Brake upgrades and wheel fitment
#1
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Joined: Jul 1999
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From: Another world, some other time
Car: 86 LG4 & 92 TBI Firebird
Engine: The Mighty 305!
Transmission: 700R4
Axle/Gears: 3.42
Brake upgrades and wheel fitment
Since there has been alot of different brake upgrades, I have decided to create this thread to list which wheels will fit with which brake upgrades.
If you have upgraded your brakes, please post which brake upgrade you did and which rims (stock or aftermarket) it fit with (or didn't fit).
Please only post wheel fitment info here, not general brake ones.
Thanks!
If you have upgraded your brakes, please post which brake upgrade you did and which rims (stock or aftermarket) it fit with (or didn't fit).
Please only post wheel fitment info here, not general brake ones.
Thanks!
Last edited by Justins86bird; 02-17-2005 at 01:09 AM.
#2
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From: Another world, some other time
Car: 86 LG4 & 92 TBI Firebird
Engine: The Mighty 305!
Transmission: 700R4
Axle/Gears: 3.42
I'll start off.
1LE front brakes fit with stock 15" crosslace Firebird rims
1LE front brakes fit with 17" Ronal R15 Firehawk rims
LS1 rear brakes fit 17" Ronal R15 Firehawk rims
LS1 rear brakes do not fit with stock 15" crosslace Firebird rims
1LE front brakes fit with stock 15" crosslace Firebird rims
1LE front brakes fit with 17" Ronal R15 Firehawk rims
LS1 rear brakes fit 17" Ronal R15 Firehawk rims
LS1 rear brakes do not fit with stock 15" crosslace Firebird rims
Last edited by Justins86bird; 04-05-2006 at 01:31 AM.
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#3
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Joined: Oct 2003
Posts: 278
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From: Northern NV
Car: 1986 Trans Am
Engine: 350 TPI
Transmission: T56
Axle/Gears: 3.27
C5 front brakes will fit under 17" ROH Snypers.
<img src="http://memimage.cardomain.net/member_images/5/web/473000-473999/473585_59_full.jpg">
<img src="http://memimage.cardomain.net/member_images/5/web/473000-473999/473585_59_full.jpg">
Last edited by semiller26; 03-01-2005 at 09:21 PM.
#4
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From: Fort Mill, SC, USA
Car: '88 Iroc, '91 RS, and a '70 RS
Engine: 5.7 TPI; 5.0 TBI; ZZ4/T56 on the ag
Transmission: A4, A4, slated to be a T56
13" C4 HDs fit stock 16" Iroc wheels and 16" stock Z28 alloys and larger wheels;
12.75" C5s fit most 17" and larger wheels, but will NOT fit Torque Thrust IIs without either grinding a bit off the caliper or fitting a small spacer behind the wheel (Contact Chevy Ken for more info);
12" LS1 front brakes fit 16" Iroc and Z28 wheels, and 16" Formula wheels; They'll clear 16" GTA crosslace wheels WITH a spacer between the wheel and hub other wise the caliper will hit the back of the spokes (See LS1 thread in FAQ);
12" C4s will fit most 15" wheels and larger, IE 15" 5 star alloys;
12" 1LEs will fit some 15" wheels and all larger sizes.
Ed
12.75" C5s fit most 17" and larger wheels, but will NOT fit Torque Thrust IIs without either grinding a bit off the caliper or fitting a small spacer behind the wheel (Contact Chevy Ken for more info);
12" LS1 front brakes fit 16" Iroc and Z28 wheels, and 16" Formula wheels; They'll clear 16" GTA crosslace wheels WITH a spacer between the wheel and hub other wise the caliper will hit the back of the spokes (See LS1 thread in FAQ);
12" C4s will fit most 15" wheels and larger, IE 15" 5 star alloys;
12" 1LEs will fit some 15" wheels and all larger sizes.
Ed
Last edited by ebmiller88; 02-23-2005 at 06:59 PM.
#5
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From: Elgin, IL
Car: 1997 Corvette
Engine: LS1
Transmission: 4L60E
Axle/Gears: 2.73 IRS
LS1 rear brakes clear the TA honeycomb-style rims, but with very little clearance between the caliper and inside diameter of rim.
LS1 rear brakes also clear 16x8 4th gen salad shooters (which somewhat makes sense obviously).
