'72 911e - RS Rep - Bilstien & Big Brakes????
08-10-2008, 08:42 AM
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'72 911e - RS Rep - Bilstien & Big Brakes????
Hi, I have a 72 RS Rep with a 2.2 to 2.5 MFi, std Koni suspension and small brakes. The dampers are shot, and one of the brake calipers is siezed - so its not at its best at the moment - brakes are poor.
I am working through my options for best performance v value. I will use the car for 2/3 track days pa, mostly road.
Option 1 - Bilstien stut replacement, boxster or 930 turbo calipers, master cylinder upgrade to 23mm. Cost AUD $10k
Option 2 - Koni dampers replaced, calipers refurbished. Cost $2k.
Anyone done option 1 - is it really worth it???? Did you buy the struts and calipers new from Pelican, or trust used parts?
Any other ideas?
Thanks, Stuart
I am working through my options for best performance v value. I will use the car for 2/3 track days pa, mostly road.
Option 1 - Bilstien stut replacement, boxster or 930 turbo calipers, master cylinder upgrade to 23mm. Cost AUD $10k
Option 2 - Koni dampers replaced, calipers refurbished. Cost $2k.
Anyone done option 1 - is it really worth it???? Did you buy the struts and calipers new from Pelican, or trust used parts?
Any other ideas?
Thanks, Stuart
08-10-2008, 12:39 PM
#2
Drifting
Stuart,
It depends how aggresively you'll drive car on track. I had a 72 E RS replica with the small brakes and never had any brake issues. If you are going to upgrade to Bilstien struts I would buy used and have inserts rebuilt to a custom valving for particular torsion bar you are using. Used brake calipers are fine as well, I'd go with SC or Carrera calipers and go with air venting to front rotors.
Phil
It depends how aggresively you'll drive car on track. I had a 72 E RS replica with the small brakes and never had any brake issues. If you are going to upgrade to Bilstien struts I would buy used and have inserts rebuilt to a custom valving for particular torsion bar you are using. Used brake calipers are fine as well, I'd go with SC or Carrera calipers and go with air venting to front rotors.
Phil
08-10-2008, 12:52 PM
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Hello Stuart
From your posting that the car is a RS replica and you drive some track days , tells us that you are an enthusiastic and fast driver
So... option one is your best bet. With a light car, such as yours, the choice of brakes should also include 84-89 carrera calipers as an option. What ever upgrade you do to the front will require consideration of the rear too
Turbo brakes: A)- require thick turbo rotors that are not cheap or light B)- require machining of the rear calipers to make them bolt on your control arms Braking performance is the best with this set up, but secondhand calipers have been getting pricey as supply is diminishing. Have to do front and back as a balanced system. Front only will see you braking / flat spotting your way off the track ;(
Advantages? very good braking, probably more braking performance than your light car can use (unless you are very aggressive and run on a short track)
Disadvantages? Cost and availability of second hand parts
Boxster calipers: A) require Carrera discs for the front and can use Carrera discs for the rear (remove enough material off the shiny pad support pins to allow the thicker Carrera rotor to clear)- inexpensive new B) do not require any machining or other mod to the caliper C) Requires purchase of neat adaptor kit we make
so you can bolt it all on D) must do front and rear for balanced system (Same effect as front turbo only)
Advantages? LOTS of boxsters built, so lots of secondhand calipers available for little money. Lightweight and strong calipers- monoblock casting by Brembo has yielded a very stiff design= consistent braking under hard use. Carrera discs are no more $$ than your standard 911 disc, no machining needed
Disadvantages? SOME people have experienced brake heat soak on short courses with really heavy use. This means a softer pedal. But net effect if still much better than 84/89 Carrera
Carrera option: The 84-89 calipers are bolt on to 3.5" mount ear spacing front struts. With Carrera discs f/r, you have a nice system that would work well on your light car. Secondhand calipers can be had inexpensively. Note that when fitting carrera calipers to the rear, if you don't install the limiting valve (found on the trunk floor next to the brake master in a Carrera) then bias will be to the rear. Racers like this, but its an aquiered taste. Some install the inexpensive adjustable bias valve (Summit Racing, Wilwood, etc) sold at high performance outlets. This could be your best choice given the type of driving and track use you have.
Struts: Bilstein= yes! Though not available secondhand every minute of the day, a nice pair of these is a good way to go. They will have the slightly larger spindle (your car may have the smaller ones) and the correct 3.5" spacing. Buying secondhand is a fair bet, but beware struts that are bent ! If the spacing around the cast spindle is not even, then the strut is bent. When looking at the strut, check the spindle casting first. There will be a small gap (about 1 mm) between the shock tube and the spindle casting (when viewed from above) It it is offset, then the part had suffered a bump large enough to bend the tube. Does the strut insert slide smoothly and tip engage the mounting groove on the bottom of the shock tube? If not; another indication that it is bent. AS this requires personal inspection, or a really honest seller, some extra energy is required here.
