Eg6 Sir - Spec'98 Rear Brakes Lock up


G

Ghost EG-9

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Dec 6, 2009
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Hi,
Like the title say's: I've done a brake up-grade on my Eg6 SirII.
I've installed a complete brake swap from a spec'98 ITR.
Set up: Master cilinder and booster ITR 1"
Brained steel brakelines from Goodrich
Front and back swap from spec'98
And I also don't have ABS

Now the problem I've seem to have is when I'm on my rain tires ( Rainsport 2 )
and it's wet. When I hit the pedal to hard. On the rear they lock up.
With my toyo's r888 no problem so far.

Is it because me little car is to light? Knowing that the ITR is heavier on the rear. Or did I had to take the mastercilinder of an EK9? Because maybe the pressure regulation different in a mastercilinder from an EK9?
Is there possible solution for this?
I was thinking of installing some proportion valve's...

Is there anyone who has experience in this?
Anyway thanks for the help!
Grtz
 
Did you remove abs or is it a non abs model?

When I removed abs on my eg6 and fitted the bigger brakes & mc/servo, I used an itr non abs prop valve

I did not have a problem with them locking up but I was just running road tyres and not really braking very hard (no track use)
 
Ita probably the proportional valve, as when the front dives and the rear tyres lift they loose grip, so the prop valve backs of the rear braking pressure to avoid locking the rear.

Kozy will know exactly what to do! But maybe a non abs ek9 prop valve will accomodate for the latger braking torque your brakes are generating. Or install your own hard lines and a adjustable rear bias controller, but you will find the rear pressure needed for optimum braking will change depending on road conditions, thats why they use adjustable prop valves on track cars.
 
Rear disks brales are usually crap on civics! Harldy work since the calipers go rusty then start to strick. Now if yours are locking up you should be happy!

If you dont want them locking up, then remove the calipers and check if the piston sldes in and out freely. You will need a rewind tool.
 
It's a strange situation there. The wet setup typically needs more rear bias, because you can't stop as hard, there is less weight transfer, which means more weight on the rear tyres and more braking traction is available for them.

The fact you say it is fine in the dry with R888s is interesting. A perfectly balanced wet setup will become too far rear biased as you can stop harder, transfer more weight and reduce the traction on the rear tyres.

Your problem appears to be the other way round. Perhaps you're not fully utilising all the grip in dry?

This said, if you are still running on the stock prop valve, you should swap it for a 98spec non ABS prop valve which will match the setup. I'm not sure they are all that common, so the best option is going to be an adjustable prop valve. Unless you want to swap the routing and switch from a diagonal split to a front/rear split (not recommended), then you need one of these bad boys: AP Racing Twin Bore Proportioning Valve
 
I thought the 98Spec had ABS as standard though? Non ABS is a delete option and as such, quite rare?

I could be wrong.

Either way, and adjustable valve is best.
 
From what I have read the 98 Spec came with ABS as standard and they had to be asked to be built without just as Kozy says. My 98 Spec came without it as standard.

Although would a 96 Spec, which is more realistic to not have ABS, be easier to get a prop valve off?

That AP adjustable valve does look good though.
 
SRossi said:
Although would a 96 Spec, which is more realistic to not have ABS, be easier to get a prop valve off?
Click to expand...

Same 262/240mm brake setup as the EG6 though, so it won't solve anything.
 
Ok thx so what I need is a prop valve from a spec 98 without ABS
Now would a UKDM fit? Easier to find I think and the brake size is the same.
Or option 2 the adjustable prop valve, but I don't want to change the routing.
So if I install 2 singles, just on the rear lines the problem would be solved to?
 
Do not install two singles, there is no guarantee they will proportion exactly the same and you could end up with an imbalance over the rear axle. Get that AP unit I linked, it's the only way to do it properly, and you can then easily set the car up for wet and dry use.
 
Yup kozy has the answer, i knew i wasnt far off. Im looking at using the unit you linked kozy, as im not sure about running a front and rear split line for safety as my car is still driven on the road. I prefer the diagonal split.
 
Yes it's not recommended at all really, especially if you run braided lines as they are far more likely to fail than the standard rubber ones.
 
Kozy said:
Same 262/240mm brake setup as the EG6 though, so it won't solve anything.
Click to expand...

Ahh good shout, never thought of that but then that would rule out the UKDM one as well, even although they are impossible to find without ABS.

Best bet would be to go with the AP valve and have the ability to change it depending on conditions.
 
What are the differences between the 98spec valve and the std SiR EG6 one. I thought they came with a 40/40 valve.

Would assume an MB6 valve to be same as 98spec?
 
Ok, I will do it like that then, can I do it without changing the diagonal split?

So the prop valve from a spec 98 non abs is out of the question aswell, because it doesn't exists.
And any another Honda vehicule non abs with the same set up is out of the question to? I'm thinking Civic, Accord, Crv... Indeed perhaps MB6
 
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I would forget using an OEM fitment unit, there is too much ambiguity as to how they work and whether they are any different internally. The best way to approach it is that the stock prop is good for the stock brakes, change them and you really want an adjustable one to make the most of it all.
 
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