Alfa Romeo ONLY please!
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MD
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Re: Sprint/Trackday car advice

Post by MD »

OK Micke, I now see where you are coming from.

Probably started by my understanding that 164 's used the Brembo 2 opposing piston alloy calipers. Perhaps this is an Oz modification but I don't really know. The rotors and calipers were supplied to me for a conversion. Because the rotors were 164, I assumed the calipers were too but I must say I never checked that as there was no need to as the bolt up worked correctly straight away so I left it at that.

...so I wouldn't say we are not learning from this..I've just learned something new.
Go remove the brake pressure limiters and get 50% shorter braking distance.
Well I am assuming you are suggesting to do this as opposed to meaning don't do this. Either way my factory limiter is by-passed and there is a breaking improvement from the rear as a result. As to putting a % on it, I would estimate around 10% perhaps. Not experiencing rear lock ups in the wet either.

No doubt we are experiencing different results due to different tyres, pad formulations and other friction areas such a road surfaces not being the same world wide. So what works for me may not necessarily do the same for you. For example it is not the first time I have read that guys are using DS 2500 compound pads. These were a formula Ford reference track pad here. I have used them but didn't like them. For me, the Hawk pads work better. They are noisey and put out lots of black sheit on my rims - all the characteristic most people cringe about. As they say, horses for courses..
Transaxle Alfas Haul More Arse
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Mats
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Re: Sprint/Trackday car advice

Post by Mats »

Well, considering how much I had to adjust my brake balance just from switching pads I will never ever give general bias advice again.

I also question the removal of the bias valve, no way in h3ll I'd drive a car fast without it. Will only result in a spin in every corner. :?
Mats Strandberg
-Scuderia Rosso- Now burned to the ground...
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GTV 2000 -77 - Died in the fire.
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ar4me
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Re: Sprint/Trackday car advice

Post by ar4me »

Technically, you can have more rear brake bias in the rear as the overall grib reduces, e.g. in the wet. Less overall grib = less weight transfer to the front during (maximum) braking = greater contact patch at the rear tires = use it for more effective braking by increasing rear brake bias.

Same reason for Micke's point 2 on previous page. A track prepared car will have more grib = more weight transfer to the front during (maximum) braking = smaller contact patch at the rear tires = dial out rear brake bias for optimal braking.

Jes
87 Milano Verde - daily driver - Juliet
87 Milano 3.0 Motronic - budget race car - Roxanne
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(Repeat or do as I say at your own risk - be critical)
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SydneyJules
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Re: Sprint/Trackday car advice

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Thanks gents- all taken on board!

Yes I have been stewing over it. I figure, having my 2.5 the way it is, I should take advantage of it. Granted, in gpA days the cams were pulling a 900kg car. My goal is closer to 1100kg. It's still a road car and will simply be a weekend and supersprint car- not a proper racer. I've got enough engine while I learn how to drive (yes Mike, I am shit!), and the suspension has already got a bit done, hence, I wanted some simple changes to make it a little more track biased. The lexan windows and interior fix up will happen all in one go, and I can change the suspension stuff myself too.
I've got 16" wheels still on the car, so bigger front rotors an easy change. Semis won't bother me because it won't go out to the track on a wet day and I need new tyres for rego anyway. Simple. I will probably look at 225/50 falkens cause I'm cheap! I'm running pagid pads. They still work alright when they're cold for a road pad, don't squeal.
I'm pretty confident in my cooling system. It's like new.
28mm bars and some good A/R bars thanks Kev, and I will probably raise the rear of the car slightly and buy some stiffer springs. At $200 it's a pretty cheap mod. I just want to make the most of what it's got at the moment and give her a good tidy up.

I've just finished helping a mate swap his 253 V8 to a 308 in his Holden HQ ute, so I am owed a fair bit of labour!!!!

So I guess, with all those bits and a few others I will be on the right track to start enjoying the car and pushing the driving skills. I won't worry too much about other bits and pieces until the lap times stop falling!
Fixing it bit by bit....
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Mats
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Re: Sprint/Trackday car advice

Post by Mats »

SydneyJules wrote:So I guess, with all those bits and a few others I will be on the right track to start enjoying the car and pushing the driving skills. I won't worry too much about other bits and pieces until the lap times stop falling!
Best way forward.

Priorities always seem to change once you start driving.
Mats Strandberg
-Scuderia Rosso- Now burned to the ground...
-onemanracing.com-
-Strandberg.photography-

GTV 2000 -77 - Died in the fire.
155 V6 Sport -96 - Sold!
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