1480 Clubby Build (Now in Paint)
Turbo Mini Forums

why is that there?

custom steering rack???

looks like you're doing a flexible coupling, similar to a metro steering rack/column union.

EDIT: Strike that, it's up your inner wheel arch.

Edited by apbellamy on 28th Jan, 2011.

Big front AR bar?

Well done Tom its is in deed a Front ARB in the making the rest will unfold in the not to distant future.

what exactly is Front ARB?? :/

Nothing special!

anti roll bar

Paul, i'll put my neck on the line here, and say an ARB that big may very well have your car ubdersteering like an Audi,

also it can affect machanical grip on anyhting opther than a billiard table dramatically hence the undesteer .

been there, tried that , and it failed


carl

WWW.FORCE-RACING.CO.UK PLEASE CLICK HERE

I see where you coming from there Carl and I have designed it into the setup the ARB it's self is just a tube with two splined ends welded into it. My plan is to get 2 or 3 different size of tube and weld in splined ends and then go out testing to find out what tickness works best.

Looking good, would like to see some pics of the head too.

My I ask what’s the benefit of 6mm valve stems over a standard waisted stem valve..?

And is the head done by Slark Senior or Junior.

Si

Edited by Si P on 29th Jan, 2011.

I drill holes in everything..!

6mm stems make a lighter valve train with less harmonics

I seriously doubt it!

Hi Si the head has been with me for nearly 10 years now !!! and was originally done by Brian, as the years have gone on it has got progressivly closer to a full race head some of the work I have completed my self some of the work has been done by the Slarks I will get some pic up when it comes back from having its valves fitted.

6mm valve Theory:
As Paul has said one of the main advantages is that you get a much lighter valve train one of these valves, top cap and, collet only weighs 6.5grams
more than a standard 9/32 valve on its own !!
this reduction in weight also means you get to use a much lighter valve spring for a Given cam/RPM range. Which means a gain in hp and a reduction in over all friction in the motor.

It is a lot of money for very small gain but building high HP N/A A series motors is all about geting loads of tiny bits rather than looking for an illusive big bit.

Will be interesting to see what results you get from the anti roll bar.Looking forward to seeing the engine build.

Cheers Ross.

Cheers Paul x 2.

PaulH - have / they worked the back of the valve head itself?

I have some old slark valves senior worked, And he cut them way back towards the stem.

Interested to see what they,ve done with their new valves.

Paul W - I've been reading all that stuff from Graham Russell about Harmonics. And he comes up with this.
The big problem being that the crank can not be balanced over the entire rev range so you have to balance it for the rev range you work in,
as for the cam shaft the shock wave set up by the lobe wacking that valve open can only be cured by better cam design and valve springs,with the help of better harmonics coming through the engine,
It also amazes me the amount of people that think heavy valve springs rob power from the engine because of the force taken to open them,you must remember that for the one being opened there is another one being PUSHED CLOSE which cancels this out been there tried it many times
Graham Russell.

So valve train seems not to be to critical. Interesting don't you think.

Si

P.S. Interesting build by the way.

I drill holes in everything..!

Si that is an intresting Extract but to be Frank it is far to simplistic, Heavy Valve Springs do rob power and that is just simple Physics there is no geting around it if you think about it in terms of changing energy it makes more sense,
Friction is measured by its Coefficient,
ie: ų=w/f
so if we thak it that ų is the amount of friction we will place between the cam and the follower(and remember thats just one place heavy valve springs will creat more friction) and lets say w is the Weight of the valve spring so lets take a typical race spring over the nose at 240lbs and see the Friction of steel on steel is .4 I am not sure the excat value of cam followers but it wont be far off what do we get.

ų=240/.4 that is ų=600
and then for a 160 pound road race spring
ų+160/.4 ų=400

now if we put that against Grahams Theory we see that even if there is one valve opening and one valve closing it realy does not matter as the friction caused by the heaver spring is always going to be higher and thus will change more of the engines torque/power into Heat.

I'm not a big man on science but I know it if I need it and I know for Fact a lighter valve train requires less power loss to operate than a heaver one.

whats more I have only barely tuched on the losses her there is moment of inertia, concervation of energy nad much much more at play when you put light vavle spring V heavy.
regards,
PH.

Well put Paul H.

That was my thoughts. Friction is friction at the end of the day.

I'm in the process of doing an old school offset big valve head at the moment. And was just weighing up ( pardon the pun..) using 6mm stems.

Looking forward to seeing/hearing your results.

A valve pic would be nice though..

Si

I drill holes in everything..!

Good Peogress made today:

first started by choping out the tunnel to allow the driver seat move over to a better spot,


I then filled in the old hole in the floor where the gear linkage came through. Drilled a new hole and welded in some pipe the purpose of which will be revealed late,


I then to making a steering colum setup I am very pleased with how it has turned out the angle is perfect had to use 2 U joints but work out in the end,

Nice work, the steering column set up looks tidy.

well another little bit of progress this evening rollcage tags made and fitted need to do a few more but geting there,

Guessing game! Is the bit of tube for a steering rack gaiter to mount to as a flexible seal?

Nice work on the steering column by the way.

Cheers Ross.

Edited by rosco454 on 1st Feb, 2011.

Holy guess work batman that's exactly what it's for nice one Ross

Good idea! Do like the steering column looks real tidy. Been meaning to do this myself


Rich

2012 Avon class c 2nd place 13.8 @98mph

Progress is looking good! Is the scimitar your project aswell?