cuppa quick questions not solved by search

[r3dn3ck]

I'm a longtime hot-rodder, most of my modding is done to a 03 Mustang (built 5.4L swap, heads, cams, custom longtubes, complete race suspension, nitrous, cage, etc...) that I do most of the work on myself. In short, not a n00b. I know how to use a wrench.

I have a BONE STOCK 09 sedan SS and a couple things are bugging me that I can't get good answers to from searching the forums. I've been lurking for a few months trying to find said answers but decided today to say screw it and just ask.

Rear brakes are apparently an issue covered by TSB but I have a hard time believing the absolutely retarded tripe I'm seeing about a pad change being the issue. Pads being aggressive shouldn't be what's causing pre-load on my rear brakes and the rears shouldn't be contributing much to the actual stopping of the car any damned way. The squealing is a secondary issue and common to ceramic pads so I'm not really concerned about that bit. The rotor wear is phenomenally fast and that is a big concern.

What I'm looking for is some info on the stock brake proportioning valve: does it exist? Where'd they locate it? Is the garbage about pad compound/design really what you think is at issue here, etc...

Has anyone actually gone so far as to set up an aftermarket proportioning valve so we can dial in a little more front bias?

Is it just me or are the front pads full-on weak sauce?

Has anyone looked deeper into the setup of the rear brakes for things like mounting hardware irregularities, angles out of shape, shear angle, etc...?

Lastly, what sorts of reliability mods and free power mods are you guys doing? And by free, I mean free.

Finally, how do these cars take to nitrous? Thinking of jetting a nice little 50hp dry shot at it. As I understand it I'd have to have a tune to do so or the learn-down feature will start capping me.

 

[cobalt123]

ff drift lol or ls1fbody will most likely know this, give em a bit to come online. Yelloeye might was well. i myself have stuck to the lsj and l61s the lnf im a noob

 

[Revenant_SS]

Rear brakes are apparently an issue covered by TSB but I have a hard time believing the absolutely retarded tripe I'm seeing about a pad change being the issue. Pads being aggressive shouldn't be what's causing pre-load on my rear brakes and the rears shouldn't be contributing much to the actual stopping of the car any damned way. The squealing is a secondary issue and common to ceramic pads so I'm not really concerned about that bit. The rotor wear is phenomenally fast and that is a big concern.

Squeeling is common on ceramic pads? You've got that one backwards. We only use ceramic Delco pads in our shop because they are noise free. Of course, if everything is not lubed properly then you'll probably hear the pad vibration as a squeel.

And as the pads being the problem, that is correct whether you want to believe it or not. You can make a pad as aggressive as you want provided you don't let big chunks of metal make into the friction material which is why rear rotors get chewed up on these things. When you take a brake pad off and you see several shiny chunks of metal sticking out looking back at you, it's not hard to figure out why a rotor is scored.

I said f*ck the TSB and got my own pads & rotors and put them on in the shop a few months ago. I'm using Raybestos rotors and Delco 1095 ceramic pads. No more noise, no more scrape, no more scoring.

And there is nothing wrong with the brake bias setup either. It's the same way on a lot of newer cars. We did pads & rotors on a 09 Accord last week. 42,000kms metal on metal on the rear. About 40% left to the front. Done the same to an 08 Lacrosse and an 07 Camry about a month ago. They are setup that way to balance out nosediving on hard braking.

 

[1WhiteSSTC]

I've had my rear rotors/pads replaced under warranty once and b4 my LNF was hit by a gravel truck I was ready to call for a 2nd appointment for yet another rear brake warranty claim. I was going to let them do it all under warranty and soon as I got it back I was putting HP+ pads on the rear never got a chance to do that. I've got the HP+ pads on the front rotors, tho they were noisy as hell because the tech doing my pads for me didn't lube them properly. Once the HP+ pads were hot, WOW, VERY IMPRESSED, BAR NONE THE BEST PADS I'VE EVER HAD!!!! I wouldn't say stopping time was cut in half but DAMN NEAR!!! When the transplant is done I will be putting HP+ on the rears as well some better rotors all around.

Power for free on the LNF? Sry, none to be found. The closest you can get is the airbox mod, you need the silicone tubing which shouldn't be more than about $20 and then 2 clamps which you might have laying around in the garage. But again, that learn-down feature will kill any extra power until it's tuned. The LNF does not create extra power without being tuned, that's a fact that will never change, sry.

As for nitrous, dun bother, a tune with a few bolt on's like a catless DP, catback 3-inch exhaust, charge piping, and the airbox mod will net you over 300whp and SHOULD net you over 330wtq, on a custom tune, not the GM stage 1. I think you should try just a tune+airbox mod and see what you think after that, then if you still want more power there is always a turbo swap. Right now ZZP has their LNF Cobalt built to over 500whp SAE with a turbo swap, simple bolt-on's, and the right tune. Over 500whp FWD is absolutely tire shredding power the kind we all love.

If you have any other questions feel free to shoot me a PM and I will do my best to answer your question(s) and if I can't I will point you to the right person.

 

[ff_drift_lol]

Squeeling is common on ceramic pads? You've got that one backwards. We only use ceramic Delco pads in our shop because they are noise free. Of course, if everything is not lubed properly then you'll probably hear the pad vibration as a squeel.

And as the pads being the problem, that is correct whether you want to believe it or not. You can make a pad as aggressive as you want provided you don't let big chunks of metal make into the friction material which is why rear rotors get chewed up on these things. When you take a brake pad off and you see several shiny chunks of metal sticking out looking back at you, it's not hard to figure out why a rotor is scored.

