Matt87GTA

Why not just run the adjustable valve by itself?

Where in The State of Hockey are you at? Ever check the MNFBC out? (link's in the sig) Your car sounds pretty mean .

99Hawk120

Probably because he wants to retain the function of the warning light, and also because he doesn't feel like making his own splitter for the front two brake lines

wdigitog

hey larry...since you were with GM...i have a problem...i have 4 wheel discs...but the car started out disc/drum..someone swapped rears without changing the combo valve. i first noticed longer braking...then, with the rear end jacked up and the trans in drive, i couldn't stop the rear wheels from turning! totally no rear braking! i changed to new calipers, but still no braking. i think i'm going to try the valve mod to get 50/50 proportioning. i have a '83 z-28...i know the brake plumbing for that year was different...something about metric vs standard? do you know?

99Hawk120

82 and 83 used SAE lines, 84-92 used metric lines.

icecold

my rears were very ****ty-no braking to speak of in fact the parking brake system was stronger than the regular system.this mod works,but test it bacause as larry stated it's not a good thing to have more brakes in back than in front so you might need to add a adjustible valve to get things perfect.
matt 99hawk is right on i like the stock warning light.
i'm in the process of moving to maple grove right now i'm closer to lake osakis
pete

Auggie

I live in Maple Grove. Come on over and help me fix my brakes. I will buy the beer.

Auggie

Shagwell

I too agree w/ some form of rear mod. My '89 GTA was another w/ basically no rear brakes. I had an accident and then I got POed and decided to do something about it. Went out to a local airfield and started some 0-70-0 stuff. Nail the brakes, the fronts lock, and it's like you never hit the pedal! Wieght doesn't shift, and the rears do nothing. I ended up w/ 3 machinists washers behind the spring in my proportioning valve. My fronts lock just before rears. The car really clamps down now. I also tried switching the pv first, w/ Zero difference. - I am now switching out my stock 9-bolt and tiny rear disk to an 85 10-bolt w/ the 154 pad rear disc. This thing didn't stop for crap from the factory and I intend on making it better, before I finish making it faster.

later, justin...

Auggie

Well, someone said something about the rear breaks (drum/anti-lock) on a Dodge Durango, which i have. I jacked up the rear (both wheels off of the ground) and put the tranny in "D" and hammered the brakes. Nothing, the rear wheels kept spinning. I then adjusted the the brakes and tryed that again. This time I could here the anti-lock system click and the rearwheels stopped, but as soon as I steped on the gas pedel the brakes would not hold. Sound familiar??

Auggie

IROCZ4BD3

iTrader: (4)

?for anyone that has done this mod :where did you find this-->The threads on the proportioning valve plug is 5/8"-18. what I did was go to an industial hardware store and the only thing they had that would work was an allen head plug 5/8"-18 x 1/2"long.
I've searched everywhere for a 5/8"-18 x 1/2" long allen head plug and everyone says that there is no such thing.Which industrial hardware stores are you guys finding this?Thanks
BD3

87kevroc

My neighborhood Ace hardware store had it. I may have gotten it 3/8" long rather then 1/2", it fit perfectly. I used the teflon tape too, but am getting a slow (not fast enough I could tell a difference in fluid level) leak.

85TPI400

This is a very good post! I am about to give it a try...
Does anyone else have any problems with fluid leaks after making this modification?

TomP

Keep in mind, too, guys, about the 82-88 rear disc recall. Personally I think the recall parts should be put in first, and then decided if you want to mess with the prop valve. The kit's only $40 from gmpartsdirect.com ...

Auggie

Well, i did the update many years ago (1991) and heres all the the info: Dealer Product Campaign Bulletin (Recall) #86C28, Section #5, Date Issued 06-1991. Kit part #18019028. Cost at that time was $35.42. This fix helped somewhat but I still have bad rear brakes. I have a 1984 Z28 L69 (now 355) with (4) wheel disc's and my proportioning valve (P/V) does not look like the one in the drawing or in the photos?? My P/V preassure relief valve is located on the bottom of the P/V towards the front of the car, not on the end like the drawing and the photos show. Does anyone else have a P/V that looks like that??

Auggie

AGood2.8

I have edited this info in other posts- DON'T USE TEFLON TAPE- it will disolve eventually from brake fluid. Use thread sealant from Permatex. It holds up to brake fluid.

wdigitog

yes, my '83 z-28 has the brass valve with the plunger/spring unit located under the valve. it's the older unit and it usually is on disc/drum cars.

