Rear disc conversion - is it worth it?

[dumpycorsa]

Hi. I've got a nova SRI fitted (shortly) with an approx 200bhp xe. I've got a nova rear beam thats been converted to discs and I've bought a brake bias valve. I'm in the process of finishing my engine conversion. Yesterday, whilst getting my carbs rejetted I spoke to a chap who races minis (has done for many years). I was talking to him about my car. I mentioned I had rear discs to go on and a bias valve but his instant reaction was don't bother. He said with a light front wheel drive, heavy engine up front and stripped out interior you won't need hardly any braking pressure on the rear wheels. He said he converted a mini to discs before and by the time he had the right brake balance he had to use 2 bias valves in line to reduce the pressure enough.He also said that if you disconnect the rear brakes on his mini you wouldn't even notice the difference. Once the rears lock up you're off the track so it's not worth the risk. He also said sell the rear disc conversion and spend the money on getting the castor/camber setup properly. This is where you'll gain a great deal in terms on handling. Whats your opinion?

[craig green]

He spoke utter sense tbh.

However it sounds like you are nearly there with all the bits to do it. On the plus side, the 16v rear discs are simple to maintain, more reliable than the drums as they waer the pedal feel can soften etc. If you use the proportioning valves from the disc equipped donor car (assuming non-ABS) the bias should be right.

Personally I did it for looks & the fact that performance cars have discs all round. When your car is pretty much sorted, you do things for the sake of it.. rear discs maybe, being one of them.

[dumpycorsa]

I can understand the ease of maintenance side of things and discs are generally more reliable etc. I have noticed with a couple of the novas I've had the rear drums can lock just one wheel when you first brake in the mornings. If the shoes wear unevenly this could also be bad for brake balance.

Discs are more pleasing on the eye but if it's just about looks...

[Fridge]

If it's locking one wheel early in the morning, it won't do it for too long as it'll soon wear and not rub anymore :).
I think the front's do somewhere in the region of 90% of the breaking (Pub figures?) so you don't NEED discs at the back, but i would do it. Always good to just throw it out there in the specs list "2ltr Corsa, uprated suspension, discs all round.....etc"
And if you've got it already, why not fit it?
As for setting up the castor and camber angles, it will definatly improve things but i think you'll need to invest in some adjustable suspension parts to start with!
Look for a few of the track-day-guys threads such as oli(dhev) or trackdaynova, if you trawl through their extensive projects you'll see what you can do to improve suspension set ups.

[dumpycorsa]

Rose joint tie bars and eccentric top mounts you mean? Thats what I was going to get any way. As the car is going to be mainly road but with a bit of track I can't go too mad.

I've got the beam all ready to go on it's just I'm fitting my poly bushes at the moment and I'm not going to fit them into the disc beam if I'm not going to use it.

[Adam]

They look good.
But thats about it..... Lol

And just how much do you have to service drums anyway? I know i aint touched mine yet and ive been driving the car 3 and a half years.

[Fridge]

yeah that kind of stuff, i can't tell you an comprehensicve list as i'm still to do it myself yet but look through the track day threads.

Maybe even some camber alignment

http://www.demon-tweeks.co.uk/products/ProductDetail.asp?cls=ROAD&pcode=EIBE5.81250K

[Fridge]

"an comprehensicve" ?!?! I sound drunk.