IM….. OHLA
MK 3.6578 AND A BIT MORE WHICH IS IT?
Whats this then?
A mk one, two, four or version x. y, z or 10.223 plus or minus one point 2 and half?
When someone calls or emails to say I’ve got an Imola or Mugello and it’s blown up or it’s not right, or have you got a piston, it’s too slow or hard to kick over what can we do to help?
The first thing I say is ‘do you know which version it is? And the answers is ‘no or I think it’s a so and so’. I say ‘send it in or bring it in an we’ll have a look – thats all I can do because I haven’t much more of a clue than you’!
Most of the time the compression is too high and doesn’t like our modern fuels so the head needs the compression lowering. And over the phone which head is it? And it’s starts again, I ask what inlet manifold is it and again umm not sure, I ask what are the studs on the top of the barrel?
By this time …….. it’s still a case of ‘oh just send it in and I’ll check it over’.
This is a V4 I think!
But is different on the transfers feeds to the last one I did. The last one had empty space where the casing should have been.
This one the inlet, transfers and exhaust port that are all altered and flowed to suit the customer who wanted a fast around town motor for fun.
The head has been altered as it was over 11.5:1 so I’ve played safe as I like to if possible and lowered it below 10:1. This version only uses 3 mounting points for the inlet manifold, which obviously isn’t working here you can see chatter marks on both sides of the reed manifold, cylinder and inlet manifold, so I suggest in future these reeds get siliconed sealed to prevent this happening again.
But as a standard package the kits not bad I would just like to see some standardization in manufacturing, it’s a bit like an Escort mk1 to a mk 4 or 5 or 6 they are nothing like each other why don’t people change the name or mark it so we all know what we are talking about.
So don’t go and say I’m always slagging dealers off I’m just pointing out our job is not easy when things go wrong.
An Imola ready to be reworked in the transfer feeds
Inlet port ready to be flowed
Standard Inlet port ports ready to modify
This version has 4 extra bolt holes but only 3 is used
A standard center bowl head, check out how far away the plug is which needs altering
This version uses a recessed inlet manifold and cylinder, check out the chatter marks
This one has had a loose reed valve when run before, I suggest each side is silicone sealed
This version uses a cut down reed block to work
Lots of damage on a bad design
Modified lower compression head, the head standard is a little on the high side for todays fuel
Inlet manifold now flowed
Inlet port now flowed
Exhaust port modified and flowed
Transfers cleaned and flowed
Transfers inside the cylinder are modified, leveled and widened
Boost ports are modified
Exhaust port matched to the exhaust flange used
Mark Broadhurst if you have any questions emails mark@mbscooters.co.uk