I have a pair of IROCs with drag radials in the basement that I'll have to bolt up to check as well.
LS1 rear brakes also clear 16x8 4th gen salad shooters (which somewhat makes sense obviously).
I have a pair of IROCs with drag radials in the basement that I'll have to bolt up to check as well.
#6
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From: Yes I'm Dean
Car: Agood2.8,
Engine: V6rsr,
Transmission: Afrikingoodtime
Here's measurements I calculated and posted in a post on 9/8/04 showing the different offsets with various brake kits. This info will help with any change of total offset of the wheel and brake assembly.
["I have some confirmed offset figures for scrub radius between the different brake setups. All figures are measured with a factory 16" "Fronts" Iroc rim with the standard offset of 0mm.
Measured from the spindle mount hole for the 1LE bracket going outward.
----------------------------
Standard Non-1LE front -small bearings(10.5" rotor)
3.630"
1LE brake setup- large bearings (12" rotor)
*THIS IS THE FACTORY STANDARD FOR 245/50-16 tires on an 8"wide rim*
3.948" [+.318 offset, or just over 5/16"]
My setup-large bearings (12.9" rotor) with a 3/16" wheel spacer for rim to caliper clearence
3.967" [+ .337" offset, or just over 5/16"}
13" C4 HD's on 1LE hub-large bearings(13" rotor)
4.248" [+.618" offset, or just shy of 5/8"]
13" C4 HD's on std hub-small bearings(13"rotor)
3.930" [+.300" offset, or just shy of 5/16"]
C5 setup on stand or 1LE hubs (12.75" rotor)
No clue?If anyone has a "+ or - "offset from any of the combo's above- please contribute."]
["I have some confirmed offset figures for scrub radius between the different brake setups. All figures are measured with a factory 16" "Fronts" Iroc rim with the standard offset of 0mm.
Measured from the spindle mount hole for the 1LE bracket going outward.
----------------------------
Standard Non-1LE front -small bearings(10.5" rotor)
3.630"
1LE brake setup- large bearings (12" rotor)
*THIS IS THE FACTORY STANDARD FOR 245/50-16 tires on an 8"wide rim*
3.948" [+.318 offset, or just over 5/16"]
My setup-large bearings (12.9" rotor) with a 3/16" wheel spacer for rim to caliper clearence
3.967" [+ .337" offset, or just over 5/16"}
13" C4 HD's on 1LE hub-large bearings(13" rotor)
4.248" [+.618" offset, or just shy of 5/8"]
13" C4 HD's on std hub-small bearings(13"rotor)
3.930" [+.300" offset, or just shy of 5/16"]
C5 setup on stand or 1LE hubs (12.75" rotor)
No clue?If anyone has a "+ or - "offset from any of the combo's above- please contribute."]
Last edited by RTFC; 02-27-2005 at 01:03 PM.
#7
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Joined: Jan 2005
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From: Amsterdam , NY
Car: 1985 Trans Am
Engine: vee eight
Transmission: auto
Axle/Gears: 4.10 gears
c5s will not fit 18 inch boyd coddington smoothies, they look like tt2's . The caliper either has to be ground like chevyken did or do like i did and use a 5/16 inch spacer, but i think 1/2 woulda worked but never found a half inch spacer.
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#8
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Joined: Jul 1999
Posts: 2,754
Likes: 7
From: Ahead of you...
Car: 1984 LG4 Camaro
Engine: 350 Roller Motor
Transmission: Level 10 700R4
Axle/Gears: Strange 12 bolt 3.42
Does anyone know if the Ronal 17" Firehawks will clear the Baer 13" Track system. Also if the 10 spoke 2000+ 17" Camaro wheels?
Thanks in advance
Thanks in advance
#9
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From: Fort Mill, SC, USA
Car: '88 Iroc, '91 RS, and a '70 RS
Engine: 5.7 TPI; 5.0 TBI; ZZ4/T56 on the ag
Transmission: A4, A4, slated to be a T56
They should clear both but no problems with the 4th gen wheels, I'm sure of that. It will depend on the backspacing on the Ronals.
Ed
Ed
#10
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From: Elgin, IL
Car: 1997 Corvette
Engine: LS1
Transmission: 4L60E
Axle/Gears: 2.73 IRS
Got a chance to get out on my car to do some work today. Update to LS1 rear brakes.
