunny day so I took a run around Milton Keynes, came across a beautiful black DODGE Viper convertible LHD private plate ,anyone know the owner?nice car -couldnt resist - Think the MINI gained some major respect!!! , big thumbs up
Fuel economy with the Opcon is poor to say the least! with the increase in power if used ,there is also a good drop in fuel efficiency,with very very hard driving,returned 15.9 mpg
After a good workout for an hour or so the temps were great ,intercooler outlet was cold to the touch,and the inlet was barely warm,you could grab hold of it with your hand with ease(-I have taken the temp sensor off so cant give you an exact temp but way down on stock)
I will have to put back in the cat as the noise is far too loud with a performance exhaust,and manifold, Ok for the track but way too loud for road use.
The Tilton clutch is performing well,but I think the EXEDY is more suited to the road ,pulling away in first is awkward at normal rpms,thereafter fine and bites well. great on the track but not so traffic friendly
A

[Paul@1320]

Sounds good Adam, will we be seeing it Tue / Wed??

[Minipnut]

have an opcon/Eaton drag off ? ones that produce about the same Max bhp ? just to show the power of the baby =)

[MINIMANIAUK]

Tue/wed sounds good Paul.
If you drag 2 cars with similar hp ,with similar traction,and similar weight , you would get similar results!!!!!
The point of the conversion is to offer an alternative to the Eaton , which is a bolt on replacement so should your existing charger die you can replace / upgrade with the Opcon .
Or should someone be looking at raising the power output it could be fitted to a stock car as a stand alone replacement providing increased boost without the added heat of overdriving the eaton and using less crank bhp to spin it.
Having a lower output temperature (better efficiency) is the key as this allows more room to push the boost higher should more power be required (a simple pulley change)
Cost wise the bhp for buck would be similar once you go beyond the eaton pulley change,as to match the Opcon conversion on a stock car would require exhaust,manifold,pulley,plugs,head,cam ,air intake,intercooler, and the fitting set up costs, this would add up to a fair amount and still run higher temps and have torque drop off at the higher rpms. (look at eaton dynos above 6000)
The exhaust/manifold/heat etc can all be added to the opcon conversion and have the same benefits as the eaton for those that want more!!

[Ant FR]

seriously interested in this. Is that what the M7 Tuning cars are running as they sound really really whiny!

IS ths an exepnsive unit and does it require a remap to run

[Minipnut]

i thought i read somewhere though that the opcon charger produces quite a considerable amount more torque though ?

[MINIMANIAUK]

Sorry I don't know what M7 are using .
Torque and power are interlinked , the pulley size determines the boost pressure and what rpm the pressure is made at so it can be tailored to the powerband that you require,usually the max engine rpm dictates the pulley size,but the opcon can be worked a bit harder than the eaton so geared to have a higher boost at the higher rpms

[Paul@1320]

The M7 guys had a play with using an M62 without great success, Spider X is at the forefront regarding the M62 development and though I cant speak for him I believe he probably wouldn't go down that route again judging by his posts on NAM

[MINIMANIAUK]

The M62 is still a pump!!! just a bigger version with the same inherent problems,using a bigger hammer is fraught with problems by design.
Bigger is not always better, ask a V10 8 litre owner!!

[Damo]

Sorry but OPCON? I'm guessing this is a different type/make (both) of supercharger. Is this what Graham (of GRS fame) was talking about? Any chance of a bit more info for the less knowledgable of us.

[MINIMANIAUK]

The opcon supercharger is indeed a different type of supercharger,called a (twin)screw compressor.
The standard Eaton supercharger works like a pump ,air is moved from inlet to outlet of the charger ,but it only pumps a volume of air ,the air pressure inside the charger is the same at inlet and up to the out let.
After leaving the charger, air is pumped to the engine ,if the engine has more air pumped to it than it can suck you get a build up of pressure (boost pressure) The faster you spin the charger the more volume of air gets pumped more boost pressure ,
the screw compressor ,again pumps air from inlet to outlet however as the air is passed along inside the charger the area which contains the air gets smaller and smaller and smaller so the air is compressed as it passes through exiting the charger as boost pressure.(hence screw compressor)
this makes it more efficient and uses less power to turn,providing cooler output temperature at the same pressure ,
cooler air allows higner boost pressures to be used,and the opcon although smaller in size can provide more boost ,and greater volume of air at a lower temp all using less power to turn it!!

[chuntington101]

Quote: Originally Posted by MINIMANIAUK (original)

The opcon supercharger is indeed a different type of supercharger,called a (twin)screw compressor.
The standard Eaton supercharger works like a pump ,air is moved from inlet to outlet of the charger ,but it only pumps a volume of air ,the air pressure inside the charger is the same at inlet and up to the out let.
After leaving the charger, air is pumped to the engine ,if the engine has more air pumped to it than it can suck you get a build up of pressure (boost pressure) The faster you spin the charger the more volume of air gets pumped more boost pressure ,
the screw compressor ,again pumps air from inlet to outlet however as the air is passed along inside the charger the area which contains the air gets smaller and smaller and smaller so the air is compressed as it passes through exiting the charger as boost pressure.(hence screw compressor)
this makes it more efficient and uses less power to turn,providing cooler output temperature at the same pressure ,
cooler air allows higner boost pressures to be used,and the opcon although smaller in size can provide more boost ,and greater volume of air at a lower temp all using less power to turn it!!

sounds like a very intresting piece of kit!

what capacity is the superhcarger? would there be any way of incorperating a chargecooler core to the outlet of the SC (like the US V8 guys have) to help the intercooler out a bit?

thanks CHris.

[MINIMANIAUK]

Yes , an integrated charge cooler/intake can be done ,removing the top mounted cooler in total,and designed for maximum intake flow ,yes it will work ,yes it will show gains,but it would be expensive and few would buy it!!!
There have been a great number of things developed for the MINI which have been shelved as no one bought them!!
A larger Opcon can be used ,but as with turbos correct sizeing important ,the one I am using is good for 300bhp and more than adequate.

[Damo]

Quote: Originally Posted by MINIMANIAUK (original)

The opcon supercharger is indeed a different type of supercharger,called a (twin)screw compressor.
The standard Eaton supercharger works like a pump ,air is moved from inlet to outlet of the charger ,but it only pumps a volume of air ,the air pressure inside the charger is the same at inlet and up to the out let.
After leaving the charger, air is pumped to the engine ,if the engine has more air pumped to it than it can suck you get a build up of pressure (boost pressure) The faster you spin the charger the more volume of air gets pumped more boost pressure ,
the screw compressor ,again pumps air from inlet to outlet however as the air is passed along inside the charger the area which contains the air gets smaller and smaller and smaller so the air is compressed as it passes through exiting the charger as boost pressure.(hence screw compressor)
this makes it more efficient and uses less power to turn,providing cooler output temperature at the same pressure ,
cooler air allows higner boost pressures to be used,and the opcon although smaller in size can provide more boost ,and greater volume of air at a lower temp all using less power to turn it!!

Cheers for that informative answer.

Another question though if I may. If its so much better, why didn't BMW fit it instead of the Eaton? Just cost or other reasons possibly? Or is this one of those "we'll never know" kind of questions

[MINIMANIAUK]

purely a cost based decision the Eaton is a cheap alternative ,hence Jaguar,merc, also use them .if you add £1000 to the cost of each cooper s the manufacturer made it adds up to a lot of money.
They also cannot make their own version as the design is copyrighted and they would have to pay Mr Lysholm or his family royalties...