Write-Up: F-Body Brake Mod

oh I forgot. The hubs may not work either. I think the threads are reversed on thee 97 since the are secured by a bolt from behind.

well i have been collecting parts for some time now. trying to get the best possible deal on each item because i'm a broke college kid . I almost have everything needed to transform the entire front of my 96 riv to a 1998 riv with f-body brakes.

This is what i have so far:
eibach STS lowering springs
camber bolts
strut top mounts for 98 riv
upper spring seats
97+ steering knuckles
used hubs with knuckles
reman/rebuilt f-body calipers
f-body caliper brackets
bushings and hardware
DOT 4 fluid
new rotors (chinese
new pads (morse)
KYB's and lower spring seats will be in this week

Here is what i still have to buy:
SS brake lines ($60)
alignment ($80)


i dont really have any questions, but i wanted to at least post up so i can update it as i go along.

i dont think we need a write up on anything since we already have one for f-body upgrade and for new struts. but i would be happy to take pictures of anything if needed.

i cant wait to see how this tank corners and stops! going from 150k miles worn out mounts and springs with little 10" rotors, and single piston cast iron calipers to stiffer, lower, brand new suspension parts, 12" rotors and dual piston alum LS1 calipers!


-Matthew

If you email or call ZZP they will sell the front SS hoses only for about $58.00 IIRC. email Zoomer and ask how to order just the fronts.
Make sure they are 20" long..
I found the cost of the SS hoses to be cheaper than replacing hoses with rubber OEM type Raybestos. If your rears are original hose's, I highly recommend you replace those also while doing the upgrade. Cheap insurance.

zzp lines they love to leak, on my second set only after 2 months. look into oem rubber ones or goodridge. I also hope you are drilling and tapping your f-body caliper brackets...using sleeves is almost a sin with us w-body guys.

where can i find goodridge SS lines? pfyc lists stoptech lines, but doesnt have any G-body in the list.
can you elaborate on this tap vs sleeve idea?

I don't know where to find Goodridge lines for our car. But remember your looking for lines that will fit a Bonneville, not the Riv. I don't know what year range Bonny's fit. Maybe ZZP list the years, i can't remember now.
I haven't had any issues with ZZP lines leaking and i think others on here have bought SS lines from them without problems. Maybe just the ones for the Grnd prix have problems, I don't know.

Regarding the drilling and tapping that he's referring to is to drill out the caliper bracket's and spindles to accommodate the stock Riviera bolts which are larger diameter. Again, I don't think it's necessary on our cars. The F-body bolts (provided they are of the proper hardness, M 10.8) which yours are, are more than adequate and the spacers from McMaster (INA) are also hardened are good for our installation. In my opinion no need to open up the hole sizes and tap new threads.
But since you have the spindles off you can consider having a machine shop do that work for you. You will need to remove one of your stock bolts to measure the diameter and thread pitch, it is metric.

Mr.Riviera wrote:

where can i find goodridge SS lines? pfyc lists stoptech lines, but doesnt have any G-body in the list.
can you elaborate on this tap vs sleeve idea?

^with the goodridge lines they tend to be a little short, honestly stainless brake lines are over-rated, if i could do it all over again i would have just stuck to oem rubber ones.


as far as the drill and tap vs. sleeved...There has been way to many instances to list where the bolts backed out with the sleeve method, bolts loosen the caliper and leaning into the wheel, leading to an extent amount of wheel damage and wheel lockup. Basically the f-body caliper bolts are smaller on the LS1's, with your riviera and my grand prix the bolts are larger, some may argue but the correct way to do your brake swap is to drill and tap your f-body calipers to match the bolts for your stock caliper brackets. Im not sure what size caliper bracket bolts you use but you can take them and your f-body caliper brackets to any local machine to get them tapped to the correct size, for me i spent $10 on the bit, and $20 for him to do the labor, a small price to pay for safety

p.s make sure you use blue locktite on your caliper bracket bolts.

I grabbed a set of RickW's calipers, now I've got a couple questions -

What's the difference between the 12" rotor f-body brakes and the 13" W-body store brakes? Brackets? Can the brackets be purchased anywhere if I want to upgrade to 13" rotors?

vendetta wrote:

so I could potentially have a corvette brake setup for 2-300$, or just ls1 brakes for almost free!

What's the difference between Corvette brakes and LS1/F-body(same thing?) brakes?

I don't know anything about the 13" set-up, but I can tell you the LS1 with 12" EBC rotors and pads feel like a corvette brake set-up.
You won't be disappointed.

corvette brakes are 4 piston calipers.
f-body calipers have 2 pistons.
same brackets AFAIK.

you'd have to ask oldsman about the 13" rotors. i believe he has them for his bonneville.