The older IROC 16x8 wheels fit without a problem. They have a decent amount of room behind them actually. Quite a bit more than my honeycomb TA style ones had.
The 15x4" donut spare tire will NOT fit, and neither will the N64 aluminum space-saver spare tire. They'd require a decent sized spacer to be run with the LS1 rears.
Oh, and the 18x9.5" vette wheels fit without a problem, but I think most people know that'd work
The older IROC 16x8 wheels fit without a problem. They have a decent amount of room behind them actually. Quite a bit more than my honeycomb TA style ones had.
The 15x4" donut spare tire will NOT fit, and neither will the N64 aluminum space-saver spare tire. They'd require a decent sized spacer to be run with the LS1 rears.
Oh, and the 18x9.5" vette wheels fit without a problem, but I think most people know that'd work
#11
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Joined: May 2002
Posts: 678
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From: Gloucester,England,UK
Car: '92 RS Camaro
Engine: 406ci D1SC SBC
Transmission: TH400
Axle/Gears: 9" W/Truetrac
When I get some new wheels,I was thinking of getting 4th gen pattern ones and use adapters.I was thinking this would give me the extra clearance to fit the wide porsche calipers I have.Does this sound like a good idea?Because of where I live,it's not easy to get my hands on a wheel to try the spacing.I was thinking of using 17" Boyd Hotrod wheels.Has anyone else got experience of these wheels and big calipers?
#12
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iTrader: (1)
Joined: Jan 2000
Posts: 640
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From: Clifton, NJ
Car: '88 Formula
Engine: 350 TPI
Transmission: T-5... in need of slight rebuild
Does anyone know if the C4 HD kit would work under a set of SLP ZR1 replica wheels? The diameter of the rim at the mounting pad is 14.75" and opens up to 16.75" at the inside lip. Thanks.
http://www.slponline.com/view_product.asp?P=81000
http://www.slponline.com/view_product.asp?P=81000
#13
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Joined: Aug 2004
Posts: 4,168
Likes: 2
From: Marietta, GA
Car: '91 Firebird Convertible
Engine: 305 TBI (LO3)
Transmission: 700r4, Vette Servo
Axle/Gears: 3.27 9 Bolt, PBR disks
I'm really interested in the content of this thread but here is my perspective. I have a totally stock braking system that I am not happy with. I definitely want an upgrade.
Where do I start? What are the costs and what should I expect to pay for new components?
Knowing the fitment is certainly key...
Where do I start? What are the costs and what should I expect to pay for new components?
Knowing the fitment is certainly key...
#14
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Joined: Jun 2000
Posts: 1,536
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From: Naperville, IL
Car: 89 Iroc Hardtop
Engine: LB9 w/G92 Pkg
Transmission: T5 5-Speed
Axle/Gears: 9-Bolt, 3.45
Now that I have a C4HD kit on the way, I'm looking for some new 17" wheels. Since this kit moves the wheels out almost 5/8" per side, I want opinions as to what backspacing I would need for a 17x8" wheel.
Math owns me.
Math owns me.
#15
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Joined: Aug 2004
Posts: 4,168
Likes: 2
From: Marietta, GA
Car: '91 Firebird Convertible
Engine: 305 TBI (LO3)
Transmission: 700r4, Vette Servo
Axle/Gears: 3.27 9 Bolt, PBR disks
Originally posted by Firebird 383
Math owns me.
Math owns me.
(and I still need a brake upgrade --but this time with GTA's to consider)
#16
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Joined: Jul 2003
Posts: 1,104
Likes: 1
From: Pensacola, FL
Car: 1999 Saturn SL2
Engine: 4 cylinder
Transmission: 4-speed automatic
Originally posted by Justins86bird
I'll start off.
1LE front brakes fit with stock 15" crosslace Firebird rims
1LE front brakes fit with 17" Ronal R15 Firehawk rims
I'll start off.
1LE front brakes fit with stock 15" crosslace Firebird rims
1LE front brakes fit with 17" Ronal R15 Firehawk rims
I am interested in upgrading my brakes very soon and 1LE seems like it might be a good investment. I do not want to change the stock wheels.
