• We've upgraded and reskinned the forum. Notice something off? Email us at [email protected] and we'll fix it.

V1 Add-on brake proportioning valve

KSLunsfo
I also have a square setup and with my valve bottomed out counter clockwise I'm still close to the edge of the rears locking up first. I have to really try to make it happen, but I do think the rears just do want to lock up first. It seems I'm somehow out of adjustment to get just a little less rear and more front. Not totally sure why...

Edit:
43166

So, somehow I must have had my logic messed up. I guess with where the valve started before I began making adjustments was towards the least front bias (full CCW, out). I THOUGHT I was getting less rear lockup as I was adjusting it but perhaps it was changing just enough with tires heating up that it only seemed that way...

Anyway, I turned the knob a few full turns CW(in) and now it definitely stops noticeably harder. In the one drive so far with several hard 30-0 and 60-0 stops I haven't had any tires lock up yet.
 
Last edited:
KSLunsfo
It's also worth mentioning I'm running the Wilwood manual master with no booster.

What this has me wondering is if putting more caliper up front would put me in the right range and still leave suitable adjustment in the prop valve to just barely get the fronts locking first... This is assuming I don't have air somewhere or something else strange going on. I wouldn't say the pedal is spongy by any means that I can tell...
 
Desert Sasqwatch
In all seriousness, contact Wilwood and explain what your situation is. Maybe someone there has an idea about getting a mid-engine car set up better? Can't hurt to ask, worst thing that can happen is they don't have a good answer.
 
Davidljones88
I did one stop test today and measured 60-0 in 94ft. Federal 17inch 225s and 245s tires, 85 degrees outside. I dont think I came close to locking the wheels up at all and feel like I could have applied more pressure. I have the brake proportioning valve but haven't tested different settings yet.
 
KSLunsfo
I updated my post above... Picking up with that comment here:

I turned the knob a few full turns CW(in) and now it definitely stops noticeably harder. In the one drive so far with several hard 30-0 and 60-0 stops I haven't had any tires lock up yet.

However, one of these 60-0 stops I encountered some pretty severe wheel hop or just where the front wheels were jumping around like crazy. The car was still tracking straight but it definitely LOOKED sketchy. The road surface may have contributed to this to some extent but not positive.

Link to a thread on this issue:
https://dfkitcar.com/forum/index.ph...nd-hopping-under-hard-braking-now-fixed.1820/

I've only skimmed through that thread and it seems as though for Ross anyway, that the progressive springs were the answer to this... I do have the correct tie rod ends on the front and do not have my A-arms adjusted way out or anything like that.
 
KSLunsfo
With a 2 stage powder coated frame I would hope I don't have to add said triangulation... I do have new shocks on the rear (the option from DF) and the extended track frame. I'm still on all the original springs, shocks etc from DF (front and rear).

How often did you experience this wheel hop? So far, it seems I have to try pretty hard to get this to happen. But I can see how I don't want this to happen very often if ever...
 
Last edited:
KSLunsfo
Right. I mean the road is not exceptionally rough there, that was just one factor I was considering. The wheels were definitely appeared to be coming off the ground though. One thought is that perhaps I need to increase my dampening up front. I've already turned that up quite a bit just now, but still need to drive around a bit and see if I can replicated it or not. I'll report back as I learn more.
 
KSLunsfo
Well no real improvement there, worth a shot right?!

With things quite a bit firmer I was able to replicate the wheel hop. This time less severe, but likely due to being prepared for it and letting off sooner. Not too sure where to go from here...
 
KSLunsfo
True. I do have the MOOG bushings that I pressed into the rear control arms as I was first putting the car together. Otherwise, I may have already noticed issues back there as well.
 
Ross
Try stiffening the rear shocks. They have most of the goblin's weight on them, and will affect the stability on the front.
My issue was hard braking from 100mph, with sticky 275mm tires.
You have the full 3 bar sides on your car, and a track frame, which is a lot stronger than my easy entry frame, and it was a city frame.
 
KSLunsfo
I will definitely try that out. My tires are so-so sticky, they're Pilot Sport 4S's, 275 all around. Likely doing something like the R888s next go 'round...

Reminds me, my build log is considerably out of date.
 
KSLunsfo
Ross said:
Try stiffening the rear shocks. They have most of the goblin's weight on them, and will affect the stability on the front.
My issue was hard braking from 100mph, with sticky 275mm tires.
You have the full 3 bar sides on your car, and a track frame, which is a lot stronger than my easy entry frame, and it was a city frame.
Click to expand...

So, the rears were basically around full soft. I moved them to approximately the middle (I counted something like 34 or so total clicks from full soft to full firm). Wheel hop is still occurring with semi aggresive to agressive braking unfortunately...
 
You must log in or register to reply here.

Similar threads

duthehustle93
V1 LSJ Fronts+Solstice Rear: Brake Prop Valve Front/Rear?
Replies
3
Views
762
duthehustle93
duthehustle93
Indy Lonnie
V1 Manual Master Cylinder Pedal Ratio
Replies
5
Views
1K
Keckster
Keckster
RETNAVY
V1 #243 FOR SALE TEXAS $ 22,500
Replies
0
Views
255
RETNAVY
RETNAVY
RobC76
V1 SOLD Turbo Charged / F35 Trans - Extended Track Frame - Chassis #247 - Under 100 Miles - $19,000
Replies
0
Views
1K
RobC76
RobC76
Ross
SOLD: Brake proportioning valve and brake lines for a SC or NA goblin
Replies
8
Views
2K
Rttoys
Rttoys
Back
Top