Omega Piston CC
Turbo Mini Forums

the time has come to start ordering internals for the mini :)

been looking at +20" 10cc die-cast pistons as from what i have read and other TM members comments are sutable for the job.

looking at running no more than 16 psi boost, head still to have the chambers enlarged by Benross and unsure of the deck clearance yet as block is still to be machined so would a CR of 8:1 be acceptable.

using the AFRacing excel calculator this is where i am at the moment.

Bore 71.2 mm
Stroke 81.2 mm
Head Chamber Volume 26.00 cc
Compression Ratio 8.2:1
Gasket Volume 3.80 cc
Ring land Volume 0.5 cc
Deck Volume 5 cc
Swept Volume 323.30 cc
Total Chamber Volume 369.49 cc
Chamber - Piston Volume 35.30 cc
Chamber + Piston Volume 46.19 cc
Required Piston Volume 9.6 cc

the deck volume and chamber volume are the final CR factors but what are your thoughts

What the mind can conceive the mini can achieve
MITP 2012 17.01 seconds 1/4 mile against "The Don"
MITP 2013 16.83 seconds 1/4 mile

I had 10cc cast omegas and 28cc in the head and about 0.5mm deck hight 16psi no problem
If you garentee your self not to want more boost i personaly would run a little more compression maybe 8.5-8.7 probably make naf all differance tbh the final tune is where the benefits might be seen

Yes i moved to the darkside

Instagram @jdm_brett

there's always scope for more boost going to get block bored and piston's fitted to check deck height then go from there with what compression ratio i have with regards to boost level best also get onto mr Benross over machining chambers to 28 cc

What the mind can conceive the mini can achieve
MITP 2012 17.01 seconds 1/4 mile against "The Don"
MITP 2013 16.83 seconds 1/4 mile

We ran about 8.3:1 in the metro van with as much boost as we could throw at it on standard pistons.

8.16:1

If something is worth doing, it's worth doing half of.

Like I said, about 8.3

cheers guy's

so the general consenses is around 8.3:1

going to get steve to put 28cc in the chambers then check the deck clearance once the machining has been completed and that'll be the final CR

looking at a 0.020" deck clearance should have a CR of 8.3:1

Bore 71.2mm
Stroke 81.2mm
Head Chamber Volume 28.00cc
Compression Ratio 8.3 :1
Gasket Volume 3.80cc
Ring land Volume 0.5 cc
Deck Volume 2cc
Swept Volume 323.30cc
Total Chamber Volume 367.59cc
Chamber - Piston Volume 34.30cc
Chamber + Piston Volume 44.29cc
Required Piston Volume 9.99cc

On 30th Sep, 2013 John said:
8.16:1

What the mind can conceive the mini can achieve
MITP 2012 17.01 seconds 1/4 mile against "The Don"
MITP 2013 16.83 seconds 1/4 mile