Swapping brakes, tools, tips, and tricks?

[Payne]

Howdy all.

New viper owner here, just picked up a beautiful Roe'd 98 GTS, coming from a fully prepped road race z06.

The viper brakes are non up to *****, so I found a set of wilwoods that I am going to swap tuesday night. IE drive my viper to him, pull my stock brakes, put them on his car, put his wilwoods on my car.

A few questions:

1) Do the OEM rotors have locking phillips head bolts in them?
2) What is the size of the bolts that hold on the calipers? What is the torque spec on them?
3) I assume the wheels are 3/4" lugs, correct?
4) What size is the hardline to softline fitting for the brake lines?
5) Any tips and tricks to bleeding out the system after changing all 4 brake lines?
6) Anything special about bleeding a wilwood caliper?
7) (stupid question) any tips or trick for lifting and jackstanding a viper? We are going to jackstand both cars and do the swap across
8) (really stupid question) Is the viper metric or standard?

I assume its a pretty straightforward job. Get wheels off, 4 lines to get the brakes off, 2 caliper bolts a wheel, and a deadblow to pull the rotors off. Swap parts, reassemble with locktite, and bleed well (RR, LR, RF, LF)? Anything I am missing?

Thanks in advance!

Jason

 

[Catwood]

Your brakes are fine. I out brake Z06s at the track all the time.....

 

[dave6666]

Your brakes are fine. I out brake Z06s at the track all the time.....

But his fully road race prepped Z06 may not have had stock brakes...

 

[Catwood]

Define "Road Race Prepped"

 

[dave6666]

Define "Road Race Prepped"

Radio delete?

 

[Catwood]

I figured it was to turn off the traction control.....

 

[Payne]

I figured it was to turn off the traction control.....

LOL. I know most vette owners are **********, but there are some of us that know our ****.

Its on coilovers, all bushings are poly, cornerweighted, and a lot of seat time to dial it in.

Plus all the heat goodies: big radiator, oil cooler, brake ducts, etc... Car also has 489rwhp and 630rwhp on the bottle. Has humbled a lot of vipers in its day.

I'm still on stock rotors, as I autoX the car a lot on 17" wheels, but I am on SS lines, Motul, Carbotech XP pads, etc...

The big drawback of the GTS so far is there's no proportioning valve, and the fronts always lock first (by design).

If you are outbraking z06 owners on the track, its definitely a driver comparison. Any way you slice it, running 38mm single piston rears that make up no more than 15% (so I've read) clamping force in a heavier car without ABS is not going to outbrake a z06.

Anyway, I went to the viper to return to a more streetable car, as I'm now unable to track anything regularly.

I now know the caliper mounts are 18mm and need 85ft-lbs. I just need to know the brake line size and should be all set

JP

 

[cyaford]

Your brakes are fine. I out brake Z06s at the track all the time.....

No way my '97 GTS will out brake my old '02 Z06, stock for stock.

 

[Catwood]

No way my '97 GTS will out brake my old '02 Z06, stock for stock.

'
OK...first I cheat a little. I run Toms 40 MM on the rear and Dave's prop valve to dial it in. It is an OEM part though so who cares.

the rest of my brake upgrades are to keep them reliable as heat builds.

race pads, air deflectors and SST llines.

I took a guy in my Viper that was tracking a Z06..the ones with 385 HP (01?) Anyway, scared the crap out of the guy going in as deep as I did. I always have to check up when I'm behind one going into certian turns as being in HPDE, bumping would be a real bad move. I know I'm over a G in brake force. I'd have to go revisit the data to confirm an actual number.

But for street use, brakes are fine, for autocross...probably still fine...for the track...it's still probably ok but could be tweeked a little.

YMMV

 

[Dave's Big Brakes]

Ok, which Wilwoods? how many pistons? what are piston sizes? Torque/HP?


You'll need an adjustable pro valve kit to fine tune distribution block ****'s

You'll be doing a little cutting on the rear mounting tabs If the other car has wilwoods on the rears it's not a straight swap out.

Big Brake Dave
Dave's Big Brakes

 

[Catwood]

OK...Dave's got some great stuff and great deals. You can get most, if not everything, you need from him. We need to keep the old guys happy.

