Brakes; too squishy, then too fast

Master_Scythe · **January 16, 2011, 06:58:19**

Hi all.

As i'm still looking for the exact i30 to call my own, i've been lying to dealers abuot planning to buy new in order to THOROUGHLY test drive one. Still happy.

Only thing i notice between them all.

The brakes start of very soft, and feel like they do nothing till about half pedal, then start to do something and feel almost like they're pulling themselves on. Like you've put rubber against the disk and its pulling tighter.

Does anyone know what I mean? Are there any mods to this? Firmer spring on the brake pedal maybe?

2i30s · **Reply #1: January 16, 2011, 07:14:09**

my cars have excellent brake pedal feel, compared to some of the cars I've owned.
and I've owned and driven a lot of cars. what are you driving at the moment?

Dazzler · **Reply #2: January 16, 2011, 07:57:29**

Quote from: 2i30s on January 16, 2011, 07:14:09

my cars have excellent brake pedal feel, compared to some of the cars I've owned.
and I've owned and driven a lot of cars. what are you driving at the moment?

My I30 had a gr8 pedal feel! My Camry Hybrid on the other hand, the brakes work well but because of the way they generate power to the battery (they feel like $hit)

eye30 · **Reply #3: January 16, 2011, 13:00:53**

Just touch mine and they activate, even after 3 years

**Reply #4: January 16, 2011, 13:11:11**

It takes a long while for the brakes to bed in. I assume you have been test driving fairly new cars... maybe too young to get a proper feel for the brakes. My brakes felt "grabby" for a very long time.

Lorian · **Reply #5: January 16, 2011, 14:53:56**

Agree, mine felt like on-off switches for the maybe the first 1000 miles or so, since then they have bedded down and now feel excellent.

Surferdude · **Reply #6: January 17, 2011, 08:12:42**

I felt my brakes were excellent from the beginning.
Progressive and effective.
I agree though there is a bedding in period where the pads don't quite completely grip the rotors.

Master_Scythe · **Reply #7: January 23, 2011, 01:16:14**

Right now i'm driving a Galant, its basically a VR4 without he turbo. So yeah the brakes are very good from stock.

Though after talking to another dealer. I figured out what i'm feeling. Compression braking. I'm testing diesels only here, and the feeling of 'brakes wont let go' is actually the engine pulling back as the revs drop, just like a manual.

I facepalmed when he explained that, of course thats what it is, i've been involved with trucks for a while; compression braking isnt new to me lol.

The pads themselves still felt.... shit... but the actual action of the brakes was fine, brakepads are a simple an cheap swap out.

Glad i got that one figured.

Dazzler · **Reply #8: January 23, 2011, 01:24:49**

If you look for Targa Tas and Rally West Threads on here you will see one of our resident Rally Aces (Razy) found some good pads to replace the OEM ones. Mick Gillett is also a member (another Rally Ace) and he might be able to suggest some good pads also..

TrishCW · **Reply #9: January 23, 2011, 01:25:21**

I've just test drove a new i30 cw didn't notice the brakes were soft, pick car up tomorrow will have a proper drive and test out the brakes. will be mindfull of them, thanks

rustynutz · **Reply #10: January 23, 2011, 02:13:26**

After seeing the title of this thread, I just HAD to post it...

TrishCW · **Reply #11: January 23, 2011, 02:18:41**

Quote from: rustynutz on January 23, 2011, 02:13:26

After seeing the title of this thread, I just HAD to post it...

I like that

rustynutz · **Reply #12: January 23, 2011, 02:22:25**

**Reply #13: January 23, 2011, 02:45:46**

Quote from: Master_Scythe on January 23, 2011, 01:16:14

Though after talking to another dealer. I figured out what i'm feeling. Compression braking. I'm testing diesels only here, and the feeling of 'brakes wont let go' is actually the engine pulling back as the revs drop, just like a manual.

Sounds like gobblededook to me.

2i30s · **Reply #14: January 23, 2011, 02:52:42**

yes,something smells a bit fishy. :o a salesman told you that.

Dazzler · **Reply #15: January 23, 2011, 04:44:44**

Quote from: Pip on January 23, 2011, 02:45:46

Quote from: Master_Scythe on January 23, 2011, 01:16:14
Though after talking to another dealer. I figured out what i'm feeling. Compression braking. I'm testing diesels only here, and the feeling of 'brakes wont let go' is actually the engine pulling back as the revs drop, just like a manual.
Sounds like gobblededook to me.

I seem to remember the Diesel did do that more than a petrol model at some speeds...

2i30s · **Reply #16: January 23, 2011, 04:50:15**

Quote from: Dazzler on January 23, 2011, 04:44:44

Quote from: Pip on January 23, 2011, 02:45:46
Quote from: Master_Scythe on January 23, 2011, 01:16:14
Though after talking to another dealer. I figured out what i'm feeling. Compression braking. I'm testing diesels only here, and the feeling of 'brakes wont let go' is actually the engine pulling back as the revs drop, just like a manual.
Sounds like gobblededook to me.

I seem to remember the Diesel did do that more than a petrol model at some speeds...

:o it may have less manifold vacuum.

**Reply #17: January 23, 2011, 09:49:30**

Quote from: 2i30s on January 23, 2011, 04:50:15

Quote from: Dazz on January 23, 2011, 04:44:44
Quote from: Pip on January 23, 2011, 02:45:46
Quote from: Master_Scythe on January 23, 2011, 01:16:14
Though after talking to another dealer. I figured out what i'm feeling. Compression braking. I'm testing diesels only here, and the feeling of 'brakes wont let go' is actually the engine pulling back as the revs drop, just like a manual.
Sounds like gobblededook to me.

I seem to remember the Diesel did do that more than a petrol model at some speeds...
:o it may have less manifold vacuum.

Quite a bit less.

They all need a dedicated pump.

2i30s · **Reply #18: January 23, 2011, 09:52:15**

thanks for that info pip,i didn't realise the manifold vacuum was much lower in the crdi.

**Reply #19: January 23, 2011, 10:24:13**

I could be completely wrong... but I assume it's because the inlet is always wide open so there's nothing to "suck" against to lower the pressure.

rustynutz · **Reply #20: January 23, 2011, 11:48:55**

I figure it's just the higher compression of the diesel compared to the petrol engine.... :-\

**Reply #21: January 23, 2011, 12:50:59**

According to this: http://en.wikipedia.org/wiki/Manifold_vacuum I think I'm right in my supposition. Might have overstated that all diesels need a pump, perhaps not all. Dunno about ours which I understand do have a butterfly valve which potentially could increase vacuum.

I think the butterfly though is just to "clamp" the air intake to prevent run-on/runaway when shut down so may only be activated (closed) when actually stopping the engine and therefore have no effect on overrun vacuum.

I've no direct knowledge.

EDIT: Just to add another thought. I don't think the butterfly closes on the overrun because the compression braking is so minimal. Anyone else notice that? I originally put that down to the small displacement. Never had a diesel before except in model aeroplanes.

rustynutz · **Reply #22: January 23, 2011, 13:20:28**

Quote from: Pip on January 23, 2011, 12:50:59

EDIT: Just to add another thought. I don't think the butterfly closes on the overrun because the compression braking is so minimal. Anyone else notice that? I originally put that down to the small displacement. Never had a diesel before except in model aeroplanes.

Now that you mention it, I have noticed it.....

And

to the diesel model planes, I'd forgotten all about them...