Auggie

Wdigitog, have you done the rear brake mod to your car yet?

Auggie

Aviator857

like everyone in the post my rear brakes just don't get enough pressure. On anything slippery My front wheels lock up and my rear wheels keep pushing me, until I knock it into neutral or pull the E-brake. I have drum brakes though, Has anyone tried it on disk brakes.

this has already caused me to bend a wheel, slid into a curb, and no I can drive and I wasn't going to fast the rear kept pushing me and I couldn't respond fast enough. I guess If I had a straight shift this wouldn't be such a problem.

I like most people have done everything trying to get them to work. I have new drums, pads, springs, adjuster, wheel cylinders etc, and It got alittle better, but like said above I can't stop the rear from spinning on jackstands unless I stand hard hard on the brakes. I am considering the 4th gen brakes on the rear. So with the adjustable prop valve can you get rid of the old one. GM wanted 95 for a new valve, I had came to the conclusion that this was the problem and checked on the price. If not I would have to put a new prop valve and an adjuster.


But you can tell when the rear isn't working on a car right it induces more nose dive. thus killing your braking and handling ability. Why do you think race cars spin out instead of sliding straight into the wall. The cars are set close to 50/50 which means under and ideal situation the car will slow down quickly, until you have wheel lock, then it comes to having to drive around what you are stopping for. This is called a race, and this along with speed is why you have a 5pt and a roll cage. But under road conditions you want the front to lock slightly quicker than the rear does on wet pavement. This is physics in its purest since, not only does a rolling wheel have more friction with the surface, the brakes can create more heat and thus dissipates more energy. The bigger the rotor/pad is the faster it can let the heat into the air, and the more stopping power the wheel has. Under any braking situation a rolling wheel will produce more stopping force than a sliding wheel. I have 3 years of physics classes to back this up with, I started off college as an engineer but decided I liked computer science better. I also have 2 friends that have graduated in aerospace engineering that can back me up, one of which has his masters from Georgia Tech.

average kinetic coefficient of friction for pavement and rubber is like .4 (sliding)
average static coefficient of friction for pavement and rubber is like .6 (rolling its static because although rolling the surface to surface contact points are considered to be in a relative kinematics frame and are not moving compared to one another)

It comes down to how built the suspension is to how much brake force you can put to the rear tires. Average production setting are 60% front and 40% rear. This is where the average driver that don't know a tire from a wheel doesn't do a 360 when he/she has to enter into a hard stop. The lower the car and stiffer the suspension the less the weight transfers to the front and the more you can use the rear for stopping. The more weight that is below the center points of the wheels the less weight transfer and nose dive the car has.

Well I got long winded didn't really want to get into your debate, and don't plan on it either. The bottom line is no matter what you decide test the car under several conditions in a safe area. You will then know you need to adjust it or leave it. You will also be aware of what the car will do.

In a big empty paring lot, privately owned one where you don't get reckless driving ticket. do this at your own risk

Take the car up to 35 at first, slam the brakes on in a straight line.
repeat this and try it turning to the right slightly, then alittle more
repeat this and try it turning to the left slightly. then alittle more

Increase speed and try it, don't go any faster than you feel safe doing in the area, and dont' run out of area

try it wet if possible

if at any point the car rear starts to slide on you before the fronts are locking you probably don't have it in the safest config. Make adjustments and try again. Now if you jurk the wheel 1/4 to 1/2 turn while slamming on you brakes you would spin out an indy car so do it consisident with how you would drive on a daily basis.

I have done this in my car and was never able to get the rear to lock.

85TPI400

Thanks for the info Good2.8, I had a feeling brake fluid would eat through teflon tape eventually, since it doesnt have much of a problem eating through paint...

wdigitog

no, auggie, i havn't done the mod yet. i did buy a new prop valve from inline tube. they say it has the same fittings as my car and is a direct replacement...for a disc/disc car....we'll see. it's more expensive than the mod though...$ 100!

AGood2.8

wdigitop, the whole new replacement valve (GM # 14089496- 1LE valve for pre-'89 1/2 cars with square style valves) is the best way to go. The "quick fix" I posted here is for the people that can't afford the cost of a new 1le Prop valve- It is a fix designed to at least give working rear pressure, even though it may not be balanced right, its still better than nothing in the rear working at all. (I, as most, would prefer the rears locking in the rear easy as opposed to them doing nothing.)

