Are you sure it's not the brake booster flexing?
On my 88 I get 0.035" vertical deflection of the brake master cylinder with full pedal force. As much as I can generate. 150 lbs? 200 lbs?
This is with the stock firewall but obviously not the stock master or booster.
The Mule rides again (sort of) - pics.
Moderators: The Dark Side of Will, Series8217
- Series8217
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Re: The Mule rides again (sort of) - pics.
There are quite a few chassis that have similar issues. In many front engine cars, the far end of the brake MC can be braced to the shock or strut tower effectively, but that doesn't work in a Fiero.ericjon262 wrote: ↑Wed May 01, 2024 9:13 pm
apparently plates like that are a thing on third gen F bodies, and a bunch of guys are happy with the results.
https://www.thirdgen.org/forums/organiz ... brace.html
this is definitely worth keeping more in mind than I thought.
Maybe it is? Might be time for the Tesla electric booster conversion.Series8217 wrote: ↑Fri May 03, 2024 3:59 pm Are you sure it's not the brake booster flexing?
On my 88 I get 0.035" vertical deflection of the brake master cylinder with full pedal force. As much as I can generate. 150 lbs? 200 lbs?
This is with the stock firewall but obviously not the stock master or booster.
I need the plate as a way to mount both a clutch pedal stop and my DBW throttle pedal, so I'll finish it up anyway.
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Re: The Mule rides again (sort of) - pics.
Series8217 wrote: ↑Fri May 03, 2024 3:59 pm Are you sure it's not the brake booster flexing?
On my 88 I get 0.035" vertical deflection of the brake master cylinder with full pedal force. As much as I can generate. 150 lbs? 200 lbs?
did you check horizontal deflection too? this is an interesting observation, I know in my car, it appears as though the master moves a significant amount as I bleed the brakes.
I've seen several bracing methods, but without connecting the front wheelwells to the front frunk wall, I'm not sure there's anything there to really stop movement. I have a few ideas I would like to explore, but I am very intrigued by Series' posted information above, maybe I need to get an indicator out too...The Dark Side of Will wrote: ↑Fri May 03, 2024 4:37 pmThere are quite a few chassis that have similar issues. In many front engine cars, the far end of the brake MC can be braced to the shock or strut tower effectively, but that doesn't work in a Fiero.ericjon262 wrote: ↑Wed May 01, 2024 9:13 pm
apparently plates like that are a thing on third gen F bodies, and a bunch of guys are happy with the results.
https://www.thirdgen.org/forums/organiz ... brace.html
this is definitely worth keeping more in mind than I thought.
The "Tesla" booster is also in several other cars too, it's made by bosch, and accords got them too. That said, you posted in that thread so you already knew that...The Dark Side of Will wrote: ↑Fri May 03, 2024 4:37 pmMaybe it is? Might be time for the Tesla electric booster conversion.Series8217 wrote: ↑Fri May 03, 2024 3:59 pm Are you sure it's not the brake booster flexing?
On my 88 I get 0.035" vertical deflection of the brake master cylinder with full pedal force. As much as I can generate. 150 lbs? 200 lbs?
This is with the stock firewall but obviously not the stock master or booster.
I need the plate as a way to mount both a clutch pedal stop and my DBW throttle pedal, so I'll finish it up anyway.
https://www.realfierotech.com/viewtopic ... er#p161121
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Re: The Mule rides again (sort of) - pics.
0.016" horizontal deflection.ericjon262 wrote: ↑Sat May 04, 2024 5:18 pmSeries8217 wrote: ↑Fri May 03, 2024 3:59 pm Are you sure it's not the brake booster flexing?
On my 88 I get 0.035" vertical deflection of the brake master cylinder with full pedal force. As much as I can generate. 150 lbs? 200 lbs?
did you check horizontal deflection too? this is an interesting observation, I know in my car, it appears as though the master moves a significant amount as I bleed the brakes.
I have the stock Fiero pedal box with an E90 M3 brake booster and master. The adapter that consists of a steel tube and two flanges -- one with the Fiero 4-hole pattern and the other with the E90 2-hole pattern. The ABS module is connected via braided steel lines so the pipes aren't providing any additional bracing.
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Re: The Mule rides again (sort of) - pics.
I had a second, so I measured the deflection of mine as well, I'm getting around .020 vertical, I probably could have pushed the pedal a bit harder, but it seemed to deflect to .020 and then stop flexing.
"I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."
- Series8217
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Re: The Mule rides again (sort of) - pics.
Wow! On the '88 there is a steel brace that goes from the base flange of the master cylinder to the combo valve, which is bolted through to the left frame rail. Do you have that? I eliminated it with my master cylinder swap... I might need to bring it back...