I don't know about the EBC stuff, specifically the comes-and-goes braking power depending on whether the brakes are warmed up or not.  I've had some scary moments on the 1 lane country road I live on.  Naturally everyone drives it like they're the only one on the road since it's remote.  So when you do meet another driver it can be a split second, life or death thing.  I don't need to be in that situation with cold brakes that don't grab.

I read on another forum that the f-body brakes cause increased pedal travel (which doesn't happen with the Corvette calipers).  Has anyone noticed this?

C5 brakes on a, uh, Impala? -

Link

I have not had the experience of the brakes coming and going or requiring warm up before you get excellent stopping power.
I think that was mentioned when using EBC pads with stock rotors.
Regarding increased pedal travel. I've had just the opposite experience. After installing the LS1 calipers with the SS brake lines my pedal is high and much firmer at all times, during all types of braking. Maybe the ones experiencing a softer pedal have not bled all the air out of the system.
IMO, I think you should try the LS1 calipers and SS brake lines before buying corvette calipers., then if your not satisfied you can always change later.
BTW, I purchased the Dimpled and Slotted EBC Rotors and the Red Stuff pads for the front and I think the green ones for the rear.

Quote :

I don't know about the EBC stuff, specifically the comes-and-goes braking power depending on whether the brakes are warmed up or not.

It's not that bad, really. I've not noticed this to be much of a safety issue at all. The only time it ever happened was on very long trips in very cold weather with zero braking, which lets the pads and rotors cool off. Most of the time you hit the brakes once every 5-10 miles. That's enough to keep them sticky. The added performance of having the extra stopping power and durability far outweighs the slight lag that happens under 1% of the time in the coldest weather. In warmer weather, it never happens.

The reason is chiefly the pad compound, which is rated much like a spark's heat range - you need to pick the one that works best with your set-up & driving style. Also, the vented EBC rotors do help cool down the system very quickly, contributing to the "issue" some I guess. And it works the same way for all pad brands: faster biting pads are the cheaper "OEM" spec that like to operate cold. "Street/Track" pads that are made to work hot must be warm to grip best. "Race" pads are dangerous if not hot when working. If you are worried about it, downgrade to an OEM spec pad, problem solved. You'll notice they are less effective at very high speeds, but very good in day to day driving. The Hawk HPS pads I use have noticeably better grip from an 80-100 mph hard stop than during gentle stop and go stuff. The slow stops aren't unimpressive, it's just that to high speed performance is so much better, imo.

As for the added pedal travel, I do think there is some substance to this, and although I don't mind it personally, I do think it could pose a problem for some drivers, particularly down the road, when pads have worn down some.

AA wrote:

As for the added pedal travel, I do think there is some substance to this, and although I don't mind it personally, I do think it could pose a problem for some drivers, particularly down the road, when pads have worn down some.

I personally have had the opposite experience after changing the calipers and hoses.
I have much less pedal travel during all driving conditions. I thought it was a dramatic improvement over stock brakes the first time I applied the brakes.
I've gotten used to the decrease in travel now and can modulate the brakes without activating the ABS.
In my case it doesn't take much foot pressure at all for the brakes to bring you to a stop quickly.

speaking of race brakes...
working at a car wash, we get all kinds of cars coming in to get detailed. i was pulling one of the Titan WRX's around and didnt realize it had full race brakes. after washing them off with cold water, needless to say they didnt work well. i was pulling the car into the detail bay (probably faster than usualy due to the car i was in) and hit the brakes, but it wasnyt stopping! it felt like i was in an old rusted out 60's mustang with manual drum brakes. i almost hit the car infront of me . very unsure feeling.

i dont really have a point to my story, but if you only use your riv for cruising and dont plan on exceding the posted limit you can probably save your money and get a good set of ceramic oem pads.

however, the ebc (ond other lke it) semi-race pads seem to be quite an improvement over stock pads. if i had the money i would order a set for my upcoming f-body install. i went with friction master pads insted.

Dont ever get full race pads to use on the street

as far as how the peddle feels... the "spongy" feeling some people notice with the fbody setup is due to having 2 large pistons. the C5's have 4 small pistons which is suposed to feel about like stock. if you keep the rubber lines, and dont do a full bleed to get rid of air and old fluid i could see it not feling very well. but i'll trust what the members here say about it way before i believe what somebody on clubgp says.

O.K., I feel reassured now.

