924Board.org

[sandgroper]

I would like the 4pots off the 944 turbo to go on the front of my 80model 931 turbo.1, has anybody done this and has first hand experiance.
2,i know their is a difference in calipers changing i think in the 87 model year.
3,i wish to change from the diagonal split circut to the front/rear circut and put a bias valve inline to the rear brakes.I already am running 16 inch 928rims.
4,so parts wise what do i need exactly,spindles etc,etc.

[john h]

Been there, in the process of doing the same thing.

I'm using the "black" calipers complete with the 944 hubs discs etc. Seems to be a straight bolt in.
The only problem I've got at present is the 944 rims I'm using (cookie cutters) foul on the wheel - So I'm using longer studs and a 10mm spacer on the hubs to stop the rims hitting the caliper.
Parts wise you need all the early 944 hub. ie everthing between the lower arm and the strut (you don't need the strut). For the master cylinder you can use a 944 stepped master cylinder(19 and 23mm bores) and then run the fronts off 23mm cylinder and rears off the 19mm cylinder. To do this you will need to run a new line to the left rear, and blank of the exisiting left rear were it exits a T union just under the floor on the right hand side foot well.
_________________
Remember a Porsche is not just for Christmas,

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

[sandgroper]

Thanks John,so i will look for 86 turbo complete front hubs and brakes and go the 944 M/C,i would like to use the alloy rear trailing arms from the later model cars do you have any knowledge on them,ala 924S.
Dropped my spare crank off at grinder and will get almost 3mm extra stroke out of crank using mitsubishi spec rods,the eagle rods are 550 grams so considerably lighter and then custom pistons will bring that total weight down again.Have a nice bar and plate front mount intercooler in the works so cant wait to complete mods.

[john h]

Don't know anything about the rear alloy arms - suggest you see if Gohim knows anything.

What model of Mitsi do the rods come from _ I've just been to Brisbane and didn't see any Eagles over there mind you I wasn't really looking at Jap car names but did notice a few Comodores badges as Toyota's and a few of those Holden Appollo things which we called Toyota Camry's over here.
_________________
Remember a Porsche is not just for Christmas,

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

[gohim]

To put the alloy trailing arms on you will also need the spring plates, the cv axles (because they are longer), and figure out what to do about the shock mounting bolts.

The alloy trailing arms are set up for larger diameter shock mounting bolts than the steel trailing arms. If you use the shocks that are meant to be used with the alloy trailing arms, then you will have to either ream/enlarge the shock mounting bolt holes on the body for the upper shock mounts, or make a bushing to fit inside of the shock end to allow the use of the smaller diameter bolt that the body was originally designed for. With the use of the alloy trailing arms, the spacers are no-longer needed, and the length of the lug bolts on the wheels hubs are shorter.

[sandgroper]

John,its the 4G63 2.0 pre 92 engine they came turbo or n/a,has a slightly wider big end width than later 4G63 engine which is barely wider than stock rod,so the grinder is grinding the rod journals to suit.I bought aftermarket eagle brand billet rods to mitsi specs have a friend o/s that got them for me.
Thanks gohim,i think i will go alloy arms route,could just bush the bottom eye of stock shock to suit larger bolt right?.

[gohim]

If you decide to do the alloy trailing arm conversion, you need to get the shocks that go with them.

You will need to make or buy bushings to fit the upper mounting holes of the shocks to reduce the size of the mounting bolts to those used by the existing body mounts.

You should not use the old shocks, because the lower shock mounting eyes are smaller than the ones for the alloy trailing arms. Porsche increased the size of the shock mounting bolts for a reason.

I spent a fair amount of time looking at this conversion, and seriously considered doing it while I was doing the four wheel disc brake conversion. But I decide not to do it, even though I like the alloy trailing arms (because of the significant weight savigs and increase in the trailing arm rigidity). I am not thrilled by the fact that the rear wheel bearings are sealed, that they are not servicable (cannot be repacked with grease), require some special tools to replace, when the time comes for replacement, and cost more than the servicable wheel bearings installed in earlier 924, and 844 models.

[-nick]

a couple other complications when switching to the alloy arms-

from what i can tell you can only use arms from a 924S or an '86 951. somehow porsche made the wheels stick out further the other 944 models using the alloy arms. i don't know if the offset is changed with the arm or the hub, but the 924S and '86 951 part number is different than all other years. remember the '86 951 used a smaller offset wheel to push them out.

second, i think the torsion carriers maybe different. specifically the angle in the mounting of the alloy arm pivot.

i haven't confirmed this and i'm not sure what parts gave the offset change. just something to think about.

one last thing- i've heard of the arms shearing on track cars. i know a couple guys that keep a spare set around. not a problem with the steel arms.

-nick

[sandgroper]

[john h]

They seem to work fairly well (in fact much better than the single pot units).
As I've got the split front rear all I notice is that it stops quicker.
Next I'm trying to graft a set of AP four pot caliphers (from an Austin Princess to the back). some initial measurements indicate they will fit the Porsche mounting holes so they could be an quick fit.

Once I figure out how to do this the brakign shoudl be really good.
_________________
Remember a Porsche is not just for Christmas,

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

[Zuffen]

The front arms are basically same for all the 924 and series one 944, the difference is the sway bar mount.

The spindle is the same also for the 924 to the series one 944 (82-85)and series two (85.5-86) up to the end of 86.

The 86 944T has a different spindle probably to mount the larger caliper.

This can be testes by looking at the two calipers and measuring the mount holes.

The struts are the same for the 924 and 944, but it gets confusing when you look at the turbo and the 474 option (sport suspension)

The option is available for both the 944 and turbo.

The turbo has a different strut assembly number but that may have anything to do with the actual strut housing but the insert and spring may be the difference.

The mount bolts for the bottom are the same, so unless the turbo has a larger diameter housing I can't see what makes any housing different. ABS wasn't on the 86 turbo, so the number change must be for the strut assembly.

One thing that I was told but unconfirmed is that the spacing on the bottom holes is different. If you have a 951 strut from an 86 and compare it to the strut from a NA 944 the spacing is unequal.
If there is a difference, than modification to the strut housing shouldn't be difficult and under that idea a 951 spindle whould bolt right into place on 924/944 strut.
_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

[Zuffen]

There rear AL arms look like the brakes are a bolt in and change out the rotor

same for the 924s and 86 944, the M030 has a modification to basically the same arm, probably a larger shock pin

in 87 they make a change to the hub
_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

[Vince Ponz]

A friend changed the rotors and brakes on his 944 and he had to have a mount made to accommodate the calipers. Something like one set has the mount holes on one side but turned sideways on the new ones. When he had the mounts made by a machinist he had three sets made for the cost to make one was almost as much as the three once the machines were set up. He still has two sets available for sale.
Let me know if you have problems and I will forward his email address.
_________________
"Never let them see you sweat"
77.5 924 modified track car
79 931 Euro stock
88 924S SE
87 911 Targa stock