Ok I understand swapping the struts for the 5 lug conversion.

The 930 tie rod swap makes sense.

Why swap the arms, crossmember, torsion bars?

The torsion bars are heavier and at a rate meant for a heavier car.

The aluminum crossmember although it is lighter it is known to fail due to fatigue / corrosion

The geometry of the arms looks to be identical, so no advantage there.

So why spend the money on it? Help me understand why people spend the money.

Bragging rights.

Ventilated rotors independent of the hub and 5 lug wheels vs re-drilled nonvented 4 lug rotors for starters. Cool factor.

instant stopping power

Often this is available as a package from a wrecked car. Or used to be. That was my reason. I found that the torsion bars from that 1985 911 were just right. Of course the weight in those cars wasn't primarily in the nose end. I did have some issues with the belly pan, so it isn't all good.

you are right on the money, no reason what so ever. Even if one is racing, they can purchase bigger torsion bars to fit in the 914 a arms.
One of the reasons they do it though is that they buy the whole set up in one piece and just bolt it in in that one piece

Some of you guys missed the part where I said I understand the struts (which would include the brakes).

I can get any rate torsion bar from Sway-a-way to fit the stock arms and torsion adjusters.

So there is no advantage other than telling people you have 911 front suspension.

911 availability is very good.
914 not so much.
If a part crosses over to 914 land and you can use it, why not.

You are correct. There is no reason to swap A-Arms or the cross member unless one wants the aluminum cross member. Been running that way with just 911/930 struts/Brakes since 1988.

I swapped the -4 back as the 911 stuff was too stiff. Changed my Elephantah bushings to the -4 arms and got a better ride. Carerror only weights in at 1609 lbs.

+1; I'm only using 911 struts for the 5lug conversion and vented rotors.
my A arms, torsion bars, and crossmember are still 914

I'm with jmitro, only struts/vented rotors...914 a-arms, cross member.

Ease of installation ...

6 bolts on top, 8 bolts on the bottom, done. No need to pop ball joints or any other some such nonsense.

Not heard of a alloy cross member failing,they are a very sold casting,good enough for Porsche to use in there racing cars.
It has to be remembered that many of these conversions are done to high powered 6 cyl cars, better braking is important in that case.

I'd have to agree.
Those alloy cross members don't fail by fatigue.
I've extensively autocrossed and club raced a 911 will an aluminum cross
member for going on 30 years.
No issues at all.

And corrosion on an alloy cross member?
Certainly no worse than a steel cross member....I'd think better than bare steel.

If you do change out the A-arms to 911 versions, you have to change out the torsions bars as well....you can't use 914 torsion bars in 911 A-arms.
The spline count is different on the A-arms between 911 and 914's.
Some choose to upgrade or increase the size of the torsion bars even on relatively stock 914's.
Too me, they were too soft from the factory.
Most stock 914's lean considerable in a turn and really nose dive under hard braking.
Not exactly safe in my book.
So a little more stiffness brings about nice cornering and stopping power without being too stiff, and adds a dimension of safety as well.
I'm doing a narrow body conversion and to me the stock springs/torsion bars are just too soft for normal and performance street driving.

The comment about more products available for 911's is true.
I waited 9 months to get a set of 21mm 914 torsion bars.
If I'd had the 911 A-arms, they were on the shelf.

I believe the front wheel bearings on a 911 are larger and more robust than 914 versions.



So as you can see there are many valid reasons to go with some 911 front suspension components.
I think the last reason would be bragging rights....as least in my case.
I wanted bigger brakes, better and lighter suspension components (alloy cross member and alloy S calipers).
The only way for me was to go with some 911 components.
Luckily it all bolts in.

Additionally, most of my suspension and brake components were so old, rusty and worn out that it was a great time to upgrade much of it.

Torsion bars are larger if using the stock bar.

You want to run the underbody swayer to save pulling the tan, etc....

You have it out of the car so you can clean it up, and get it setup, cleaned and colored coated in your favorite coating. Everything else is the same.