Depending on local pricing/ availability, you may just opt for new struts
Master cylinder choice
the 23 mm is not needed if you go with the Carrera calipers option. Installing a 23 reduces pedal feel and increases effort. Some (myself included) do not like this reduction/ increase combo. I personally like to feel where the brakes are at their lock up limit and the 23 makes this hard to do. BUT with that being said, the 23 mm is an option to consider when going to turbo or boxster options.
I race my Porsche with boxster calipers, carrera discs, f/r, no bias valve, and a 19 mm master. I DO HAVE TO MONITOR PAD THICKNESS CAREFULLY. Why? with the smaller master there is not enough pressured fluid volume when the pads get thin at the track
From your posting that the car is a RS replica and you drive some track days , tells us that you are an enthusiastic and fast driver
So... option one is your best bet. With a light car, such as yours, the choice of brakes should also include 84-89 carrera calipers as an option. What ever upgrade you do to the front will require consideration of the rear too
Turbo brakes: A)- require thick turbo rotors that are not cheap or light B)- require machining of the rear calipers to make them bolt on your control arms Braking performance is the best with this set up, but secondhand calipers have been getting pricey as supply is diminishing. Have to do front and back as a balanced system. Front only will see you braking / flat spotting your way off the track ;(
Advantages? very good braking, probably more braking performance than your light car can use (unless you are very aggressive and run on a short track)
Disadvantages? Cost and availability of second hand parts
Boxster calipers: A) require Carrera discs for the front and can use Carrera discs for the rear (remove enough material off the shiny pad support pins to allow the thicker Carrera rotor to clear)- inexpensive new B) do not require any machining or other mod to the caliper C) Requires purchase of neat adaptor kit we make
so you can bolt it all on D) must do front and rear for balanced system (Same effect as front turbo only) Advantages? LOTS of boxsters built, so lots of secondhand calipers available for little money. Lightweight and strong calipers- monoblock casting by Brembo has yielded a very stiff design= consistent braking under hard use. Carrera discs are no more $$ than your standard 911 disc, no machining needed
Disadvantages? SOME people have experienced brake heat soak on short courses with really heavy use. This means a softer pedal. But net effect if still much better than 84/89 Carrera
Carrera option: The 84-89 calipers are bolt on to 3.5" mount ear spacing front struts. With Carrera discs f/r, you have a nice system that would work well on your light car. Secondhand calipers can be had inexpensively. Note that when fitting carrera calipers to the rear, if you don't install the limiting valve (found on the trunk floor next to the brake master in a Carrera) then bias will be to the rear. Racers like this, but its an aquiered taste. Some install the inexpensive adjustable bias valve (Summit Racing, Wilwood, etc) sold at high performance outlets. This could be your best choice given the type of driving and track use you have.
Struts: Bilstein= yes! Though not available secondhand every minute of the day, a nice pair of these is a good way to go. They will have the slightly larger spindle (your car may have the smaller ones) and the correct 3.5" spacing. Buying secondhand is a fair bet, but beware struts that are bent ! If the spacing around the cast spindle is not even, then the strut is bent. When looking at the strut, check the spindle casting first. There will be a small gap (about 1 mm) between the shock tube and the spindle casting (when viewed from above) It it is offset, then the part had suffered a bump large enough to bend the tube. Does the strut insert slide smoothly and tip engage the mounting groove on the bottom of the shock tube? If not; another indication that it is bent. AS this requires personal inspection, or a really honest seller, some extra energy is required here.
Depending on local pricing/ availability, you may just opt for new struts
Master cylinder choice
the 23 mm is not needed if you go with the Carrera calipers option. Installing a 23 reduces pedal feel and increases effort. Some (myself included) do not like this reduction/ increase combo. I personally like to feel where the brakes are at their lock up limit and the 23 makes this hard to do. BUT with that being said, the 23 mm is an option to consider when going to turbo or boxster options.
I race my Porsche with boxster calipers, carrera discs, f/r, no bias valve, and a 19 mm master. I DO HAVE TO MONITOR PAD THICKNESS CAREFULLY. Why? with the smaller master there is not enough pressured fluid volume when the pads get thin at the track
08-10-2008, 12:56 PM
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oh- forgot to mention that we recently developed an adaptor that allows the use of the boxster caliper on your Koni strut with 3" spacing. So if your konis are straight, you can save a few more $$
08-11-2008, 10:27 AM
#5
Through '73 most 911s got along fine w/ S brakes, yes I would want Billstein 3.5" struts
another option is to leave their rears alone and just mount 3.2 Carrera calipers and rotors on the front, no other changes are needed.
