OPCON conversion

[MINIMANIAUK]

Various combinations are now being tested,throttle size, (now 70mm ) pulley size ,(now smaller), various bypass valve arrangements, injector sizes. -each alteration gives important information on boost levels /temps ,throttle response,belt lengths,fuelling .
Each pulley size alteration causes a change in boost pressure ,and until you run that size pulley the boost level is unknown ,
The pulley is bolt on so an easy job to replace,no puller is required ,it can be done with engine in its mounts ,not needing lifting,just 1 bolt and tighten to 30ftlb , and a new belt .
Back on Dyno next week ,and see what the output is raised to .

[MINI-Morgan]

Sounds good Keep us updated with how the Dyno goes next week

Certainly seems there is a massive amount of different in the power required to drive this supercharger compared to the Eaten. Producing 16Psi would be nice

[Loui]

Quote: Originally Posted by MINIMANIAUK (original)

Various combinations are now being tested,throttle size, (now 70mm ) pulley size ,(now smaller), various bypass valve arrangements, injector sizes. -each alteration gives important information on boost levels /temps ,throttle response,belt lengths,fuelling .
Each pulley size alteration causes a change in boost pressure ,and until you run that size pulley the boost level is unknown ,
The pulley is bolt on so an easy job to replace,no puller is required ,it can be done with engine in its mounts ,not needing lifting,just 1 bolt and tighten to 30ftlb , and a new belt .
Back on Dyno next week ,and see what the output is raised to .

Good luck with it Adam im sure it will make good power

[Bhozar]

I wont be at the BMW show, so will miss you running on the strip. You still going to the MINI Action Day at Combe? Would be good to see it run around the track.

[roland2003]

Hi Adam, did you ever try fitting the vacuum guage before the TB but after the filter ?( Clean side of the air filter) to see if the filter was restricting (stretching the air) rather than the TB. What size filter are you using? Hope you can make it on the track at the Castle Combe Mini action day on Sat 29th Sept.

[chuntington101]

Quote: Originally Posted by roland2003 (original)

Hi Adam, did you ever try fitting the vacuum guage before the TB but after the filter ?( Clean side of the air filter) to see if the filter was restricting (stretching the air) rather than the TB. What size filter are you using? Hope you can make it on the track at the Castle Combe Mini action day on Sat 29th Sept.

a great idea!!! could also try and fit one after the TB and see if the TB is big enough??

Chris.

[Revolution Mini Works]

any word on the Opcon?

[Paul@1320]

Looks like you've got to make more than 250whp at 7k Adam otherwise you wont here the last off it.

[MINIMANIAUK]

Only 250whp - no worries , no funky gearbox on the charger ,or silly high rpms too

[GTT 280]

will we ever see the opcon merge into the GTT kits?

The GTT kit i already have fitted to my car is top grade workmanship. It more than meets my needs....... but woldn't it be nice to add just that little extra refinement?... )

I'm sure i asked this before Roland, and i think we both agreed its more than just a bolt on activity.

Cheers,
K.

[Revolution Mini Works]

Quote: Originally Posted by MINIMANIAUK (original)

Only 250whp - no worries , no funky gearbox on the charger ,or silly high rpms too

250whp was only at 7k..... not to mention it WASN'T even tuned..........

funky gearbox? HUH???????????????

[Revolution Mini Works]

Quote: Originally Posted by 1320autos (original)

Looks like you've got to make more than 250whp at 7k Adam otherwise you wont here the last off it.

Bueller?

[Penguinracer]

Adam, is your conversion using the standard head? There seems to be a great deal of misinformation about the limitations of the standard head. Can your conversion deliver 260 - 275 bhp (flywheel) with the standard head? It is often said, correctly or incorrectly, that about 240 bhp is the limit with the standard head using the Eaton. Your more efficient charger may be producing lower intake temperatures & thereby delivering greater power with the standard head through greater intake density. My question is this: With a pullied Eaton blower (15%, 17% or 19%) which is the weaker link in generating more power - the charger's inability to deliver enough air or the head's ability to ingest & exhaust the mixture? I often felt that a pullied Eaton runs out of puff (& loses thermal efficiency) well before the standard head hits its limits?

[MINIMANIAUK]

the gains with the conversion are around 20+ by using less power to drive,and 20+ by having cooler more dense air at the same boost levels, these gains increase as the boost level is increased ,and charger rpm increased,. -so a 220 eaton conversion would see 260 with opcon at the same boost.
if stock head limit is circa 240 then 280 would be the opcon equivalent.
head and eaton charger work against each other ie the heads flow restriction ,causes the boost pressure to be higher and thus causing the eaton to enter a far less efficient area when pullied.
The eaton does not like going much over 13 psi , it will do it ,but starts to lose efficiency,the stock head adds 2-3 psi by restriction,this varies through the rpm range ,at the lower rpms ,cam,valves, dictate the airflow,at the higher rpms the exhaust valves and manifold dictate the airflow.

[MINIMANIAUK]

UPDATE
After many hours trying various combinations,I have now fitted a revised intake to the charger and a smaller pulley ,also removed the extra injectors and moved to 450cc to replace the stock ones.
the intake size and length make a large change to the operation of the charger and move both boost output and rpm that the boost comes in at ,torque seems to have increased a lot and moved slightly higher up the rev range.
Reliability has not been a problem the charger has worked faultlessly,so early in the new year its back to the dyno to get some more numbers.
I feel the present set up is about right for a road use car ,plenty of power and nice and linear,
Not having the extra injectors/control unit also will reduce costs
Tried very large throttle -far too snappy and throws up too many EML issues (race use only -and would need a standalone ECU )
Could a smaller pulley be fitted? -yes but I feel the extra torque would be unnecessary its already at the traction limit and any more would become a handfull to drive and need a revised traction control system.
I will try to get some in gear accelleration times as soon as the roads dry out -I cant get grip at the moment
As the current superchargers clock up higher mileage and start to fail,this would be a reasonable alternative for an upgrade as a bolt on kit especially if I can reduce prices further still