I ran this "quick fix mod" on my car for several months. It worked great for awhile. Problem I had is that the fronts started to fade over time and pressure was dropping on them because of valve wear. Consequently, the rears began to lock sooner and sooner in relation to the fronts so I eventually did the 1LE valve swap. I know a few that still run the mod and are still working great front and rear.

Dean

wdigitog

really appreciate the head-up dean. thanks

25THRSS

This thread has been very informative. I think I'm going to go ahead and gut the stock valve and install a wilwood valve as well so I can dial the brakes in as best as possible. Where should I put the adjustable valve though?

99Hawk120

As the directions say, you put the adjustable in the rear line, after the stock PV.

kdrolt

TTT and FYI.

As briefly mentioned somewhere above, the alteration of the brake combination valve is often done on 94-96 Impala SS and Caprice police 9C1 passenger cars that have 4-wheel-disc brakes because the factory used the same combination valve on them as it used on the regular Caprice that had disc/drum brakes. That means the front:rear brake proportioning isn't correct, and that's what led to the modifications.

Now on an Fcar that already had 4-wheel-disk brakes, you have to see whether the combi valve was the same, or different, than the one used on disc/drum Fcars...... before you alter anything.

AND it also helps a lot to test the car on a brake plate dyno like the one made by Hunter (drive the car onto 4 plates and then lock up the brakes --- it measures the forces at each wheel and helps diagnose brake problems.) Those type of brake measurements, plus infrared thermal measurements, plus engineering analysis have been done on the Caprice/Impala situation but it's not obvious that any of that was done here on TGO as it applies to the Fcars.

So my $0.02 is to READ the following links --- because they apply to the subject here in this thread (even though the links are for the Bcar and this is an Fcar board) and make sure you know what you are doing before you alter the braking system. And do not confuse faulty brake hardware (stuck calipers, weak hoses, dirty fluid lines, corroded slide pins, glazed pads etc) with a chronic defect from the factory.

http://impalassforum.com/cgi-bin/ult...;f=23;t=000632

http://www.impalassforum.com/cgi-bin...&f=23&t=000252

http://impalassforum.com/noncgi/ulti...=001099#000002

http://www.impalasuperstore.com/nais...s=metering,mod

askulte

Just to clear up a few misconceptions posted above... When braking, you get weight transfer to the front, no matter if your suspension is set up stiffly, or as soft as a factory V6. Because there is much less weight on the rear tires, you have less traction available in the rear, so you need that much less braking force/friction at the rear discs.

Here's a quick calc:
Assume a max of 1g, with a center of gravity height of 19", 3600 lbs, and a 55%/45% F/R weight distrubution.

Weight Transfer = Height of CG / Wheelbase * Weight * Decelleration in g's

Weight Xfer = 19 / 101 * 3600 * 1.00 = 677 lbs

With 55/45 weight dist, your 1980 lbs front and 1620 lbs rear now go to:
2657 lbs front and 943 lbs rear.

That's now 74% Front and 26% rear weight distribution.

Friction Force = coef of friction * load

Assuming you have the same size tires front and rear, your rear load goes is much less than the front (note - tire coef of friction isn't linear w/ load - it decreases slowly with more load, which is why we want to minimize our front weight %). Having a 50% front/rear brake bias (dead even front to back) with identical brakes (that's not true, but is fine for this example) gives you ***MUCH*** less total braking force available in threshold stop.

In a real world situation, you want the front and rear brakes to lock up near each other. Having one end lock up way before the other is giving up a lot of potential braking force. Which end locks up first is personal preferrence, as seen above, but most road racers I know like to have the front lock up just a hair before the rear.

One other thing to consider before disabling the OEM proportioning valve is that on slippery conditions (ice, even rain), your total braking decelleration is much less. This means you have that much less weight transfer. Since you have that much less weight transfer, so more is on the rear wheels, where they can proportionally do more of the braking. Racing setups w/ dual master cylinders and a balance bar have a fixed front/rear bias, which you change based on available traction. OEM brake setups have the spring in the combination valve that depending on the braking force, theoretically has 50/50 front/rear braking initially (gentle stops) that as you increase braking pedal force, decreases the rear percentage, so you have more braking up front under hard decel. OEM's didn't calibrate the system for different brake sizes/pad materials, R-compound tires, etc, so that's why everyone is tweaking their combo valves and adding extra brake proportioning devices. Phew - way too long winded. Time to get back to the shop and finish the road racing brake duct hats...

kdrolt

Askulte's post, or rather the math behind the post, comes from summing forces and moments and setting them to zero (I've done the same analysis for the 94-96 Caprice/Impala before -- he is correct). The effective front:rear weight distribution goes from 55:45% static (either no stop, or a very gradual stop) to 74/26% in a full-panic stop. Intermediate braking would give values between these two.

