STFU racing

iTrader: (13)

I've been doing a lot of research and I drove all last year battling brake hop. I've improved drastically on smoother braking etc to help eliminate it but any upset in the pavement would cause it and send me into snap oversteer. Here is a list of things my set up has that clashes with brake hop. I'm wondering in what order do you think might help the most since for $$$ purposes, won't be able to do it all at once.

1. lca relocation brackets- Would removing my relo brackets and attaching lcas to stock location help reduce brake hop?
2. Replace my chassis mount torque arm with a longer tranny mount torque arm
3. proportioning valve
4. Don't plan on changing brake pads to cheaper ones.

anything I miss that might contribute?

brigade24

Front springs too soft?

79_T/A

iTrader: (1)

Your short torque arm is the worst offender on that list. Try a stock length one mounted on the transmission crossmember or a de-coupled torque arm. If your LCA's are level I wouldn't worry about them. What brake pads and front springs are you using?

N20zuki

What are you running for shocks and what kind of condition are they in mileage wise.

STFU racing

iTrader: (13)

I'm running Strano springs(550) with konis. I believe I'm 4 or 5 clicks from full soft on my front with a 35mm sway bar. I've had them on the car for 2 yrs now. Roughly 30ish autocrosses and no more than 500 miles highway use. I'm using Hawk HPS pads front and rear.

STFU racing

iTrader: (13)

anyone want to swap a UMI chassis mount torque arm for a full length?

camarokid91

Ditch the HPS in the rear or get HP + in the front. My car had hop super bad it was cause the HPS fad in front in AX then the rear will bit super hard and hop. Get some autozone pads in the rear and keep the HPS in the front.

STFU racing

iTrader: (13)

I'll try the HP+ in the front. Are you the same camarokid on Fraxx we have been fighting over dibs on a watts link?

what's your take on adjustable TA vs solid. I guess the adjustability is nice but I wouldn't know how to adjust it properly anyway. lol

jimmyblue

iTrader: (11)

Brake hop is the other end of the "box" you're in when
you're trying to force more launch bite with suspension
geometry. I don't see brake hop but have some hop in
reverse, with LCA relocation on the lower hole - with
a long torque arm, even.

At some point you can't get everything you want on
a fixed single torque arm and might have to go to a
decoupled setup (one for launch, another for braking,
never engaged at once). But this is elaborate and
maybe not necessary if you were willing to back off
on the torque arm geometry some.

Adjustability at the TA nose is one degree of freedom
you need for tuning the torque reaction. Adjustability
at the back only gives you the ability to get driveline
angle right, again, when you're done. Don't expect the
latter to help bite / hop, just vibration. And don't expect
the former to come without some NVH downsides (the
tolerability of which, is your tradeoff decision).

camarokid91

Yep. I will probably be giving Sam a call next month for one. I need to get my car ready for the DC Pro Solo in April. I believe the adjustable TA is primarily for drag racing to set pinion angle.

Sam Strano

iTrader: (41)

1 would help a lot. The more tail down the arms the worse it tends to make brake hop.

Item 2 is a no-no for helping brake hop. The shorter the TA the worse it gets. A full length one would help a lot.

3... A prop valve is not the answer. It might delay the onset of it. But we've been down this road. I could get cars to hop with the valve all the way closed (and different brands too), because the EBD in the ABS system will just bias more fluid backwards if it thinks it needs it. I ran a car for a year with a Prop. valve. Where it was set could delay and change how the car hopped but would not stop it. In fact there is no 100% cure for it, though with the way I setup cars it's not generally an issue (never was for me once I figured out some shock stuff even in F-stock trim and never an issue in my old 2001 car in ESP, was an issue for a while in a '99 WS6 until I figured some of this stuff out).

4. You don't want too grabby rear pads, and want a little more aggressive front vs. the rear. But that doesn't mean you can go full stupid on front pads and only slightly less so on the rear, that'd still be too much. I'm not a fan of junk rear pads. They still help stop the car. Typically I use HPS rears, with HPS front or more. I'm not myself a big HP+ fan, but if you like them then HP+ front/HPS rear is workable.

STFU racing

iTrader: (13)

Thanks sam. I used incorrect lingo. I currently have a short arm and need a full length that attaches to the trans. Ill be getting with you soon to purchase it.
If anyone wants a short torque arm. Message me.

Thanks for all the help. Ill be making those changes here soon and update the results.

1981TA

iTrader: (7)

I don't have anything constructive to add, but I'd like to say this conversation is teaching me a fair bit.

Running Hawk DTC-70 on front, EBC yellow in back, by the way. 12" rotors on all corners

FASTFATBOY

iTrader: (23)

"Snap oversteer" implies you are turning AND braking at the same time.