 

[Payne]

'
OK...first I cheat a little. I run Toms 40 MM on the rear and Dave's prop valve to dial it in. It is an OEM part though so who cares.

the rest of my brake upgrades are to keep them reliable as heat builds.

race pads, air deflectors and SST llines.

I took a guy in my Viper that was tracking a Z06..the ones with 385 HP (01?) Anyway, scared the crap out of the guy going in as deep as I did. I always have to check up when I'm behind one going into certian turns as being in HPDE, bumping would be a real bad move. I know I'm over a G in brake force. I'd have to go revisit the data to confirm an actual number.

But for street use, brakes are fine, for autocross...probably still fine...for the track...it's still probably ok but could be tweeked a little.

YMMV

40mm rear brakes and Race pads does not equal stock

I was going to go with Dave's but then I came up on a killer deal on wheels, tires, and brakes from a guy going back to stock, that I couldnt pass up. Otherwise I'd already have bought the rear upgrade and gone that way.

AutoX will definitely need at least the 40mm rear brakes.

Ok, which Wilwoods? how many pistons? what are piston sizes? Torque/HP?


You'll need an adjustable pro valve kit to fine tune distribution block ****'s

You'll be doing a little cutting on the rear mounting tabs If the other car has wilwoods on the rears it's not a straight swap out.

Big Brake Dave
Dave's Big Brakes

Its a 6 piston front, GNIII and 4 piston rear I think.

I'll probably look to you for the adjustable pro next week.

How hard are the tabs to grind off? I'm not sure if I'll have air where I am. Will I need a serious grinder, or could I do with a 18V DeWalt?

JP

 

[Dave's Big Brakes]

Hey JP,

I use a sawsall with a 9" blade from Home Depot but a cutoff wheel works ok also.
Are you swapping spindles with him also, then you wouldn't have to do any cutting. If not then he'll have a problem installing your old rear calipers, as the mounting tabs will be gone. You need to ck that before you do anything.
GN3's up front & probaly superlite 2 or Dynolite 2 on the rears sound about right.

Big Brake Dave

 

[Payne]

Hey JP,

I use a sawsall with a 9" blade from Home Depot but a cutoff wheel works ok also.
Are you swapping spindles with him also, then you wouldn't have to do any cutting. If not then he'll have a problem installing your old rear calipers, as the mounting tabs will be gone. You need to ck that before you do anything.
GN3's up front & probaly superlite 2 or Dynolite 2 on the rears sound about right.

Big Brake Dave

Dave, how hard is it to swap spindles w/o a compressor? Any idea what tools it takes? I'm gonna be doing it on my back and would like to be as prepared as possible.

Also, do you sell Wilwood pads?

Jason

 

[Catwood]

40mm rear brakes and Race pads does not equal stock

JP

Technically it does according to the Viperdays rule book. It is the same caliper, just a bored out piston.

 

[Tom F&L GoR]

Yes, as determined by Tom Sessions for Viper Days, the 40mm rear caliper is a "safety" upgrade and does not add points. Since it's based on the OEM body, nothing on the knuckle is modified and you re-use your current pads, rotors, hoses, wheels, etc. PM me for details - I have some data sheets and other information I can email you (so include your email address, please.)

Uh... bored out caliper and sleeved piston - same as well-done auto restoration work.

 

[Payne]

Got the swap done last night. Wilwoods are awesome and HREs are dead ****.

Rear caliper: 15mm bolt at the bottom and 6mm alen key on top
Front caliper: two 18mm bolts
Brake lines: 3/8"
Bleeders: 7/16"

 

[jcaspar1]

Tom,
Did you ever come up with a rear upgrade that worked well with the StopTech front setup? I remember you working on it a while ago.

 

[Tom F&L GoR]

Yes, Joseph Dell did this.

The background is that the StopTech front only kit uses a caliper with SMALLER pistons and a larger diameter front rotor. That causes you to push harder on the pedal, getting more rear braking, but because the fronts are smaller, they don't lock up. The result is better balance.

The concern was that with smaller front pistons and also larger 40mm rear pistons the balance would be too far rearward and cause rear lock up. With credit to StopTech, I modified their graph to show where I believe the small front/large rear would end up.

Based on the math and also Joseph's good results, the combination is a good one. I would want to revisit the math to evaluate a StopTech front caliper using the OEM diameter rotor, which would be another baby step to the right.