The Impala/Caprice(9C1) tests at 95/5% front:rear on a Hunter brake plate dyno (a machine that allows the percentage front/rear to be measured directly). That's on a factory stock car (either Impala SS or on the police model Caprice 9C1) with no mods to the braking system. After modding the combination valve, the front:rear proportioning goes to around 75/25%, which is much closer to what it should be based on the static weight distribution and a full panic stop.

NONE of that necessarily applies to the Thirdgen Fcar. It applied to the Caprice/Impala ONLY because the factory used the same combination valve on them as it did on the disc/drum non-police Caprice. So if you plan to alter the braking system on your 3rdgen car, for whatever reason, DO YOUR HOMEWORK and make sure you know what you are doing FIRST.

fb305svs

Stock brakes.... 91 TA, PBR rear's with the 12" rotors ect, stock prop valve nuthing done to the braking system at all except maintence...

http://www.ss-perf.com/videos/cartedited.wmv


notice the rear end sliding out a bit under hard braking and the corection i had to make... yes, it is not much at all, but that thing woulda been *** end into the trailors if i had to much rear brake in it.... carfull guys, just be carefull...

RTFC

Thats not brakes, thats your cars suspension unloading rear to front.
Individual things that will help:
1)Set your rear rebound higher and/or set your front compression higher- in other words, you need higher vavled shocks for what you are trying to do.
2) stiffer front springs
3) Your car is lowered from stock height. Whatthis means is your front roll center has lowered MORE in proprtion to what your rear roll center has lowered. You roll axis is inclined towards the nose more thus you *** end will lift as in the video under hard braking.
To truely dial you car in for Autox you NEED to lower your rear roll center and get stiffer springs and shocks.

When that is all reset properly to you suspension changes, your braking problem in the rear will misteriously disappear.

fb305svs

Well, i didn't want to go into chassis set up - a lot of arguements with people could be had lol - however, i helped set up chassis for local race cars around here for a few years, so i have a pretty good understanding about chassis setup

the car also has much bigger rubber all around, and at the time, when i did that autocross, the tires on the back were no good (they were dry and old... and since were replaced lol)

That was also my first run through the course and i played with the shocks all around and it made a big difference

in this car, when i did the spring change, i measured the chassis hieghts before and after - i actually lost more chassis height in the back than the front- 7/8" if i remember correctly... i think this is mostly due to having a lot of weight off the front of the car from stock - alum heads, fiberglas hood, ect. This car when i put on the scales was running only 51/49 with a half takn of fuel for front to rear weight bias... not too shabby!

i'm working on getting the car set up for the track more than the autocross. since putting new tires on the back, the loose issue has gone away. the front is going to get stiffer springs as well - as you said, the car comes down too hard under load in the front, and i have the stiffness on the shocks cranked up. they are hotchkiss springs, i need to pull one out and go have it rated and see what it is, whether or not its progressive and get the exact height of the current srping. i don't want or need to drop the front end anymore.

Thanks for your advice though - very good from just seeing the video - but i have already done some of that list since the vid






In regards to my post however - how the car behaved in the video is how anyone elses car, who hasn't taken the time to adjust it properly would act - hence the warning for people - regardless of the fact that the slide of the rearend in that vid is two fold - braking and chassis set up...

RTFC

*edit*
Forget it, not worth the arguement. Enjoy your "racecar".

fb305svs

dunno what you were gonna argue about, i basically agreed with you... i was just stating thats how the car was before anything was adjusted or set up, wasn't trying to aruge!

RTFC

You would probably be upset with what my response was going to be to your response of setting up cars and how you think you car looks in the video.. I'll keep it to myself. Enjoy your car.

Thats why I said it is probably going to leadto an arguement, I have now said too much. Rather than giving the response you did to my "helpful criticizm" about your video, maybe you should post the next run and what the corrections you claim you did made the car look. If the car has performed much better than that video, then why would you not show the best Video you had? I certainly would want to show my car at its best. If you did make the proper corrections and had something better to show, it certainly was not from you making any brake system adjustments.

