RC713

I purchased a shell from a lister up near San Fran that will be the start of a long term (12-18 months likely) LS1 build. The shell is from an 87 951 which would have had the late offset. As the PO stripped off and sold the big $ suspension I will be needing the whole package. It is my understanding (please correct me if I am wrong) that as long as I keep everything consistent I could go with either an 86 (early correct?) Or 87+ (late, right?) Offset setup for suspension, wheels, etc? So, lonq question longer, first, is this correct, and second, is there an advantage to going with either one? Cheers, -Reid

M758

late offset works with ABS, Early offset does not.

For track use the late offset is better on paper. For street use it comes down what wheels you want to used. Later Porsche OE wheels will fit on late offset suspension. Fuchs and older vintage wheels fit on early offset suspension.

User 52121

In addition to M758's comment about offsets and ABS...

A local Porsche specialist shop, back when I was still shopping for a car, was pretty insistent that the late offset stuff was stronger/more durable than the early stuff. Though in the end, they admitted that they hadn't seen a single failure on the early offset stuff in all the years they'd been involved in Porsche racing (Midwest Eurosport, they've been around awhile.) So I'm not sure how well the "durability" argument actually holds water.

One advantage to late model suspension is easier brake rotor changes. With the early stuff you need to disassemble the front hubs to get the front rotors off. Late offset is just like most other cars: the hub/wheel bearing assembly is behind the rotor and doesn't need to be touched to pull the rotors off.

My bet is that if you can find early stuff, it'd probably be cheaper since most folks want the late offset so they can run the later factory wheels.

931guru

+1 - Late offset is stronger!

Lemming

In addition and food for thought.

Late offset spindles and hubs allow for larger brakes and easier pad changes. However, late offset spindles and hubs can be used with early offset control arms in the front. Early steel arms are cheap ($25 new), can be strengthened, and the ball joint is easily replaced. Spacers can be used to increase the wheel width if wanted. Downside is that if you have a lowered car you cannot buy longer pins to correct the geometry.

You want the alum arms in the rear.

ideola

To add to the above, the late offset spindles have a larger diameter than the early spindles where the hub sits on the spindle (and are therefore stronger, theoretically).

Now for the weird part. You have to be careful about mixing and matching early and late stuff. Believe it or not, there were at least four iterations of spindles on the street-destined 944 series:

• Very early spindles that were on steel A-arm cars have smaller diameter hub (31.7mm), 76.5mm caliper bolt spacing, a 58mm strut housing bolt pattern, and a 20mm wide flange for the strut housing.
• The 86 951 spindle was very unique. It has the early hub diameter (31.7mm), 94mm caliper bolt spacing (to accommodate the Brembos), and had the late offset strut housing setup (63mm strut housing bolt pattern, and an 18mm wide flange). These spindles may have made it onto other 944s from 1985.5 thru the end of the 1986 model year that were equipped with the M030 package, but I've not been able to confirm this conclusively. These would have come with the early offset alu A-arms. I believe the non-M030 944s of that 1.5 year period would have used the earlier spindle described above, but bolted onto the alu A-arm.
• The 87-onward 951 spindle had the larger hub diameter (35mm) with 94mm caliper bolt spacing, and the same strut housing dimensions above.
• The 87-onward non-turbo and non-M030 cars had spindles that were just like the 951 except for the caliper bolts spacing, which was the smaller 76.5mm pattern to accommodate the single pot floating calipers.

So you have to be very clear about what you're trying to do with the car. The A-arm is the only thing that affects the front offset, and any of the spindles will bolt onto any of the A-arms (steel, early Alu, or late Alu). BUT you have to be sure the spindles you get give you:
1. the hub configuration and size that you want
2. will work with the strut housings you wish to utilize
3. will work with the calipers you wish to utilize

You can't easily mix and match early strut housings with late spindles and vice versa. Mods to the strut housing bolt pattern are not advisable because there's insufficient material to safely slot the holes, either on the strut housing or the spindle. So you need to match the spindle to the strut housing, as well as to the brakes you intend to run.

Hope this makes sense. You can download a spreadsheet from my website that might help clarify some of the above data points:
http://garage.ideola.com/downloads.html
Fourth item down in the left hand column, document entitled "924/944 Spindle Metrics"

ideola

I should add that there may be yet other spindle and hub permutations, these are merely the ones I've personally been able to document.

75ohm

Reid, parts are flying out fast man... I still have the front rotors and the late strut setup...

teamking

One more thing to add to this from my experience (with an 86 951 that updated to late offset spindles/hubs/rotors from an S2) is that the later (87+) spindles expect the strut to be sitting at a different angle than the 86 951 spindles, and thus you LOSE about 2* of negative camber if you go with early offset arms and late spindles (and hubs and rotors). You can get back to factory camber with camber plates, but not enough for racing. I'm hoping to solve this my slotting the holes in my struts, but it's not something you want to deal with. Bottom line: 1) don't use 86 951 spindles, and 2) don't mix early offset control arms with late spindles.

ideola

teamking, you're right on the money with that...although remember the alu arms have an adjustment at the rear mounting point that can be used to help with some of that, which is another significant advantage of the alu arms over the steel arms. On one of my projects, I'm going to attempt putting late offset spindles and struts on a narrow body 931 with early offset alu arms and camber plates up top. Hope to have some initial findings within a month or so, just waiting for a couple of bits (bushings and spring hats) before bolting it all up. Of course, in my case, I have to use the early offset arms because the late offset will push the wheels out too far for the narrow body. I'd use the 86 951 spindles, but I already have complete 968 assemblies including rotors, and don't want to have to go backward to the PITA 86 rotor setup.

PorscheDoc

Yup, just install all 87+ stuff. Easier to change rotors, a lot better selection of wheels that fit, stronger spindles etc. It's a no brainer if you are starting from scratch.

PorscheDoc

I run 87 spindles on early offset arms and run -2 degrees of camber and I have plenty of adjustment left on the camber plates to go more.

ideola

As long as you're on a 944 platform...late offset won't work on the narrow body cars (not all of us are '44 owners ). For the narrow body cars, the easiest adaptation is the '86 951 setup, which maintains early offset required for narrow body, allows Brembo upgrades front & rear, and expands the available range of shocks and coil overs that can be added to the car.

The biggest drawback is that the 86 spindle doesn't have the required speedometer cable hole (which, btw, is something to be aware of if you're upgrading ANY pre-85.5 car...none of the post 85.5 spindles have this hole, so you'll need to drill your late spindle or figure out a way to rig up electronic speedo if you're on an early 944, 924S, or early 924/931).

The cool thing about the early body cars is that you have the option of sticking with the rear steel trailing arms and front steel A-arms (which opens up opportunity to reinforce them), or switching to the early offset alu setups weight savings is more important than strength.

Another thing to be aware of is that your choice of rear trailing arms will dictate what you can do with rear shocks, as the lower shock mounts have different sized bolts. You can bolt late shocks on steel trailing arms, but it would involve hogging out the holes and shimming the shock mount with spacers.

PorscheDoc

My post was in reference to the original poster saying the shell was an 87 951.

teamking

Interesting. I'm maxed out at -1.5*. What struts are you using?

I'm running stock struts currently, and have heard that Koni's won't help but that LEDA's are drilled to allow for a little more negative camber.

I'm also running with Racer's Edge control arms (early offset), camber plates, and caster blocks.