#18
Member
Joined: May 2002
Posts: 206
Likes: 0
From: Elk Grove, CA
Car: 1988 Pontiac Trans-AM
Engine: TPI 350 (5.7L)
Transmission: 700R4
What are the "1LE" front brakes. What car were they origanly used on or is it a company.
Can you tell I know diddle about brakes?
Buy the way im running the GTA rims in black.
Can you tell I know diddle about brakes?
Buy the way im running the GTA rims in black.
#19
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Joined: Aug 2004
Posts: 4,168
Likes: 2
From: Marietta, GA
Car: '91 Firebird Convertible
Engine: 305 TBI (LO3)
Transmission: 700r4, Vette Servo
Axle/Gears: 3.27 9 Bolt, PBR disks
I've been watching this thread for a long time now. Getting details is like pulling teeth but I suspect if we do a search for a long enough time, all will be made clear.
Call me lazy.
Call me lazy.
#20
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Posts: 3,109
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From: Tacoma, Wa
Car: '91 TA vert
Engine: turboLSx
Transmission: T56
Axle/Gears: 3.23
Originally posted by ebmiller88
12" LS1 front brakes fit 16" Iroc and Z28 wheels, and 16" Formula wheels; They'll clear 16" GTA crosslace wheels WITH a spacer between the wheel and hub other wise the caliper will hit the back of the spokes (See LS1 thread in FAQ)
12" LS1 front brakes fit 16" Iroc and Z28 wheels, and 16" Formula wheels; They'll clear 16" GTA crosslace wheels WITH a spacer between the wheel and hub other wise the caliper will hit the back of the spokes (See LS1 thread in FAQ)
#21
Wondering if 18"x9,5" Vette C6 Z06 wheels (et 50)(with 2" adapters of course) will clear Wilwood 13" frontbrakes (sold on hawks, Thunderracing etc.)
also wondering how wide you can go with these rims before rub, ? 265-tires? 275?...
also wondering how wide you can go with these rims before rub, ? 265-tires? 275?...
Last edited by Affe; 11-26-2005 at 07:35 AM.
#22
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From: Tacoma, Wa
Car: '91 TA vert
Engine: turboLSx
Transmission: T56
Axle/Gears: 3.23
Originally posted by Nate86
Are you referring to the 20-slot concave wheels or were there some other 15" wheels that came on the Firebirds?
I am interested in upgrading my brakes very soon and 1LE seems like it might be a good investment. I do not want to change the stock wheels.
Are you referring to the 20-slot concave wheels or were there some other 15" wheels that came on the Firebirds?
I am interested in upgrading my brakes very soon and 1LE seems like it might be a good investment. I do not want to change the stock wheels.
#25
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From: Tacoma, Wa
Car: '91 TA vert
Engine: turboLSx
Transmission: T56
Axle/Gears: 3.23
Originally posted by iansane
Does this apply to the c5 calipers? My car came stock with the slip on spacer on the drum rear (which I actually saved when I swapped rears for discs.) Would that slipon be enough of a spacer?
Does this apply to the c5 calipers? My car came stock with the slip on spacer on the drum rear (which I actually saved when I swapped rears for discs.) Would that slipon be enough of a spacer?
Originally posted by ebmiller
A C5 setup won't fit GTA wheels, it's just too big. It's the combination of the rotor and caliper. A LS1 setup does fit by using the spacer you mentioned (yes, rear drum spacer) to get the caliper to clear the spokes. Otherwise, the caliper hits the spokes
A C5 setup won't fit GTA wheels, it's just too big. It's the combination of the rotor and caliper. A LS1 setup does fit by using the spacer you mentioned (yes, rear drum spacer) to get the caliper to clear the spokes. Otherwise, the caliper hits the spokes
#26
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Joined: Jan 2006
Posts: 43
Likes: 0
From: NY
Car: 1991 Z28
Engine: LB9
Transmission: terrible700r4
how big of a spacer are we talking about for C5 brakes to fit a torque thrust II 17x8 with 4inchs backspacing and -11.43mm? or would the same rim 17x8 with 4.75inchs backspacing and 7.62mm offset fit better?
Last edited by mpsoldier; 01-29-2006 at 08:38 PM.
#27
I want to save this info here - hopefully this part 2 won't get erased like a mod deleted part on on the suspension board. I will redo part one later.
------
part 2
Diameter does not change offset, width does.