The reason the StopTech kit and the 38mm rear caliper fall on top of each other is that the 38mm rear caliper has (mathematically) the identical front-rear piston size balance. In fact, that is how the original "larger" rear calipers were developed - to match the StopTech peformance. (Smaller fronts + OEM rear = OEM front + 38mm rear.) The ABS data point is if the proportioning valve and/or ABS was not working. There were some forum comments where people with an '01 ABS car disabled the system and found borderline rear lockup. Any four piston caliper on the rear will be way off the right. However, the proportioning valve reduces brake line pressure to bring the front-rear balance back to the middle.

 

[ILLSMOQ]

Has humbled a lot of vipers in its day.

humbled a lot of Vipers eh? I do recall a video was shot one night....but oddly enough, it never surfaced.....

good move on the GTS btw

 

[BLWNGTS]

Has humbled a lot of vipers in its day.

?!?! Really?!

I recall a certain Blue with White stripe Gen 2 with a license plate that read BLWN GTS humble a certain z06 built with No2!! I also recall that certain viper owner not wanting to race but then got tired of all the vette guys talkin crap! I then recall pullin away like a madman, spinning the tires on the freeway, as there was video proof of it..... not once but twice!! When we were all in Mexico of course... Then I recall asking that zo6 guy for a copy of the tape for over a year but never getting it!!

Hahaha... whats up Payne! just a little **** talkin for a new member that has come to the darkside!! Congrats on the choice man! You gotta bring it by Santana Row on Saturday and show it off!!

That is the exact reason I sold my Gen 2... the brakes are horrible and I had mine upgraded with rotors and pads....

OHHHH... AND I STILL WANT A COPY OF THE VIDEO!!!

 

[MikeR]

Hey Payne,

Yea , I still remember the night we raced you on hwy 237. We never got a chance to beat up on you with our superchargers.

Anyways, so did you get Peters old Viper?
You'll have to stop by Santana Row sometime, show off your Viper at one of our meets on saturday mornings.

 

[grcforce327]

Hey Payne,

Yea , I still remember the night we raced you on hwy 237. We never got a chance to beat up on you with our superchargers.

No street racing allowed on the VCA!!!
It's called spirited driving!

 

[ILLSMOQ]

Hey Payne,

Yea , I still remember the night we raced you on hwy 237.

...237 in Mexico yeah?

 

[BLWNGTS]

...237 in Mexico yeah?

Thats the one!!! man... that was a long drive that night!!

 

[MikeR]

Thats the one!!! man... that was a long drive that night!!

Yep, good ole hwy 237, goes through guadalajara to Michuacan,. Not many people know of that road, may not even show up on the maps.

We would never street race in the USA, thats Illegal. Ask Jon.............

 

[ILLSMOQ]

hahahaa...yeah Jon knows

 

[Payne]

?!?! Really?!

I recall a certain Blue with White stripe Gen 2 with a license plate that read BLWN GTS humble a certain z06 built with No2!! I also recall that certain viper owner not wanting to race but then got tired of all the vette guys talkin crap! I then recall pullin away like a madman, spinning the tires on the freeway, as there was video proof of it..... not once but twice!! When we were all in Mexico of course... Then I recall asking that zo6 guy for a copy of the tape for over a year but never getting it!!

Hahaha... whats up Payne! just a little **** talkin for a new member that has come to the darkside!! Congrats on the choice man! You gotta bring it by Santana Row on Saturday and show it off!!

That is the exact reason I sold my Gen 2... the brakes are horrible and I had mine upgraded with rotors and pads....

OHHHH... AND I STILL WANT A COPY OF THE VIDEO!!!

I still got the video, and I still got the z06. You know, on video, your headlights look pretty spiffy. behind me. Thanks for the race, the girl sitting shotgun was pretty ... excited. Either the car or video are available to prove themselves.

Yeah, I bought Peter's viper. The car is unbelievably clean. It now has 20 pistons of brakes, and HREs

 

[Payne]

...237 in Mexico yeah?

Curtis, right? How you been dude? Hows the Gen III treating you?

 

[ILLSMOQ]

Curtis, right? How you been dude? Hows the Gen III treating you?

Gen III is still doing it....with the cooler weather coming we should go out and see how these cars stack up.

how did you like autocrossing the viper vs the vette??...torque, 3.07's and taller tires make for a different experience eh?


Hey Stevo...where did Peter get that Roe blower from??? small world huh?