The subject here was about braking proportions and you put that link claiming you had braking trouble. I told you that braking was not your trouble, your braking was fine, its you suspension that needs help. So basically your first post was misleading and wrong about brake propertions and how you were warning everyone to be careful what they do in regards to brake adjustments or they "could" lock the rear like you are. Sorry but thats wrong info.


*edit* I just find that people around here misinterpet my typing that I am attacking someone and being mean when I am merely giving helpful tips. Most people I have concluded take offence to what I say as if I am giving a superiority complex. I just state what I see and give correcting info- when I am wrong, I willingly admit when I have made mistakes in the past- I am not arrogant.

fb305svs

Thanks, i definately will - If there is one thing I have learned about the internet, it is that if someone makes a post bashing or contradicting or whatever about something you said, you probably just didn't make things clear enough in the first place...

Well, unfortunately, that piece of video was taken from a clip that someone posted from the event. I had no idea who the person was who took the video, nor did they turn up any other clips of the car. I would love to post a video of the car doing better - it was downright crappy in that run.


Well i would love to, but unfrotunatly, i don't own a camara, nor do i really know anyone that would get up early on a sunday to come to the autocross with me

Well, your sort of correct; The reason i posted the video was to show people that the stock bias is pretty adaquate under an untuned suspension - Not that i was having braking trouble. I feel that most people here who have simliar parts as i (springs, LCA's TRQ Arm, shocks), would never take much time other than playing with there shock adjustments (if they bought adjustable shocks to begin with).

I felt the video applied well to the usual scenario that most thirdgen owners with simliar mods might face.

I agreed braking wasn't my trouble... i obviously was unclear and unexplaining of how the vid i posted applied.

People in this post were talking about their rear brakes not producing enough braking power due to the proportioning valve limiting them. I thikn the video is a great example of how our cars may handle under a heavy braking load with just simple mods. Not many have adjustable shocks, and not many go out and stiffen the front springs on their cars. However, many have probably had an animal run out infront of them and have had to swerve under heavy braking....

I haven't yet insinuated that your hav ebeen arrogant, nor am i feeling provoked for an arguement, nor do i feel offended. Personally, i would rather have a technical discussion about brake proportioning and suspension setup rather than let things die. There is a wealth of good information in this post about suspension and brake bias that you may not find in other suspension posts. My experiance is in circle track racing, and limited at best in road course racing. Although there are some commonalities of HOW to get a car to behave a certain way, the two setups are no where even close. Nobody in there right mind is going to put a 1300lbs spring in the RF, a 950lbs spring in the LF, a 225 in the RR and a 175 in the LR to get a car to turn both directions lol... not gonna happen! Needless to say you tend to want to run as little crossweight as possible in a roadcourse car, unless of course you want to bias the car for more of one direciton of turn, and you certainly are not going to 55% left side weight!

Anyways, i never have a problem admitting mistakes, i think that i wasn't clear as to what i was trying to say/show. maybe in a couple weeks when i get back to autocross (damn working weekends) i'll find the guy who took the video and get some more. The car no longer swings the back out, although like you said, it definately needs stiffer springs in the front

fb305svs

you have a picture of this by anychance? i'd like to see how you mounted it..

RTFC

It is so refreshing to have a respectful conversation. Thank you very much. I was not insiuating towards you at all, I am merely being caustious due to my bad experiences in the past leading to troubles with others, not yourself. I am just trying to be more aware of what I type and how I type it and I was coming off alittle too cautious with you and you are obviously mature enough I see now to understand- may bad- and my appologise.
Now to the subject

The rear roll center adjustment will of course help dramatically on a V8 car going into a corner under braking, however, with the softer front springs it will cause the car to be harder to turn. So in my "advice/or opinion" (Everyone's got one )I would definately recommend upping the front spring rate and the front rebound rate if you decide to add the Jegs relocation bracket.

Here's a shot of it. I bolted and welded it in place inside and out. I just don't like the idea of a bolt-on critical suspension link with that much leverage on it.

Also, here's a link to my car on course. It has very stiff springs, hoever, I do have very low roll centers and I have more leverage than factory on the front a-arms since I set the offset of my custom brake setup as outboard to the fender lip as I could comfortably without contact. The front has a very low unsprung weight for a full time streetcar with a very lightweight 60*V6. Notice how smooth it rides on course.
Third

RTFC

Forgot the pictue of the Jeg's panhard relocator. Here you go.