Struts only for me. -6 brakes on 4 corners with 19mm master cylinder and factory sway bars. 16x6 reproduction Fuchs with 225 55 16.

The only 914 parts left on my front end are the steering box and A arms. 21mm torsion bars and alloy crossmember. Elephant bushings.

The 3 1/2" 911SC front struts give you a few more brake caliper choices. I'm running a 911 belly pan which is heavier, but quite bombproof.

Most of the stock 914 pans I've seen are battered.

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The more products for 911 only comes into play with torsion bars, everything else crosses over.

I've talked to the guys at Sway-a-way and it's 3-5 days to get a set of bars.

I prefer the thru body sway bar for simplicity of design and service.

I've seen a few failed aluminum crossmembers in my research. Nothing drastic mostly just hairline cracks and corrosion around the bolts.

So performance vs money

Stay with the 914 stuff, add good bushings and torsion bars and be happy.

My AutoX car didn't come with sway bars, so I swapped in the 911 arms w/ torsens, ALx and stock under body swaybar.

My Nissan swapped car also didn't come with swaybars, so it got the full Carrera swap but replaced the ALx with the stock steel tube and ran the radiator hoses over it.

I have never heard of the ALx failing in 28 years, and that includes when we cut holes in them for radiator hoses at Renegade.

If you don't need/want stiffer torsen bars then no reason to use 911 arms.
Given the $$ of Alx these days the # per $ isn't worth it.

It was common to buy the whole front susp drop. These days the same money buys just struts and hubs, calipers are a separate expense.

I’ve seen six broken aluminum crossmembers in the last 2 years but it’s almost always due to accidents and hard curb hits. The steel ones bend, the alloy ones crack. I’ve seen some corrosion on the alloy ones but not much for their age.

Because it looks prettier......
Click to view attachment

+1

Depending whom I am talking to if someone asks me, I have a 911 front suspension.

Easier than saying I have 3.5" spacing 911 struts w/Bilstein inserts and 911 front hubs .

Click to view attachment

Man, is that ever a memory. Fun day!

I've 5-lugged both 914's that I've owned. One of the most rewarding swaps and quite easy to do. In one evening my 914 went from 4-lug VW hubs to 5-lug 911. 5-lug Fuchs look great on a 914.

The 914-4 and 911/914-6 have different spline count on the torsion bars also, so no mixing and matching allowed. So each A-arm and adjuster cup also have to be matched. If you do you would need to keep them on the same side of the car. Nothing saying you can't use a 911 A-arm and a 914-4 Arm, they just need to have everything matched.

Also while on the conversation of spline counts. the rear the input shaft and the hub are also specific to the 914-4 and if using 914-6 or 911 parts they need to be matched due to spline count. A little thing that even I forget every now and again when grabbing stub axles off the shelf to move a car around. Or changing out the run hubs to have hub centric rears.

Conversations about ball joints, and pinch verses wedge , and that also includes the struts.

In the long run we have not gotten to the real reason. It is easier to know that when you go to the parts place of choice and your looking for a front suspension part you do not need to know the part number. You just need to know the year and donor vehicle.

I have ruined that idea on my builds borrowing across parts bins from various manufactures, and suppliers. Like you Alfa brakes up front on a 914/6 front strut 3" bolt pattern for caliper mounting. 914-6 A-arms, 911 torsion bars out of a 1988 Carrera, with a set of Bilstein inserts in a Boge body that has had the spindles raised.

Sometime simple is better

914 A-arms with full motion bearings with custom made seals, 914/6 struts, alfa brembo Al calipers, bilstein struts, turbo tie rods, stock sway bar (for now),

Nice custom seals!!!
Any chance you have an extra set up f seals for sale?

Nice custom seals!!!
Any chance you have an extra set of seals for sale?

I'll have to check my notes, the one seal (pictured) is a VW bug front beam torsion bar seal, the other is also bug, but I can't remember which one.
That was 3-4 years ago.

And my point exactly, if you keep everyone 911 then it becomes simpler

I keep telling myself to build a book of parts for all my builds I never do it