Pontiac - Street No question too basic here!

          
Reply
 
Thread Tools Display Modes
  #1  
Old 04-27-2023, 10:00 AM
ScottP's Avatar
ScottP ScottP is offline
Senior Member
 
Join Date: May 2007
Location: Tewksbury, MA
Posts: 128
Default Project: Big brakes for a big car

I kicked off a project this past winter that I'm just wrapping up now, and thought
folks here might enjoy seeing it. My '70 Bonneville was an original front-wheel
disc car from the factory, and I updated the rears to discs many years ago. I'm
running the 17x8" version of the Year One aluminum Rally IIs and have wanted
to install bigger front brakes ever since the new wheels went on. I finally got
around to putting the pieces together to make it happen.

What you see are 330mm x 32mm thick rotors from a mid 2000's Mercedes AMG
along with matching Brembo 4-piston calipers. These were the biggest I could
manage to squeeze under the 17" wheels.

I'm just getting everything buttoned up and bled now. Might be able to go for
a ride this weekend if the weather cooperates. I've attached a few pics showing
the setup.
Attached Thumbnails
Click image for larger version

Name:	IMG_2051.jpg
Views:	90
Size:	55.8 KB
ID:	611573   Click image for larger version

Name:	IMG_2068.jpg
Views:	87
Size:	53.7 KB
ID:	611575   Click image for larger version

Name:	IMG_2069.jpg
Views:	109
Size:	52.8 KB
ID:	611576   Click image for larger version

Name:	IMG_2070.jpg
Views:	103
Size:	59.9 KB
ID:	611577   Click image for larger version

Name:	IMG_2074.jpg
Views:	81
Size:	39.4 KB
ID:	611578  


__________________
70 Bonneville convertible, Vortech V7 YSi supercharged EFI455 + 4L80E
The Following User Says Thank You to ScottP For This Useful Post:
  #2  
Old 04-27-2023, 10:04 AM
Tarl Tarl is offline
Senior Member
 
Join Date: Apr 2001
Location: Boston, MA
Posts: 160
Default

Nice,

Details Please. Custom Brackets? What kind of spindles or hub did you use? Rotors redrilled for 5x5" >

__________________
1966 Lemans convertible 455/5spd
1968 Firebird convertible 400/4spd
Need more Pontiacs!
The Following User Says Thank You to Tarl For This Useful Post:
  #3  
Old 04-27-2023, 10:57 AM
ScottP's Avatar
ScottP ScottP is offline
Senior Member
 
Join Date: May 2007
Location: Tewksbury, MA
Posts: 128
Default

The spindles are stock, which means this can be done on any '65-70 fullsize.
I made the hubs by turning down a set of scrap '70 rotors. I had converted
the car to 5 x 4.75" years ago when I first installed the RallyII's, so I already had
a bunch of dual-drilled rotors to pick from. The caliper mounting brackets
are made out of 316 stainless, the front adapter from 0.250" plate and the rear
from 0.500". The rotors did need to be redrilled for the 5 x 4.75" pattern.

Couple more pics showing some of these details attached.
Attached Thumbnails
Click image for larger version

Name:	UDZO6653.jpg
Views:	87
Size:	63.5 KB
ID:	611586   Click image for larger version

Name:	QVTS0322.jpg
Views:	79
Size:	55.7 KB
ID:	611587   Click image for larger version

Name:	IZSJ0901.jpg
Views:	86
Size:	76.3 KB
ID:	611588   Click image for larger version

Name:	IMG_2078.jpg
Views:	81
Size:	87.2 KB
ID:	611589   Click image for larger version

Name:	IMG_2045.jpg
Views:	83
Size:	59.6 KB
ID:	611590  


__________________
70 Bonneville convertible, Vortech V7 YSi supercharged EFI455 + 4L80E
The Following User Says Thank You to ScottP For This Useful Post:
  #4  
Old 04-27-2023, 01:05 PM
rustyrelic rustyrelic is offline
Senior Chief
 
Join Date: Dec 2005
Posts: 449
Default

Looks very impressive. I also like the idea of the more modern overdrive transmission. Sounds like a highway dream machine. Regarding your fabbed MB system, did this increase the front track width? Also when you say it could be done on any 65-70, did you mean drum spindles as well, or just with the 69/70 disc spindles? The redrilled bolt pattern certainly opens up a lot of choices in wheels. What did you do for a master cylinder and such?

  #5  
Old 04-27-2023, 02:59 PM
Ragtop Man's Avatar
Ragtop Man Ragtop Man is offline
Ultimate Warrior
 
Join Date: Sep 2010
Posts: 1,241
Default

This needs to go over to the '61-'66 and '67-70 groups!

The fab work is very impressive - and finally our big cars can stop as well as they can accelerate.

What did you do for rear discs?

  #6  
Old 04-27-2023, 09:10 PM
ScottP's Avatar
ScottP ScottP is offline
Senior Member
 
Join Date: May 2007
Location: Tewksbury, MA
Posts: 128
Default

The front track width was increased but only ever so slightly. Because the hubs
are just turned down stock rotors, the width increased by the thickness of the
hat section of the 330mm rotor, which is ~0.2" per side. I suppose if someone
wanted to duplicate this, they could take that much off the face of the hub/rotor,
as there is more than enough material there.

This setup should work with any 65-70 fullsize. The spindle assy was the same
whether the car came with discs or drums. The booster is just a stock 70 assy,
while the master is from a 94-96 Impala SS. I selected that unit a few years
back when I retrofit rear disc brakes from the same application. The single
piston D52 style caliper that came stock on my '70 is effectively identical to the
one that was used on the front of the '94-6 Bbodies, so it made that choice easy.
Attached Thumbnails
Click image for larger version

Name:	DSCN2944.jpg
Views:	43
Size:	56.2 KB
ID:	611623   Click image for larger version

Name:	DSCN2924.jpg
Views:	47
Size:	78.2 KB
ID:	611624  

__________________
70 Bonneville convertible, Vortech V7 YSi supercharged EFI455 + 4L80E
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 03:20 PM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017