Arm support-2nd subject & 2nd thread

[captjm]

2nd subject and 2nd thread-

So what about strengthening the arm support, what can be done to do this on the 914?

[GreenWater]

I am interested in this too. I have already boxed the arm, which makes since to me, now I would like to strengthen the mounts.

[Brant]

this is not necessary on a street car.
but there are literally 20 different ways to brace the suspension console.

Here is a couple of shots on my race car. I used aluminum struts that are bolt in. My outboard bar is only a toe brace and is more pertinent for securing alignment settings than it is a suspension brace. The inboard brace is the one that matters. Check out my whole thread if you want more pictures:

[captjm]

Brant, are these arms a way of adjusting wheel alignment as well, or are they primarily for strength and support? Can you explain the race track thinking on the goal of 914 suspension. I get the grip the road and go fast idea, its the how to grip the road concept that is the mystery.

[Bleyseng]

A limited slip helps get more grip as both wheels are powered.
Tire size is important for grip, "wider is more tire footprint".
Alignment is important
Strenghtening the A- arms when you race with high lateral forces

For street all the stock stuff is fine until you push 250hp thru the wheels

[Brant]

Originally posted by captjm
Brant, are these arms a way of adjusting wheel alignment as well, or are they primarily for strength and support? Can you explain the race track thinking on the goal of 914 suspension. I get the grip the road and go fast idea, its the how to grip the road concept that is the mystery.

The inboard brace is purely for support.
I had a car that was PCA DE back in 1993 with a pretty stock 4 cylinder and 205 yokahama R's (old school d.o.t. tires)

I ripped out a suspension console one day on track.
replaced it although it was NOT rusty.
within 12 months and about 6 events, I ripped out the replacement.

I feel that the inboard suspension console bracing is important on any track car with a tire of 100 or lower tread wear rating.
NOT necessary for street.

I drove the same car on the street for 10+ hard years with NO problems.


the outboard brace is largely (but not entirely) for alignment.
with the bend in the arm, and the movement in the alignment bolts, a stock car changes toe setting under RACE conditions.
again NOT necessary or even discernable on the street.

but in theory it maintains your toe settings on the race track through range of motion and through G'load in a corner.

[rfuerst911sc]

The outboard brace shown in the last pic how is it attached to the long? Does the bolt go all the way thru the long and a nut and backing plate is on the inside? And where do you purchase those turn buckle type rods? Thanks

[J P Stein]

I haven't broken anything in the chassis or suspension. The whole chassis has been seam welded and thus far that has sufficed.

The inner ears are a weak point.
The factory welding around there is God awful....to include the spot welding. The spot welds often break over the egde of the pinch seams leavind a stress point for crack to start....nice. Seal welding these outside edges (and grinding them smooth) seems to have done the trick on these ears and the longs, but I fear the time will come when these will fail.

I have yet to have a toe change that would require me to go to the lengths that Brant has.....again, not to say it won't happen.

[Brant]

Originally posted by rfuerst911sc
The outboard brace shown in the last pic how is it attached to the long? Does the bolt go all the way thru the long and a nut and backing plate is on the inside? And where do you purchase those turn buckle type rods? Thanks

the attachment to the long does go all the way through, with welds on both sides.

bars and ends come from race shops.
I think these were hoerr racing, but speedway and other race shops sell similar.