The advantage is
1) no bias change
2) no p/v needed, 3.2 Carrera f/r will want an aggressive p/v
3) the rear doesn't generally get hot enough to need an upgrade any way. When it is upgraded it's usually to balance out the front upgrade.
4) it's the cheapest caliper/rotor pgrade available.
5) no other changes are needed, stock m/c is fine
another option is to leave their rears alone and just mount 3.2 Carrera calipers and rotors on the front, no other changes are needed.
The advantage is
1) no bias change
2) no p/v needed, 3.2 Carrera f/r will want an aggressive p/v
3) the rear doesn't generally get hot enough to need an upgrade any way. When it is upgraded it's usually to balance out the front upgrade.
4) it's the cheapest caliper/rotor pgrade available.
5) no other changes are needed, stock m/c is fine
08-11-2008, 07:43 PM
#6
Drifting
g'day Stu
there are some great upgrades that wont cost you the earth...a search on renny or pelican will turn up a few options
for starters: http://forums.pelicanparts.com/showt...ferrerid=42314
yet another option is boxster front & carrera rear
there are some great upgrades that wont cost you the earth...a search on renny or pelican will turn up a few options
for starters: http://forums.pelicanparts.com/showt...ferrerid=42314
yet another option is boxster front & carrera rear
08-19-2008, 05:26 AM
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Stuart,
It depends how aggresively you'll drive car on track. I had a 72 E RS replica with the small brakes and never had any brake issues. If you are going to upgrade to Bilstien struts I would buy used and have inserts rebuilt to a custom valving for particular torsion bar you are using. Used brake calipers are fine as well, I'd go with SC or Carrera calipers and go with air venting to front rotors.
Phil
It depends how aggresively you'll drive car on track. I had a 72 E RS replica with the small brakes and never had any brake issues. If you are going to upgrade to Bilstien struts I would buy used and have inserts rebuilt to a custom valving for particular torsion bar you are using. Used brake calipers are fine as well, I'd go with SC or Carrera calipers and go with air venting to front rotors.
Phil
Apologies for the delay I have been overseas... Thats interesting you didnt need the upgrade... I am typically very easy on my cars on track days... maybe I just need to refurbish my calipers... although buying a good used SC set maybe the same price...
Did you do any other mods to your RS Rep?
Cheers, Stu
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08-19-2008, 05:29 AM
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Hello Stuart
From your posting that the car is a RS replica and you drive some track days , tells us that you are an enthusiastic and fast driver
So... option one is your best bet. With a light car, such as yours, the choice of brakes should also include 84-89 carrera calipers as an option. What ever upgrade you do to the front will require consideration of the rear too
Turbo brakes: A)- require thick turbo rotors that are not cheap or light B)- require machining of the rear calipers to make them bolt on your control arms Braking performance is the best with this set up, but secondhand calipers have been getting pricey as supply is diminishing. Have to do front and back as a balanced system. Front only will see you braking / flat spotting your way off the track ;(
Advantages? very good braking, probably more braking performance than your light car can use (unless you are very aggressive and run on a short track)
Disadvantages? Cost and availability of second hand parts
Boxster calipers: A) require Carrera discs for the front and can use Carrera discs for the rear (remove enough material off the shiny pad support pins to allow the thicker Carrera rotor to clear)- inexpensive new B) do not require any machining or other mod to the caliper C) Requires purchase of neat adaptor kit we make so you can bolt it all on D) must do front and rear for balanced system (Same effect as front turbo only)
Advantages? LOTS of boxsters built, so lots of secondhand calipers available for little money. Lightweight and strong calipers- monoblock casting by Brembo has yielded a very stiff design= consistent braking under hard use. Carrera discs are no more $$ than your standard 911 disc, no machining needed
Disadvantages? SOME people have experienced brake heat soak on short courses with really heavy use. This means a softer pedal. But net effect if still much better than 84/89 Carrera
Carrera option: The 84-89 calipers are bolt on to 3.5" mount ear spacing front struts. With Carrera discs f/r, you have a nice system that would work well on your light car. Secondhand calipers can be had inexpensively. Note that when fitting carrera calipers to the rear, if you don't install the limiting valve (found on the trunk floor next to the brake master in a Carrera) then bias will be to the rear. Racers like this, but its an aquiered taste. Some install the inexpensive adjustable bias valve (Summit Racing, Wilwood, etc) sold at high performance outlets. This could be your best choice given the type of driving and track use you have.