So with the above figures on those perticular brake mounting surfaces and 8" wide rims, you should be able to simply add the width of the rim to the backside and subtract half the new rim width difference to the offset to match the same outer tire edge overall.
example- 8" to a 9" is 1 inch difference on the inner wall of the rim so half that difference is .5" or 13mm. Since the new rim is wider, the center line of the rim changes so a new offset calculation is needed.
We now start with a 9"rim that has a centerline (o offset) +.5" or +13mm inward from the 8" rim. Subtract the difference.
+5mm subtract +13mm = -8mm offset
So a 9" rim on Standard brakes would need a -8mm offset for maximum turning radius clearance without hitting the fender in suspension travel.
From what I have measured on my car and being so lowered, I would never go larger than a 9" wide rim and a 10.2" tire up front.
------
part 2
Diameter does not change offset, width does.
So with the above figures on those perticular brake mounting surfaces and 8" wide rims, you should be able to simply add the width of the rim to the backside and subtract half the new rim width difference to the offset to match the same outer tire edge overall.
example- 8" to a 9" is 1 inch difference on the inner wall of the rim so half that difference is .5" or 13mm. Since the new rim is wider, the center line of the rim changes so a new offset calculation is needed.
We now start with a 9"rim that has a centerline (o offset) +.5" or +13mm inward from the 8" rim. Subtract the difference.
+5mm subtract +13mm = -8mm offset
So a 9" rim on Standard brakes would need a -8mm offset for maximum turning radius clearance without hitting the fender in suspension travel.
From what I have measured on my car and being so lowered, I would never go larger than a 9" wide rim and a 10.2" tire up front.
#28
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From: Carrollton, TX, USA
Car: 1992 Chevy Camaro RS
Engine: 305 TBI
Transmission: T-56
Not sure if this has been addressed...didnt bother reading the rest of the post but:
C5 brake upgrades with 1LE hubs
1.5" spacers
AFS 17x9.5 Z06 replica wheels (56mm - I think - offset)
Wheels fit perfectly. They tuck in pretty nice....and the only problem I had was slight grinding on the driver side wheel weight...just had to grind down the tie rod a bit. I think I may have actually grinded a little too much...but we'll see...I'll watch it and make sure I dont see any cracks forming or anything.....or probably just replace it and grind a little less off.
C5 brake upgrades with 1LE hubs
1.5" spacers
AFS 17x9.5 Z06 replica wheels (56mm - I think - offset)
Wheels fit perfectly. They tuck in pretty nice....and the only problem I had was slight grinding on the driver side wheel weight...just had to grind down the tie rod a bit. I think I may have actually grinded a little too much...but we'll see...I'll watch it and make sure I dont see any cracks forming or anything.....or probably just replace it and grind a little less off.
#29
Junior Member
Joined: Feb 2006
Posts: 3
Likes: 0
From: Vienna, Virginia
Car: 1986 IROC-Z28; 1983 Trans Am; 1995 Trans Am; 1985 Fiero GT
Engine: 5.8L/353; 5.0/305; 5.7/350; 2.8/173
Transmission: A/T; A/T; M6; M4
Axle/Gears: 3.73; 3.08; 3.73; 3.65
Could LT1 brakes be used? Im upgrading my 1995 Trans Am to a Baer Track Kit and was wondering if I could use the LT1 rotors and calipers as a slight upgrade for my 1983 Trans Am, since I've got them lying around.
#30
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iTrader: (4)
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Posts: 900
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From: N. CA
Car: '85 TA
Engine: Aluminum Fuelie
Transmission: Mother of All Manuals
Worksheet
I've made up a chart with the brake data from this thread. I'll be searching through the forums as I have time and collect more data, but so far, I think it will be a benefit to those who are looking at wheel and brake upgrades.
I'm thinking of getting rid of the "Most 15/16/17/18" and larger" section, but let me know your thoughts.
Last updated: 4/5/07
I'm thinking of getting rid of the "Most 15/16/17/18" and larger" section, but let me know your thoughts.
Last updated: 4/5/07
Last edited by super_kev; 04-05-2007 at 05:40 AM.
#31
Thread Starter
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Joined: Jul 1999
Posts: 3,838
Likes: 4
From: Another world, some other time
Car: 86 LG4 & 92 TBI Firebird
Engine: The Mighty 305!
