Callumgw - 84 EXA

[Timmzy]

Yep. You are correct. We get back on the 12th, so I've just ran out of time and money to get it ready but that's cool I'll come down anyway. On the Saturday yes?

[Callumgw]

I'll confirm the day once I enter....

[Callumgw]

Just test drove the brake mods...just politely round the neighbourhood before a second bleed and handbrake adjustment. First impressions?



The master cylinder makes a big difference and I'm happy. I'd recommend it for anyone with a NA or Exa - doesn't work on the et master.

Now to make the bias adjustable.

C

[tassuperkart]

Cool.
Give me added incentive to actually fit mine!!!
E

[Callumgw]

yours is an NA right? . . . go the Prado master cylinder too!

C

[Timmzy]

Callum,

Nice work. They feel so much better with decent brakes hey? Its a confidence thing too i find.

Evan - don't use the ET setup its shithouse. Use the EXA setup (or just get the prado master cylinder)

Tracktime Callum!! Egggcellent smithers...................



Darren.

[TurboZ.Dude]

What are you guys using as balancing valve if you use an N/A style master cylinder with two taps? The N/A / EXA balancing valve with a couple of washers to re-adjust the front/rear bias for a setup of 4 discs ("Ben Hewitson's mod")?

[Callumgw]

As I said in my post earlier, the balance is the next thing to sort out. Ben said when ET disks are put on the rear the fronts did all the work and the backs did nothing, which is the safer situation. But all this will get validated in the usual extreme ways when it gets to the track!

I intend to have the backs do more work and would like to send more bias that way. To do this I think there is a smarter way to adjust the bias (proportioning) valve than washers, although they seem to work fine.

For the track setup, there may even be a way to make it adjust on the move. At this stage I think Kimmo has offer to donate a prop valve from his wreck to the cause. As ever I'll keep you posted!

C

[Kimmo]

Yeah, I could do that... but first I need someone to loan me an engine hoist : /

[Callumgw]

I'll get it out with the engine in place!

C

[tassuperkart]

Callum,

Evan - don't use the ET setup its shithouse. Use the EXA setup (or just get the prado master cylinder)

Darren.

Why?

L8r
E

[15exa]

Callum,

Evan - don't use the ET setup its shithouse. Use the EXA setup (or just get the prado master cylinder)

Darren.

Why?

L8r
E

was gonna ask the same question this morning, tho i was probably going to go way off tangent.

but i have to say the et set up is 2 fold better than the exa set up......
after doing it to mine recently, i was doing a fair rate of knots up the hi way, and pulled it up to 100 fairly quickly..... rekon if i had the old set up i would still be burring my foot down on the middle pedal.

[Callumgw]

I think the reason he's referring to is that the ET master has the 4 line master with prop valve inbuilt, so difficult to adjust and replace for a bigger unit. As you can see with the Exa set up, the remote prop valve and "common" 2 line master makes it easy to improve. The prop valve can (hopefully!) be made tuneable to suit the needs of the car and the mod's made.

Remember, all the mod's I've done weren't about stopping better, just more often with better pedal feel, Because as we all know:

Brakes stop tyres, tyres stop cars.

C

[TurboZ.Dude]

I think the reason he's referring to is that the ET master has the 4 line master with prop valve inbuilt, so difficult to adjust and replace for a bigger unit.

Ah, but of course! Should have thought of that. I was about to ask the same question as E...

Brakes stop tyres, tyres stop cars.

C

Good point

[Timmzy]

Hi Everyone,

Sorry I was talking about the master cylinders. I should have made that a little clearer instead of saying "setup".

Apologies for the offtopic Callum.

If you pull the ET master cylinder apart you will see it has 2 different piston sizes on the one mainshaft with diagonally opposed outputs to the wheels. (so 4 outputs from the master cylinder) These 2 different piston sizes setup the bias in standard form. With the 4 diagonally opposed outputs - my understanding is this is a safety feature so that if you lose a cylinder/split a line you don't lose that 'end' of braking EG: the front left and rear right are one circuit and the front right and rear left are another circuit. This keeps the car a little more balanced than if you lost say all front braking.

So if you want to adjust the rear bias in an ET (which is what I wanted) you would have to get 2 proportioning valves and install them on both rear lines. Additionally, you would also have to balance them in terms of rear left and rear right - which would get tricky. OR you would have to feed both rears into the one block, thru bias valve, and then split them up again. Once again. difficult.

My understanding of the EXA/prado master cylinder (Callum correct me if I'm wrong) is that it has 2 cylinders - 1 for the front and one for the rear. Much more simple setup if you want to fiddle with bias.

And lets face it. Bias adjustment is required if you:
- Upgrade front brakes
- Put ET discs on EXA rear
- Seriously getting into track racing

So its a little more common that you might think.

So if you are going to stuff around with master cylinders - Use an EXA or prado one as Callum has done. I am thinking of converting to a prado unit and pissing off my brake booster which is giving me grief on the track.

Darren.