Struts: Bilstein= yes! Though not available secondhand every minute of the day, a nice pair of these is a good way to go. They will have the slightly larger spindle (your car may have the smaller ones) and the correct 3.5" spacing. Buying secondhand is a fair bet, but beware struts that are bent ! If the spacing around the cast spindle is not even, then the strut is bent. When looking at the strut, check the spindle casting first. There will be a small gap (about 1 mm) between the shock tube and the spindle casting (when viewed from above) It it is offset, then the part had suffered a bump large enough to bend the tube. Does the strut insert slide smoothly and tip engage the mounting groove on the bottom of the shock tube? If not; another indication that it is bent. AS this requires personal inspection, or a really honest seller, some extra energy is required here.
Depending on local pricing/ availability, you may just opt for new struts
Master cylinder choice
the 23 mm is not needed if you go with the Carrera calipers option. Installing a 23 reduces pedal feel and increases effort. Some (myself included) do not like this reduction/ increase combo. I personally like to feel where the brakes are at their lock up limit and the 23 makes this hard to do. BUT with that being said, the 23 mm is an option to consider when going to turbo or boxster options.
I race my Porsche with boxster calipers, carrera discs, f/r, no bias valve, and a 19 mm master. I DO HAVE TO MONITOR PAD THICKNESS CAREFULLY. Why? with the smaller master there is not enough pressured fluid volume when the pads get thin at the track
From your posting that the car is a RS replica and you drive some track days , tells us that you are an enthusiastic and fast driver
So... option one is your best bet. With a light car, such as yours, the choice of brakes should also include 84-89 carrera calipers as an option. What ever upgrade you do to the front will require consideration of the rear too
Turbo brakes: A)- require thick turbo rotors that are not cheap or light B)- require machining of the rear calipers to make them bolt on your control arms Braking performance is the best with this set up, but secondhand calipers have been getting pricey as supply is diminishing. Have to do front and back as a balanced system. Front only will see you braking / flat spotting your way off the track ;(
Advantages? very good braking, probably more braking performance than your light car can use (unless you are very aggressive and run on a short track)
Disadvantages? Cost and availability of second hand parts
Boxster calipers: A) require Carrera discs for the front and can use Carrera discs for the rear (remove enough material off the shiny pad support pins to allow the thicker Carrera rotor to clear)- inexpensive new B) do not require any machining or other mod to the caliper C) Requires purchase of neat adaptor kit we make
so you can bolt it all on D) must do front and rear for balanced system (Same effect as front turbo only) Advantages? LOTS of boxsters built, so lots of secondhand calipers available for little money. Lightweight and strong calipers- monoblock casting by Brembo has yielded a very stiff design= consistent braking under hard use. Carrera discs are no more $$ than your standard 911 disc, no machining needed
Disadvantages? SOME people have experienced brake heat soak on short courses with really heavy use. This means a softer pedal. But net effect if still much better than 84/89 Carrera
Carrera option: The 84-89 calipers are bolt on to 3.5" mount ear spacing front struts. With Carrera discs f/r, you have a nice system that would work well on your light car. Secondhand calipers can be had inexpensively. Note that when fitting carrera calipers to the rear, if you don't install the limiting valve (found on the trunk floor next to the brake master in a Carrera) then bias will be to the rear. Racers like this, but its an aquiered taste. Some install the inexpensive adjustable bias valve (Summit Racing, Wilwood, etc) sold at high performance outlets. This could be your best choice given the type of driving and track use you have.
Struts: Bilstein= yes! Though not available secondhand every minute of the day, a nice pair of these is a good way to go. They will have the slightly larger spindle (your car may have the smaller ones) and the correct 3.5" spacing. Buying secondhand is a fair bet, but beware struts that are bent ! If the spacing around the cast spindle is not even, then the strut is bent. When looking at the strut, check the spindle casting first. There will be a small gap (about 1 mm) between the shock tube and the spindle casting (when viewed from above) It it is offset, then the part had suffered a bump large enough to bend the tube. Does the strut insert slide smoothly and tip engage the mounting groove on the bottom of the shock tube? If not; another indication that it is bent. AS this requires personal inspection, or a really honest seller, some extra energy is required here.
Depending on local pricing/ availability, you may just opt for new struts
Master cylinder choice
the 23 mm is not needed if you go with the Carrera calipers option. Installing a 23 reduces pedal feel and increases effort. Some (myself included) do not like this reduction/ increase combo. I personally like to feel where the brakes are at their lock up limit and the 23 makes this hard to do. BUT with that being said, the 23 mm is an option to consider when going to turbo or boxster options.
I race my Porsche with boxster calipers, carrera discs, f/r, no bias valve, and a 19 mm master. I DO HAVE TO MONITOR PAD THICKNESS CAREFULLY. Why? with the smaller master there is not enough pressured fluid volume when the pads get thin at the track
Looking at your comments, Bill's, and Phil's I reckon the 3.2 front upgrade (disk and calipers) and the Bilstiens all round will work well.
I am also planning to get all the bushes done at the same time - any preferences????
Thanks agian guys, Stu