Transmission: 700R4
Axle/Gears: 3.42
Originally Posted by Nate86
Are you referring to the 20-slot concave wheels or were there some other 15" wheels that came on the Firebirds?
I am interested in upgrading my brakes very soon and 1LE seems like it might be a good investment. I do not want to change the stock wheels.
I am interested in upgrading my brakes very soon and 1LE seems like it might be a good investment. I do not want to change the stock wheels.
#33
Senior Member
Joined: Sep 2004
Posts: 878
Likes: 1
Car: 89' Iroc-Z G92
Engine: TPI 305 G92
Transmission: T-5
Axle/Gears: Limited 9 bolt, 3.45
Does anyone have the complete measurements for the 88-89 Stock Double Stripe Iroc Wheel..
oh some specs for C6 Z06 brakes...
Whats the RIM ID gap? he measured with the stock Z06 wheel.
oh some specs for C6 Z06 brakes...
Originally Posted by Norty @ Corvette Forum
I just measured the centerline to outer most edge of the caliper: 8.00" exactly! The caliper outer edge to rim ID gap with OEM wheels is 5/16ths". Don't forget the tape-on wheel weights will make this gap even smaller.
#34
Junior Member
Joined: Feb 2006
Posts: 66
Likes: 0
From: w. jordan utah
Car: 86 Z-28
Engine: 350
Transmission: 700-r4
will they fit
i have an 86 Z-28 with stock 4-wheel disc's i am thinking of getting all new roters drilled and slotted. now the question i have a brand new set of a.r. 15 by 7 tourque thrust-d's will these work with no problem? i plan to run 245 60 15s. i just don't like the look of the stock wheels that came on the car. any help? tom
#35
Senior Member
Joined: Sep 2004
Posts: 878
Likes: 1
Car: 89' Iroc-Z G92
Engine: TPI 305 G92
Transmission: T-5
Axle/Gears: Limited 9 bolt, 3.45
Originally Posted by surfertom
i have an 86 Z-28 with stock 4-wheel disc's i am thinking of getting all new roters drilled and slotted. now the question i have a brand new set of a.r. 15 by 7 tourque thrust-d's will these work with no problem? i plan to run 245 60 15s. i just don't like the look of the stock wheels that came on the car. any help? tom
Those should fit just fine.. try to get blank rotors or just slotted, drilled rotors crack and warp easily...
#36
Junior Member
Joined: Mar 2004
Posts: 48
Likes: 0
From: Talent Oregon
Car: 1988 IROC-Z
Engine: e-tec headed ZZ-4 350
Transmission: t56
Axle/Gears: 9 bolt 3.7 posi
ROH ZS wheels and C5 front brakes
Is anyone running c-5 front brakes with ROH 17x9.5 Wheels? Who thinks they will fit, I have the wheels and these are the brakes I would like to run possible.
Thanks guys
Thanks guys
#37
Aftermarket wheels with C4 upgrade
I have the Ed Miller C4 brake upgrade on the front of my 1988 IROC. This caused the surface of the hubs to move outward some 5/8 to 3/4 inches. Consequently the stock front IROC wheels did not fit in the wheel well, they hit the fender lip. The stock rear IROC wheels fit but, the inside of the spokes hit the caliper so I had to add a spacer (Mr. Gasket 7/32-inch gives me about a 1/32 to 1/16-inch clearance between spokes and caliper). My question is, what do I get for backspacing and offset on aftermarket wheels? I would like to go with 17-inch by 8-inch on the front. The stock wheel has a 5-inch backspacing with a 16 mm positive offset. Do I simply subtract the 5.5 mm of the spacer from the 16 mm offset? I am concerned because I will have to order rims and with special offsets, I have one chance.
Another question about the rears. I have the Ed Miller PBR upgrade and currently have the stock front IROC wheels on the back which seem to fit fine. If I go with 17 X 9 on the rear, should I simply increase the back spacing by 0.5-inches (with zero offset) which would be 4.85-inches (4.35 + 0.5)?
Thanks for any help!
Another question about the rears. I have the Ed Miller PBR upgrade and currently have the stock front IROC wheels on the back which seem to fit fine. If I go with 17 X 9 on the rear, should I simply increase the back spacing by 0.5-inches (with zero offset) which would be 4.85-inches (4.35 + 0.5)?
