The V8 Owners Forum -

:D Found it - Vizard uses a figure of + 10% on CSA of a round port to compensate for square ports. 845 x 1.1 = 930mm2 Which is 0.74 of the valve CSA - makes me wonder if the Bell figure should have been 0.76 of valve area rather than 0.67 - whatever it may have been 10% is a nice easy number to reme...

Well I have run the figures for a standard 40mm valve port and I come up with a port that should have A seat ID of 36mm - opening out to 38.8mm about 25 mm from the seat then reducing back to 34mm over another 25 mm then straight for 70mm then tapering out. What I am struggling to find at the moment...

Eliot wrote:You can score them off ebay easily:
search: "tungsten carbide burr"

plain carbide burrs wear out quicker.

I don't think I have ever seen the long shank versions or extensions on e-bay though. - Anyone seen these in the UK at a decent price?

Andrew

The long shank bits and collet extensions look very useful tools - I may risk ordering a few bits from Carbidebur.com in the US. I am also looking at the DIY flow bench articles and the like and fancy giving one of those projects a go. Anyone got any thoughts about how short I can go with the guides...

The only drawback with Dremel type tools is that if the tool bit jams then the motor overloads whereas an air tool just stalls. Just means that you have to take a bit more care.

Andrew

WOW :o - "Kid in a sweet shop look....." [/quote] Never seen before shot, consider yourself honoured: http://www.mez.co.uk/graphics/mez-tools.jpg [/quote] My next job is building an acoustic enclosure for the compressor - bit underrated so runs out of puff and has to motor continuously. Thanks for t...

I have the Des Hammil book and its quite usefull - as are the Hardcastle books and those together with an old Speedseries book by Vizard and the Speedpro book by Burgess there is some good reference material. I should do less reading and more practical :lol: I am not worried about guide damage as th...

Well I got stuck in with the burrs and sanding bands and I am quite pleased with the results A quick measure before hand had the port diameter behind the seat insert at around 33.6mm the seat diameter at 35 mm is now the main port restriction. As the casting "neck" further into the port has now been...

Looks like your dad was a gifted engineer and built up a comprehensive workshop over the years - I like the clock :wink: Having a long weekend this weekend and in between stripping the bathroom the carbides and calipers will be whirling about and I will use what I read about your dad as a bit of ins...

Cheers Eliot,

Was thinking something along more practical lines - I pretty much have all the theory - and just looking for the lazy mans porting secrets to a 500HP Rover -

Cheers

Andrew

Cheers Kev - The Speedpro book by Peter states 35 at the wheels for a 3.5 for the mods listed so I extrapolated a little. Its still a significant power to labour ratio for a bit of metal tickling :) Seats are 3 angle and look good enough to leave alone. No other secrets then ? - Had a quick search a...

Hi all Just about to take the die grinder and some carbides to the RV8 in an attempt to clean up the nasty ridges just behind the valve seats match up the ports to the manifolds etc. and grind the little ridges off the backs of the valves - the "Stage One" mods that are the mainstay of every tuning ...