Ps- In case you are unaware also, I am the guy that stated this post a few years back. I used to be Afrikingoodtime, and a few other names around here.

laiky

Now that i have seen actual video of Dean's car, i feel even sicker and more depressed about not being able to work on my car this summer

fb305svs

Ahh ok - was more curious as to which side of the panhard you mounted it on... on the stock car, we had an adjustment on both sides, although we tended only to play with the frame side mount more than anything else.... much easier to do when purpose built of course... In fact we used a slightly different setup on the frame side - basically it was a piece of roll bar tubing welded on with bracketry and ect so that it was straight up and down. The end of the pan hard bar had a clamp of sorts that would clamp onto the verticle piece of roll bar to allow us some more fine adjustment... it was fantastic, and very usefull for a circle track car.


we always phrased it this way when trying to explain what we were doing when we would go up or down on it - rasing the bar would help free up the car in the middle of the corner - IE more or less giving it less grip, raising the roll center. if the car was having trouble turning in the middle of the corner - this is the adjustment we would make, unless we found our chassis hieghts were off (had jacking bolts on all 4 corners in it) moving it down would be what we would do if the car was entering and exiting ok, but was loose in the middle... we used cross weight adjustments to help with corner entry and exiting... which you can do on a car meant to turn one way, not both. Very intresting to see the other effects the rear rollcenter had, we never really used it for adjusting corner entry even under braking because it's effect was so much more felt in the middleof the turn for us.

Unfortunatly for me, i'm not going to be able to lower the car much more than it already is in the front, as i run longtube headers... the exhuast clearence is ok, but i hit once in a while. By anychance do you know the spring rates on the hotchkiss springs? i may do a search after this post. I think the very first words out of my mouth after driving the car around with them in was that they were far to soft.... good for the street, not so good for autocross...

One thing i do want to invest in is the upper strut mounts in the front - does anyone make them these days? of would i be better off having a spacer made up? it never made sense to limit the travel so much in the front like that... IMO it makes it difficult for the shock to work properly, as they rely on the movement to work well.

Also, what do you run for caster / camber / and toe #'s? and did you ever measure to find out the bump steer on it? just curious... I'm assuming you have

About the engine - it is nice to have that smaller motor in there... we all know roadcourses are not much about the power... it helps, but the car needs to turn more importantly lol. My car has the front end lightened up some - a fiberglass hood, and aluminum heads help quite a bit... the car is surprisingly almost neutral on the scales from front to back....

fb305svs

I love this site - found the spring rates for my springs...

part #1903 - 82-92 fbody - Front rate - 600, Rear rate - 100-140

i have a few spring wedges - i may have to play with them and see what kind of results i get.... nobody will have an issue so long as they are wired to not fall off on the track i think i think they are good for 75lbs of spring rate... i'll have to look at them. we used to use them on the circle track car when we were dialing in the new chassis. would show us which way the spring needed to go. just used to safety wire them in so they wouldnt fall out heheh.

RTFC

Rather than typing alot, let me just give you some links to look at. Spohn is now making billet STEEL strut mounts I would highly recommend them.

This car is my wifes daily driver, it is not a purpose built autox car by any means. That video was on 2/12 year old and worn street tires Goodyear GS-D3's and the same exact "street" alignment that she drives the car daily and got 25,000 miles out of the Goodyears including me using it a day here and a day there on various tracks very rarely.
Alignment is -.80 camber and +5*l/ 5.5*r caster and 1/16 toe in.
I have aligned the bumpsteer as best a range I can get it. The front suspension does not travel more than 1 1/2" max travel under the hardest bumps- mostly only 1" The dirt buildup marks on the struts do not lie, I do not bother with dustboots in Sunny So. Calf- no raod salt, very dry and clean mostly.
http://www.cardomain.com/ride/518752

As for this car's agility- You can read these posts of all the local guys that were shamed when I took every one of them by a minmum of 3.9 seconds and up. They were all V8 3rd gens. You have to ride in this car to understandits agility being a V6. Even this car is not 50/50 so I highly doubt you are even close unless you have massive weight in the rear added. For te record, not even an aluminum LS1 is as light as this little V6 motor and I am also pushed further back in the engine bay being shorter. All the motor weight is behind the front wheels.