Thanks for any help!
Last edited by Kurt88IROC; 04-12-2006 at 10:53 AM.
#39
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Joined: Aug 2001
Posts: 2,136
Likes: 1
From: Costal Alabama
Car: 1989 Iroc-Z
Engine: 350, ZZ4 equivalent
Transmission: Pro-Built Road Race 700R4
Axle/Gears: 3.23 Dana 44
Just a heads up to everyone, I have written up a how-to article on front brake upgrades, visit www.LukeSkaff.com. The article has been up for a few months but have been so busy lately I forgot to even tell anyone about it.
#40
Member
Joined: Dec 2001
Posts: 471
Likes: 0
From: Burnaby, BC, Canada
Car: 1989 Camaro Iroc-Z
Engine: 305 TPI (LB9)
Transmission: Auto 4
So if I get this correctly, since nobody actually said yah or nah to this. C5 will not fit under a stock 16x8 IROC rim? What about the HD? (I think I've seen the answer to this somewhere, but searching got me nowhere)
#43
Front Brake upgrades
I have a 1985 IROC Camaro, and I am looking to upgrade the front disc brakes from the original discs and rotors. I was wondering if the current spindles can support 12 inch rotors. If not, is it possible to interchange the spindle/strut assembly from a newer Camaro or Trans Am to use its bigger rotor/caliper assembly?
#44
Member
Joined: Jan 2006
Posts: 161
Likes: 0
From: Camp Lejeune, NC
Car: 83' Camaro
Engine: 355
Transmission: TH-350
Axle/Gears: Open...
Originally Posted by Brothaman
I have a 1985 IROC Camaro, and I am looking to upgrade the front disc brakes from the original discs and rotors. I was wondering if the current spindles can support 12 inch rotors. If not, is it possible to interchange the spindle/strut assembly from a newer Camaro or Trans Am to use its bigger rotor/caliper assembly?
#45
Supreme Member
iTrader: (7)
Joined: Mar 2001
Posts: 6,420
Likes: 5
From: Fort Mill, SC, USA
Car: '88 Iroc, '91 RS, and a '70 RS
Engine: 5.7 TPI; 5.0 TBI; ZZ4/T56 on the ag
Transmission: A4, A4, slated to be a T56
Originally Posted by waltersb
So if I get this correctly, since nobody actually said yah or nah to this. C5 will not fit under a stock 16x8 IROC rim? What about the HD? (I think I've seen the answer to this somewhere, but searching got me nowhere)
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Originally Posted by pawcio
I am wondering if C4 Heavy Duty calipers (13"rotors) will fit GTA 16" wheels?
anyone know?
anyone know?
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Originally Posted by Brothaman
I have a 1985 IROC Camaro, and I am looking to upgrade the front disc brakes from the original discs and rotors. I was wondering if the current spindles can support 12 inch rotors. If not, is it possible to interchange the spindle/strut assembly from a newer Camaro or Trans Am to use its bigger rotor/caliper assembly?
Ed
Last edited by ebmiller88; 05-24-2006 at 07:13 AM. Reason: Automerged Doublepost
#47
spacing
Your wheels must be at least 4" larger than your disc brakes, generally. But, I don't know anything about backspacing, or how to prevent the "spokes" from rubbing the calipers. Probably install a spacer between the brake disc and the wheel.
#48
Member
Joined: May 2005
Posts: 107
Likes: 0
From: Goose Creek, SC
Car: 87 Trans Am
Engine: 434 being built
Transmission: 700R4
Axle/Gears: 3:73
I'm getting ready to order a custom sized wheel from covington. What size would you recommend? Please see my new thread. Thanks
#50
TGO Supporter
Joined: Sep 2000
Posts: 6,775
Likes: 26
From: So.west IN
Car: 87 Formula/ 00 Xtreme
Engine: TPI 305/ v6
Transmission: struggling t-5/ 4l60E
Axle/Gears: 3.08/ 3.23
Re: Brake upgrades and wheel fitment
I did not see it addressed in this post so I would like to add:
'LS1' 12" front brakes will clear Ronal R-15 (Firehawk) wheels (.... thankfully).
'LS1' 12" front brakes will clear Ronal R-15 (Firehawk) wheels (.... thankfully).