This is generally a no-no in these cars, you can trail brake a little to help the car turn in, outside of that get your braking done with the steering wheel straight.

There is no fix for this, it's a tap dance. Over pad the front and under pad the rear, Squeeeeeze the pedal in the brake zone until the weight is on the front tires then squeeeeeze harder.

If you overheat the fronts even with the cheapest junk pads you can find on the rears you will hop the rear if you are aggressive in brake zones.

I run my rear shocks full loose and the front compression on 5-6 to try to keep the nose up and the rear following the pavement, having the rears loose helps me get on the gas sooner once the car is done rotating.

I run 35/19 bars.

At 4:10 in this vid is snap over steer due to too much trail braking.

Sam Strano

iTrader: (41)

Trail braking is very much misunderstood (and done wrong. It's not about braking the whole way to the apex, it's about trailing off the brake pedal as you enter a turn. I think it was Mario Andretti that said something like it's the last thing good drivers learn how to do.

And anyone who never trail brakes will never be fast. If 100% of the braking is done straight, the car won't want to turn because as you release the brakes before turn in, the nose unloads and it doesn't want to turn. That said, too much brake also will not let the car turn (too much work for the front tires to handle).

Not an easy thing.

Looking at the video above, I'm not sure that was a braking thing. Sure didn't look like you were braking hard to me, and the way it snapped without any brake hop (which can in fact snap the car around as tires off the ground isn't ideal for grip) makes me thing maybe you just hit a patch of something on the track, but I'm sure. It looked odd.

JakeFusion

iTrader: (7)

I've been looking at running the stock F-Body calipers with the LG brake brackets (which allows use of the C5 rotors with F-Body calipers/abutment brackets).

Would the F-body's larger (44mm vs 40mm) pistons in the caliper, combined with the greater leverage of the 12.8" C5 rotor, produce more front brake bias, assuming the tires and pads are equal all the way around?

Would that help move some of the brake torque off the rear?

Sam Strano

iTrader: (41)

Ok, hang on before we go too far down this road.

You are not changing brake bias this way. The car's EBD (electronic brake distribution) will simply change bias on it's own when it thinks it needs too. Prop. Valves, brake pads, all that jazz will not change that. A Prop. valve will if you dump the ABS system completely, but not unless you do that. What the pads changes, prop. valves and all that do is change how fast the rear brakes react, not ultimately how much rear brake you will get. Don't waste your money.

What you need are a few things. Not overly grabby rear pads. A rear suspension that is not setup to make hop worse (LCA brackets and short torque arms will both make things worse). Good dampers, maybe even double adjustable ones so you have control over how the axle and body move speed wise vs each other.

Sam Strano

iTrader: (41)

Ok, hang on before we go too far down this road.

You are not changing brake bias this way. The car's EBD (electronic brake distribution) will simply change bias on it's own when it thinks it needs too. Prop. Valves, brake pads, all that jazz will not change that. A Prop. valve will if you dump the ABS system completely, but not unless you do that. What the pads changes, prop. valves and all that do is change how fast the rear brakes react, not ultimately how much rear brake you will get. Don't waste your money.

What you need are a few things. Not overly grabby rear pads. A rear suspension that is not setup to make hop worse (LCA brackets and short torque arms will both make things worse). Good dampers, maybe even double adjustable ones so you have control over how the axle and body move speed wise vs each other.

FASTFATBOY

iTrader: (23)

I have been trail braking from the very first sessions I did as a novice according to my first instructors....it just was a weird thing I figured out to help the car turn. It is a barge after all.

I was not braking hard when the car's rear stepped out, I was however trail braking, it snapped a fraction of a second before I was about to step off the brake and get back on the gas....I had a hair too much speed. If you are not going after more speed why are you out there.....right?

If you are braking hard enough with wheel input to make the car wheel hop.....you're doing it wrong. But you won't be for long because you will take your car home in a grocery basket doing it.

Sam Strano

iTrader: (41)

I might suggest a little more rear shock, and/or a 22mm rear bar, maybe a hollow one. That would help the balance a lot and lesser the need to "persuade" the car to turn so much.

This is my 2001 (now in Texas) with the 22mm rear bar, rear shocks quite a bit stiffer than full soft, my springs and a Fays2... and a few other things.
http://www.stranoparts.com/videos.php?VideoID=2

Oh yeah, and you'll notice no brake hop issues. No Prop. valve on that car. No LCA brackets (and stock LCA's but with the 1LE bushings), full length Torque Arm on the transmission mount as it's mounted stock.