I said f*ck the TSB and got my own pads & rotors and put them on in the shop a few months ago. I'm using Raybestos rotors and Delco 1095 ceramic pads. No more noise, no more scrape, no more scoring.

And there is nothing wrong with the brake bias setup either. It's the same way on a lot of newer cars. We did pads & rotors on a 09 Accord last week. 42,000kms metal on metal on the rear. About 40% left to the front. Done the same to an 08 Lacrosse and an 07 Camry about a month ago. They are setup that way to balance out nosediving on hard braking.

all very true. i've had some nice high quality cross drilled slotted rotors on all 4 with hawk hps pads. got it all from r1concepts.com for 400 shipped. i've had the setup for 40k and i can still see the non directional finish on the rotors and the pads are at like 65% i catch myself braking like a moron sometimes too. i take a nice 110-120mph pull every other day or so and usually have to stop pretty abruptly due to new york traffic. aside from that, i can see agressive pads doing exactly what they have been. tsb's are meant to only available to techs, so why would they bullshit us? all the consumer knows is they're getting their brakes fixed.

---------- Post added at 09:24 PM ---------- Previous post was at 09:15 PM ----------

I'm a longtime hot-rodder, most of my modding is done to a 03 Mustang (built 5.4L swap, heads, cams, custom longtubes, complete race suspension, nitrous, cage, etc...) that I do most of the work on myself. In short, not a n00b. I know how to use a wrench.

I have a BONE STOCK 09 sedan SS and a couple things are bugging me that I can't get good answers to from searching the forums. I've been lurking for a few months trying to find said answers but decided today to say screw it and just ask.

Rear brakes are apparently an issue covered by TSB but I have a hard time believing the absolutely retarded tripe I'm seeing about a pad change being the issue. Pads being aggressive shouldn't be what's causing pre-load on my rear brakes and the rears shouldn't be contributing much to the actual stopping of the car any damned way. The squealing is a secondary issue and common to ceramic pads so I'm not really concerned about that bit. The rotor wear is phenomenally fast and that is a big concern.

What I'm looking for is some info on the stock brake proportioning valve: does it exist? Where'd they locate it? Is the garbage about pad compound/design really what you think is at issue here, etc...

Has anyone actually gone so far as to set up an aftermarket proportioning valve so we can dial in a little more front bias?

Is it just me or are the front pads full-on weak sauce?

Has anyone looked deeper into the setup of the rear brakes for things like mounting hardware irregularities, angles out of shape, shear angle, etc...?

Lastly, what sorts of reliability mods and free power mods are you guys doing? And by free, I mean free.
Finally, how do these cars take to nitrous? Thinking of jetting a nice little 50hp dry shot at it. As I understand it I'd have to have a tune to do so or the learn-down feature will start capping me.

great idea! a bias bar would be a lot of fun, but for street use not so much.

i've been running methanol injection with a 100 octane tune for about a year, keeps my intake side clean and makes great power. (no dyno numbers but it just has plenty of advantages more octane is always better)
airbox mod works well, so does muffler delete. reducing backpressure and intake air turbulence is plenty of free power/response.
tuning is where it's at my friend. go 22 psi and you'll be eating tires for breakfast trifecta offers a boxed tune. hptuners is a program used for tuning, works well also and is much more personalized. a few problems here and there with fuel mapping though since its direct injection.

nitrous...at your own risk. it's aluminum, open deck block. i am assuming the 5.4 is closed deck? i don't know those engines for shit i work on all gm cars.

either way, you could slip by with a 50 shot un-tuned but it's not the safest thing. the rule is 2 degrees of ignition timing retard per 50 shot. i am used to the lsj (2.0 supercharged) so it's a shittier casting and i have seen my share of nitrous related catastrophic failure, but i'd imagine the lnf isn't THAT much better that it can take n2o with no tune.

 

[ls1fbody]

the problem with the rear brakes is in the slide pin.

Either it is not adequately lubricated, or it simply has no grease at all.

Pick up some new pads with a groove in the middle as the stock ones are smooth = bummer. Grease up the slide pins, which actually have a groove in them designed to retain the grease GM forgot to use

And as far as increased front bias, why? My car stops so hard it's ridiculous. Also, the front pads are Ferrodo. Pretty damn awesome pads IMO. They need to heat up, so it'll take more pedal pressure to stop on the street, but when you get going on a track/road course they'll get quite a bit more grabby.

You won't gain any "free" power with the LNF because of the learn down feature. Something people do for the exhaust is remove the muffler, adds a bit more aggressive note to the exhaust, but no gains. Well, maybe for one or two startup cycles, but then you'll lose that as the engine compensates.

 

[cobalt123]

i sure dont like that learn down feature

 

[ls1fbody]

Well, it's beneficial because it allows the car to perform to peak potential even in less than ideal conditions. Without that learn feature, the car would actually be less powerful in places like colorado when at higher elevation. It increases performance in a lot of situations. It's not just a blocker to aftermarket modification, although it does have that side effect.

 

[ff_drift_lol]

thankfully i can adjust my altitude with the interceptor. the slide pin you say? my buddy frank mentioned that as well. the TSB says the pads are agressive. this must be something an owner noticed. are the pads wearing unevenly and stuff?

funny you say no lube or not properly lubed, i guess some people just got their cars built on a friday or something. lol

 

[ls1fbody]

You know mike, i have also heard that the compounds used to make up the rear pads are too coarse, which also causes the uneven wear and deep gouges. The slide pins seize and cause the inboard pad to wear faster than the outboard.

There was a good thread on .nub. i'll see if i can find it and copy/paste