19 replies to this topic

[ryomini]

Martin you are correct I have a 3.1 FD and my car does 100kph at 3000 rpm and 110kph at 3500 rpm but if you like the accelaration I would stick with your 3.44 FD, if you can get your head mildly ported and the correct volume for each chamber, with a good cam, flywheel and exhaust you should find things just a bit zippier - any change that you are going to really feel comes at a heavy price

 

a 7 or a 8 port alloy head is the price of some people's car alone

 

I am not yet convinced by the 1.5 rockers as they put a lot of pressure on engine parts and have been the cause of breakage

 

a cheap way to get a fast road mini is to just drive harder - I mean how many of us push our mini to the edge anyway.  Some of the fast minis on youtube are 30 000 dollar plus cars

 

by the way it's the 'custom shift knob' that really makes my car fly, lol

Edited by ryomini, 15 October 2016 - 12:31 PM.

[martin_mini]

Martin you are correct I have a 3.1 FD and my car does 100kph at 3000 rpm and 110kph at 3500 rpm but if you like the accelaration I would stick with your 3.44 FD, if you can get your head mildly ported and the correct volume for each chamber, with a good cam, flywheel and exhaust you should find things just a bit zippier - any change that you are going to really feel comes at a heavy price

 

a 7 or a 8 port alloy head is the price of some people's car alone

 

I am not yet convinced by the 1.5 rockers as they put a lot of pressure on engine parts and have been the cause of breakage

 

a cheap way to get a fast road mini is to just drive harder - I mean how many of us push our mini to the edge anyway.  Some of the fast minis on youtube are 30 000 dollar plus cars

 

by the way it's the 'custom shift knob' that really makes my car fly, lol

 

Ryo, quick question do you oversize your valves (35/29) or standard valves (33/29)?

[Turbo Phil]

Fitting the larger 35.6mm inlet is definately worthwhile. But it's essential to deshroud the valve to get any real benefit. With a deshrouded chamber and a 30 degree back cut on the valve flow is improved vastly up to about 0.350". For the small amount of work involved this makes a decent improvement.

Phil.

[ryomini]

Martin,

I guess mine are standard as I haven't changed or measured them

and I agree with Turbo Phil there is something to be gained getting the valves cut professionally, and there again more money for a teeny weeny little gain - it all adds up in the end, hp and the hole in your wallet, plus if you try too hard you will need to build a better gearbox, the mini box is not designed to take a lot of power

[Turbo Phil]

The thing is it's not a "teeny weeny gain" though. If you have access to a lathe it takes about 15min to do the valves and makes a very worthwhile gain. The chamber can be deshrouded yourself with a drill a carbide and a stone and takes about 10minutes a chamber. With both these simple mods the 35.6mm valve really starts to work well.
I have flowbench tested all these things myself so I've seen the results first hand.
The valve, seat and the chamber around it are the primary restriction and should be your number one goal.

Phil.