4 replies to this topic

[Harry Beaver]

I'm after road driveability, not outright power, therefore torque is the most important thing.

To run with an SW5i-07, LCB RC40, K&N element

[Sprocket]

Moved

[Sprocket]

I'd say that its best to get a head that is meant for the injection engines, that means that the locating rings are still used to locate the inlet manifold correctly. Steer clear of tunnel port full race heads. Something with 29 and 36mm valves is a good bet. As far as im concerned its all in the porting of the head on injection engines rather than trying to fit the biggest valves you can. As a general rule these heads are usualy labled stage three and stage four. Varying prices from the likely tuners.

Dev, over to you

[Dev]

traditionally tuners tend to use so called stage three heads for the best all round performance as this both gives a good power return and economy. personally i have found stages can differ with each manufacture or tuner.

I have a minisport stage 4 on mine and i must say i'm very happy with it the port work is outstanding and it provides a great deal of torque. although i was somewhat disappointed at last weekends RR power shoot out thingy, i think this is down to a few minor technical issues and nothing a good service and clean out wont sort. FTR i made 80 with 81 lb/ft torque, which is down by at least twelve on both and have noticed that the clutch is slipping too. but moving on.

As for using the head with a non standard cam, i would definately reccommend the swiftune sw5i. In fact unless you are getting Bill Richards to custom profile you one i would NOT go anywhere else. Swift tune are the best with out a doubt. With this cam i would expect you to find that your "cam band" to raise slightly, mine is 3k to 6.7k hard cut.

To be honest with you the best and most effective modification you can do to optimise performance on your MPI is to change the diff. The 2.7 is far to long for the power associated with a N/A set up. I reccommend with 3.1 or 3.44. The 3.44 being the prefered option due to the power being there all the time due to its length. You do lose your top end cruise but how often do you want to sit at 90 in a mini. Country roads is where its at.

Sorry to waffle, and i hope this helps.

Cheers
Dev

[CooperTrooper]

always a help Dev im getting my stage 4 head on monday