924Board.org

[Euro924S2]

Hi Guys. With my MP62 supercharger setup working great, I'm moving onto stage 2 of the project. For background I have a 924NA with a 931 engine. This next stage involves changing to 944 t.tube, hydrolic clutch, and 944T gearbox etc.

My question however is concerning my planned brake upgrade. I've read a WHOLE load of previous threads on this popular topic but I am completely confused!!! Hopefully there is a straight forward answer to my dilema!!

So, I have a standard bodied 924 AKA no CGT kit etc. I have 17" x 7J alloys with an ET 32 but which require bolt pattern converters with a minimum thickness of 15mm.

I currently have the standard 924 hubs and rear trailing arms, but I have a 931 donor car to provide parts as needed.
I have bought a full matching set of 944 S2 Brembo calipers and the discs which is what I want to use.
Unfortunately, the 944S2 discs go over the front hubs, not behind like the 931 ones I have! (I haven't looked at the rears yet)

Incase it's any use I also have a complete 944 Turbo rear end (without brakes) although I suspect this will be too wide for my 924 body.

So my question is:

1) are the 944S2 discs compatible with my 931 rear end parts

2) what is my best option for the front? buy the 944S2 hubs but use my 931 stub axles? or buy the 944S2 hub and stub axle, but use my wishbone?

Importantly, i have ajustable spax dampers which have only done about 4K miles so I don't want to have to change these.
Also, i'm not so fussed about the speedo, so if i loose that drive it's no biggy!!

Thanks again, cheers, john.
_________________
UK spec '83 N/A with 931 motor with Eaton MP62 'charger @ 15psi. EFI - 565cc inj. Standalone Adaptronic ECU. 951 FMIC. Ally rad. Twin throttle. Recirc valve. Custom manifolds and CAI. 232bhp

[BionicBalls]

From my understanding of the topic, you need control arms and hub/spindle assembly from a '86 951 in order to fit the brembos.

I believe that the 944 rear end will fit and work just fine, might need some modification to get the shock assembly in order.

Dan (Ideola) has extensive knowledge of this so hopefully he'll comment, but I'm fairly sure that the '86 944 is the easiest (most bolt on) option for upgrading the front brakes.
_________________
1980 924 NA
1982 931

[Euro924S2]

Thanks bionic. 86 parts I've read a lot about, although over here (in uk) they seem more rare than 924GTR's!!! Dan has written a fantastic write up (again ) covering brake options and considerations in his Project planning thread, so I hope he can clarify a few more points, with input from others who have walked this road already!

From my understanding, given the parts I already have I have 2 main options: (relating to the front)

1) keep my A arms but fit the 944S2 hub and spindle assembly.
Benefits: calipers bolt on with no bracket, I already have the discs to fit.
Draw-back: I loose my speedo drive (not a disaster) but more significantly my spax adjustable inserts may be no use. I know the bolt pattern for the strut housing is different on the later spindles, but can I not either elongate the holes or weld a plate on top of my strut flange with the later bolt pattern and use slightly longer bolts to sandwich my strut flanges between (obviously I'd have to elongate the holes to allow the bolts to pass through. )

My question with that setup however is would my wheels be thrown too far out - or does keeping my steel A arms keep the offset the same?

2) From reading, if I buy a pair of early (85) 944 Turbo brake discs, these mount behind the 931 hubs and are the same size (thickness and diameter) as the 944s2 ones. The problem there is I can't bolt the Brembo callipers straight to the 931 spindle knuckle. I've searched the net for about 2 hours last night but I can't find a source for an adapter bracket. There are lots of brackets to mount the radial style Boxster brembo's but not the traditional mounting 944T/S2 ones?

I'm I correct in this understanding and if so does anyone know of a source for the correct brackets?

Cheers. John.
_________________
UK spec '83 N/A with 931 motor with Eaton MP62 'charger @ 15psi. EFI - 565cc inj. Standalone Adaptronic ECU. 951 FMIC. Ally rad. Twin throttle. Recirc valve. Custom manifolds and CAI. 232bhp

[simsport]

Hi
What kind of power/torque are you getting with 12psi?

I am about to modify my m62 blower to give more/cooler boost.

cheers
simon
_________________
Blown is always best!