Do the Vette's 4 smaller pistons make a huge stopping power distance over the LS1's 2 larger pistons? I'm not terribly likely to buy the Vette brakes instead, I'm just curious.

Up through 2004, C5 Vettes used near identical calipers to the F-Body, save for the "Corvette" name cast in the side (a nice touch, imo). These are aluminum, 2 piston calipers that should bolt up no problem.

Starting in '05, C6 uses a near identical caliper (deleted cooling fins) that's also 2-piston, beefier for less deflection, fits C5 and F-body mounting bracket. Uses same pads as F-Body & C5. Front rotors are 12.75".

The Z51 C6 uses a different bracket to accommodate a larger 13.38" rotor, but caliper and pads are identical to C6, compatible with C5 & F-Body. The Z51 set-up needs at least an 18" wheel.

C5 Z06 Calipers were same as C6, but painted red, as far as I can tell.

The C6 Z06 used 6-piston fixed calipers (3 on each side of the rotor). These are very expensive ($900+), and probably require special mounting brackets and bigger wheels.

I'm not familiar with any 4-piston calipers for modern Vettes. C4s were a 2-piston design as well.

maybe i was looking at the upgraded vette brakes then. i was under the impression the C5's had 2 pistons on each side of the caliper.
a quick part compare: they look the same as the fbody ones, except for the painted "corvette".

why would clupgp say that the vette brakes had better feel than the fbody ones?

They probably say a lot of stuff. The only reason I'd get them is because they say "Corvette".

However, Corvette owners seem to see a difference even between C5 and C6 calipers, as one member of corvetteforum posted:

"The C6 caliper has more material in the right places (mostly on the bridge) that keeps it from flexing nearly as much, or nearly as quickly. C6 front calipers can last for many sessions at Road America before spreading. C5 ront calipers last one or two sessions.

C6 front calipers can last for MUCH longer than C5 fronts. This saves money so you don't have to replace calipers as much, and you don't ruin nearly as many pads from uneven wear caused by spreading.

This isn't about rotors, or any of the rear stuff.

The pads used are identical. You don't need to replace your caliper bracket- the C6 caliper will bolt directly to your C5 bracket using your C5 slider pins.

You can pound on the brakes at a place like Road America with the C6 caliper alot harder for more laps, whereas with the C5 caliper, it is done after a couple of HARD qualifying laps."

Quote :

We've done testing on them all...

The C5 caliper is not compatible with the F Body bracket and the C5 bracket will barely clear the stock 10.9" rotors so using the C5 calipers is going to require some modification.

The volume of the F body caliper is larger than the W Body and results in longer pedal travel before the caliper engages. This is why people commonly complain of a long pedal with the F body upgrade. The C5 caliper volume is smaller and pedal travel is improved over the F body.

The other nice thing about the C5 calipers is that they are pressure cast which makes them exponentially more resistant to deflection than the F body calipers. That's good news for anyone that does repeated, heavy braking.

Quote :

The C5 caliper/ bracket will barely clear the 97' - 03' 10.9" GP rotors. Despite being designed for a 12.7" rotor the ears on the knuckle of the Corvette come out further than the Grand Prix so the caliper bracket is significantly shorter then the equivilent F Body caliper/ bracket.

The C5/ GXP calipers share only concept similarities. They are both PBR dual piston calipers. The GXPs are a lighter duty than the C5's. They don't interchange caliper brackets and other than sharing a common rotor size, share no other similarities.

Link

It sounds like the C5 calipers are much better, but can they be put on a Riv?

Well, like with the F-Body brakes, someone will need to try it and find out.

About the extra pedal travel, I've never minded it that much. It just means your foot actually pushes the pedal a 1/4 further to engage the braking action. It happens just as quickly, your reaction doesn't slow down.

And this travel should not be confused with "spongy", which comes from air in the lines and/or OEM rubber hoses. Once you fill the reservoir and the pads start clamping, the pedal gets firm, and the car's gonna stop really quickly.

Does anyone know why the F-Body calipers have such a large reservoir? Did those cars have a different master cylinder?

I'm thinking about the master cylinder myself, but my question is, do 97 and up Rivs with the 11.7 inch rotors have the same master cylinder as lighter w bodies with 10.9 inch rotors? It would explain AA's and RickW's observations vs the observations of the GP crowd if the newer Rivi's have a larger master cylinder (perhaps the same one as the F body?).

teaser pics:

You're gonna be a happy man soon. I still can't believe how good my Riv rides with the new shocks and struts (and handles with the STB's).

ya dude... if i could score some eibachs for 125 buck's id do it prolly