Spongy Pedal after Brembo update

Suspension, brake, and hydraulic/electric steering discussion.
johnpz2721
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Spongy Pedal after Brembo update

Post by johnpz2721 » Mon Oct 28, 2019 12:02 am

I added Front 4 piston brembo calipers from a SS Camaro
I noticed now the pedal feels somewhat spongy ?
Bled brakes thoroughly any thoughts ?

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Mooseman
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Re: Spongy Pedal after Brembo update

Post by Mooseman » Mon Oct 28, 2019 1:05 am

I wouldn't think that any air got into the ABS unless the master cylinder ran low during bleeding. Might need to cycle the ABS with a scan tool if that's the case.
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johnpz2721
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Re: Spongy Pedal after Brembo update

Post by johnpz2721 » Mon Oct 28, 2019 1:49 am

Master never got low. When I lock up the brakes I don’t feel the ABS working ?

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Re: Spongy Pedal after Brembo update

Post by Mooseman » Mon Oct 28, 2019 2:04 am

Maybe try on a gravel road. Are the wheels actually locking up without ABS activating?
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Navy Lifer
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Re: Spongy Pedal after Brembo update

Post by Navy Lifer » Mon Oct 28, 2019 3:54 pm

What pads are you using with the Brembo swap(?) - that can impact pedal feel.

Just to be 100% clear, the calipers are installed with bleed ports at the top - yes?

I suggest you do another bleed - perhaps with a pressure bleeder - if that means having a shop do it, so be it....it's worth it.

If doing this DIY, did you have an assistant?

Are you using a catch container with clear tube, and is the tube submerged in fluid so it can't draw air back into the caliper?

Use a rubber mallet to tap on caliper body when bleed port is open, and watch for any bubbles in the fluid coming out.

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Re: Spongy Pedal after Brembo update

Post by CrashTestDummy » Mon Oct 28, 2019 10:01 pm

Navy Lifer wrote:
Mon Oct 28, 2019 3:54 pm
<SNIP>

Just to be 100% clear, the calipers are installed with bleed ports at the top - yes?

<SNIP>
All of Bill's points are good, but this one is important. We've had at least one member who got these calipers discover there are (LF) and (RF) stickers on these calipers, and it appears the calipers he got had these swapped, resulting in the bleeder screws pointing down. You'll never get all the air out of them with the screws oriented that way.

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Fudgehog
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Re: Spongy Pedal after Brembo update

Post by Fudgehog » Mon Oct 28, 2019 11:26 pm

LOL yeah that was me installed them upside down.

I initially had the spongy pedal issues, but I just had to keep bleeding them. I also ran the abs purge valve function but it did not tighten up the pedal.

If I recall correctly, I bled from right rear, left rear, right outboard, left inboard, right inboard and then left outboard.

I think it was alternating the inboard and outboard bleeders that ultimately got me good pressure. With one last bleed on the rear after I had the front procedure down.

Hope that helps.
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johnpz2721
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Re: Spongy Pedal after Brembo update

Post by johnpz2721 » Tue Oct 29, 2019 2:24 am

Bleeder Screws are on top !
I used a clear hose and a catch container to bleed
I thoroughly bled this with an assistant in the car
Pads are OEM Brembo I feel the stock pedal felt firmer !

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Re: Spongy Pedal after Brembo update

Post by Navy Lifer » Tue Oct 29, 2019 8:47 pm

Even with that, how is stopping power?

Are you using 355 rotors and earlier generation Zeta Brembo calipers, or 345 (OE PPV) rotors and current generation Alpha calipers?

Only other thing that comes to mind is whether GXP & SS, with fixed calipers, used a different pedal ratio than PPV's, so that response is different with Brembo calipers on a car with a brake system designed for floating calipers.

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Re: Spongy Pedal after Brembo update

Post by johnpz2721 » Wed Oct 30, 2019 12:03 am

Calipers Came off a 2017 Fireball 700 with 2000 miles Orig pads are still like new and I am using the stock rotors that come on a 2014 very spongy still

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