This is were the story begins- the smack talk: https://www.thirdgen.org/techbb2/sho...hreadid=303194

This is the conclusion- the enlightenment : https://www.thirdgen.org/techbb2/sho...hreadid=306260

And the posting of everyones Video's- I embarassed alot of people in my wife's little slooow V6 with worn street tires:
https://www.thirdgen.org/techbb2/sho...hreadid=307528

fb305svs

Thanks, i'll read up - i know the v6 is light... i am gonna have to go and weigh the car out again... last timei weighed it i think it was 53/47... i think without me in it... i dunno was last fall, i dont remember lol.

moneyman380

So you are not suppose to do this mod if you have 89-92 rear brakes? If so why not?

I have a 91z28 and the rear brakes dont work worth a damn.

IROCZ4BD3

iTrader: (4)

RTFC-Would you recommend the panhard relocator on all lowered cars?I already have a adj panhard bar that was installed and setup before installing the Eibach Prosprings.

v6#21

Yes I would. Where on the list of importance in buying aftermarket parts would I place its purchase? I'm not. I am simply stating it has its benefits on every car as a tuning tool and yes most need it to get the suspension balanced

midwest

Instead of finding a plug, just take out the spring, and the rubber seal on the piston. Then put the piston into the end plug, and install the plug back into the prop vavle only screw it in a few turns, now pull the lid off your master. Fuild and any air will escape past the threads,you can see the air come out, now tighten the plug, top off the master, check to see if your pedal is soft. You will find that its not. No more bleeding necessary.

Now go for a test drive, test the brakes, before you get any speed. If they feel fine, go for a 25mph drive, and slam on the brakes, you should feel a difference, also watch the speedo, if it drops to zero and your still sliding, it means you brakes locked up.

On my car, i have 11.5 inch rear rotors, with pbr calipers. I aslo have 275/50/15s in the rear and 225/70/14s in the front. When i brake hard, the rears lock a split second before the fronts. I did this mod while it was raining, and went for the test drive while the roads where wet.
I did a few panic stops to feel out its manners. Even while turning the car would slide straight or at a slight angle, at no time did it feel like the back was going to slide out and cause loss of contol. This is just how my car worked. You car might be different.

Fastime

http://auto.howstuffworks.com/auto-p...ter-brake2.htm

http://www.gofasst.us/brake_proportioning1.htm

some interesting reading

86irocterror

i dont want to argue with anyone over this but wanting the rear tires to lock up with or just after the fronts do is a BAD idea. anyone watch any form of auto racing and you can see even your top of the line race cars lock up their brakes and only the fronts lock. a general rule of thumb is you want 70% of your braking done by the fronts and the other 30% by the rears. and alot of that has to do with the weight tranfering to the front. even if you only had rear brakes on the car the weight will still transfer to the front making the back even lighter and cause even less tire traction to help stop you. and the fastest way to stop a car is to NOT lock them up!

G8T8A

Those are very good points. I wish I knew how the design of these cars matches up to that rule of thumb (70/30). I am one of those that when the car is on jackstands, the rear brakes will not hold the wheels AT IDLE. To take it out of Drive and put it into Park, I have to put it into Neutral and let the brakes halt the wheels, then quickly shove it into Park skipping Reverse quickly enough to keep the wheels from going in reverse.

I don't want road-racing brakes for driving in the rain, but I wish I had properly working brakes! My GTA gets driven very little, and it's just never a priority to fight and figure this out. There's not enough time in the day.

Napster134

"Then I used teflon tape on the threads and wrapped it around twice and inserted it into the original plugs' location and tighted it until it stopped.(as tight as you would tighten a caliper bleeder valve- do not over tighten)." - AFrikanGoodTime


I was wondering... what is the difference between doing this mod and installing an adjustable prop. valve? I mean the adjustable prop valve is pretty much doing the same thing isnt it? The tighter you go, the more pressure that will be allowed to build up and well vise versa, if you loosen it off then that would relief some pressure and cause your brake to not be too great.

The instructions say to tighten it until it gets tight... well wouldn't it make more sense to say, tighten it until your rear brakes lock right after the fronts?

FlippindaBird

iTrader: (10)

this thread is awesome! i dont care who's right ive got an 87 disc/drum brake car that i swapped the rear to a '02 SS rear with the discs... im thinking of getting rid of the valve alltogether just replacing it with a piece of pipe... if it dont stop, i got tripple A