I read a book on gas flowed cylinder heads and I reckon I can gas flow my cylinder head myself with a die grinder, some carborundum grinding paste and a polishing tool.

Good luck to you mate. Many people try this and some get a modest result and we can totally understand the pleasure gained from having a go and achieving something for your engine by something like this. Good on yer....

But....

- You won't be able to match 20 years of experience on the job with specialist tools using home tools and tips from a book. Gas flowing takes a lot of experience, specialist techniques and tools.

- You will not be able to measure flow and verify the result without a flow bench. It is quite easy to get worse flow (we have seen lots of gas flowed heads that do flow less than standard... sad but true)

- You will not be able to replicate flow across the cylinders by manual means without a flow bench, a CNC tool or a lot of time. If you can beat our results by these means, you are a genius. Please send a CV to Ric Wood.

- CNCheads do far more than a port polish job. It involves substantial re-profiling of the port with specialist tools and careful incremental measurement on the flowbench.

- and finally, as we know well, you could quite easily completely ruin your precious head by breaking in to the water circuit or making some other error, then you might be in the market for a new head anyway (and we may not be able to accept the exchange !!)