[Euro924S2]

Hi simon. I'll PM you to keep this on topic - been looking at the parts I have again - hmmmmm!! Definately still need some expert knowledge!!!
_________________
UK spec '83 N/A with 931 motor with Eaton MP62 'charger @ 15psi. EFI - 565cc inj. Standalone Adaptronic ECU. 951 FMIC. Ally rad. Twin throttle. Recirc valve. Custom manifolds and CAI. 232bhp

[morghen]

the main question is if you can use 951(or late 944) hubs on the 931(early 944) spindles. if so...then you can have the bigger thicker disks installed and the big calipers installed with an adapter.

based on the common knowledge this is possible.
i'm going to do the same.

931 spindles
951 hubs
928 S4 disks
928 S4 calipers (big reds) with an adapter.


as a side note. your injectors sound way too big for 12psi to me...you should be running max 330 injectors for that boost/power
_________________
Supercharger and EFI kits
https://www.the924.com

[Dutch924-racer]

I thought the 944 S2/ 968 spindels where thicker, so the 931 hub won't fit.

I went for a full 944 S2/ 968 conversion (spindles. hubs, rotors, etc.)
_________________
937 trackday car
Series 2 engine
951S turbo and intercooler
Fast road camshaft
Forge recirculation valve + boost controller

[morghen]

check this out





_________________
Supercharger and EFI kits
https://www.the924.com

[Raceboy]

Late 944/951 hubs don't fit to 931/early 944 spindles!

I know this for a fact because I have both and late hub has different wheel bearings and has larger inside diameter.

If you want to go 951 S/928 S4 front brake route, you need late spindles also, best option would be 951 S spindles as no caliper adapters are needed but these are expensive and quite rare.

(Much) cheaper option is to buy late 944 NA spindles and fabricate simple caliper adapters.

Oh, you have to drill the spindle for speedo cable also, I did it for 931 "Gulf" but I don't have a speedo cable (it is broken on two of my cars, only white one has it, lol).
_________________
'83 924 2.6 16v Turbo, 470hp
'67 911 2.4S hotrod
'90 944 S2 Cabriolet
'78 924 Carrera GT replica
'84 928 S, sold
'91 944 S2, sold
'82 924S/931 "Gulf", sold
'84 924, turbocharged, sold.
http://www.facebook.com/vemsporsche

[morghen]

are there such things as early 951 hubs? hubs that fit on the early 944/931 spindles but have the disk over not under?

better yet...what stops one from installing the late disks on the early hub? that indexing/positioning screw hole?
_________________
Supercharger and EFI kits
https://www.the924.com

[Raceboy]

[morghen]

then thats it, the only "price performant" recipe that works:

late 944 spindles with hubs, big calipers and disks + made adapters.

as a side note...when you install 951S spindles and hubs you also need 951S strut towers...as the bolt pattern is different. (please confirm this last bit)
but late 944 spindles use the same bolt pattern at the strut tower assembly as the early 944/931 strut tower. (please confirm)
_________________
Supercharger and EFI kits
https://www.the924.com

[Raceboy]

You can modify the strut mounting holes. Not the best option but it works and has been done many-many times.
_________________
'83 924 2.6 16v Turbo, 470hp
'67 911 2.4S hotrod
'90 944 S2 Cabriolet
'78 924 Carrera GT replica
'84 928 S, sold
'91 944 S2, sold
'82 924S/931 "Gulf", sold
'84 924, turbocharged, sold.
http://www.facebook.com/vemsporsche

[Dutch924-racer]

I used the later type (after 1987) struts.
_________________
937 trackday car
Series 2 engine
951S turbo and intercooler
Fast road camshaft
Forge recirculation valve + boost controller

[john h]

I used the early 951 (220 hp_ front hubs and had the top bolt hole machined to match the original front strut assembly and then fitted the whole unit to the pressed steel 931 A arm. After slotting there was a reduced amount of metal at the edge of the hole so we build this up weld and flat bar to ensure adequate metal on eth edge. Also the slotting was done on a slight angle so that more negative camber can be dialled in while still keeping the original camber adjustment on the front strut, little bit of subtle modification for keeping standard mounting and suspension adjustment points.

For the rear I used a complete 951 rear end modified to enable the 931 gearbox to be bolted to the suspension as per original 931.
_________________
Remember a Porsche is not just for Christmas,

if you take it to pieces slowly it can provide anguish all year long!