Rambino

Just Curious if anyone knows who makes good strut towers for a 1989 944 "Turbo S" such as that of Racing Dynamics. ??

Thanks

IceShark

If you are going to a strut brace, may as well go all the way and get one that attaches to all four tower bolts, as in a hat type. I believe the Racing Dynamics one only attaches to the first two shock studs. And doesn't stiffen up the whole affair as well as others.

The Weltmeister fits the bill and clears the hood. Only problem is the gold anodizing will rust after a few years. I've had mine for quite a few years and went and had the whole thing chromed due to the rust. That was another 100 bucks.

Don't worry about weight, it is under 4 pounds.

It really does stiffen the car up, even in normal street use. Of all the improvements I've made that was second best, for the buck, behind headlight rewiring. Well, at least until I had to have the thing chromed. -g-

This is on an '88 951S.

Skip

The best is Brey-Krause...

Attaches to 3 bolts at each strut tower (very sufficient), is stainless steel, and is adjustable for preload.



Weltmeister is certainly very efficient also.

Good Luck!

Macabre

Why would it matter how many bolts it attached to? Seems like two would be plenty. You're only trying to stop compression/extension stresses and not torsional stresses. Have you heard of anyone shearing the bolts off with only two used?

IceShark

Skip, I think the Welt is the way to go, only problem is the rust issue. And stainless will also rust, BTW. A couple of engineers looked at this on the old Rennlist and really liked the design v. the others. If Welt would put it out in stainless there would be no further questions on which is the best.

I wound up chroming mine. Which turned out to be an unpleasant experience for everyone as they didn't clean off the polishing crap and the plating couldn't get at the base metal in some spots. All fixed, but no one was happyb about it.

IceShark

Mac, because the whole tower is suspect so it is nice to have the additional full hat material reinforcing it. I don't have an engineering degree, but I have to agree with those that want a full hat.

Macabre

What is suspect about the tower?

IceShark

Suspect to flex. And it isn't suspect, it is a convicted felon in that area.

Macabre

I don't get it.. what does the number of bolts you mount too have to do with flexing? (I'm asking because I plan to build my own strut tower bar, and can just as easily build one that mounts to all four positions as opposed to two if there is a reason to do so)

IceShark

The number of bolts ain't the particular issue. It is more about beefing up the sheetmetal with the hat. Jeez, this is a well known problem that I thought was settled. Guess we need a better FAQ.

Skip

Are we talking about the upper strut mounting area ripping apart? You've seen that? Curious... I would think the most applicable advantage of 3 or 4 bolts would be quite different, and to just provide a steady mechanism for the bar itself to mount to without twisting. The Welt unit is certainly a very capable and popular piece, but there are a few items that are improved by Brey-Krause. One is the SS... won't rust. The other is the hats... they're a bit cumbersome when using adjustable camber plates (a staple for racers who would be using the strut brace for competition)

The specific function of the strut bar is to box the front suspension and create a semi-rigid force against the deflection of the strut tower. A 2-point mount works okay at this, but 3 or even 4 would be better (not bolts, but mounts). The problem there is mounting positions and class rules. Most GCR's only allow two points for mounting... otherwise it's classed with tube-frame type cars that would normally tie the strut tower together as part of the saftey cage. The 2 point mounting of the popular strut braces is sufficient until the car is out of class anyway. For those who don't follow, the 2 point mount actually causes the whole suspension to shift from side to side with extreme motion... but it takes a heck of a lot more force to get into any trouble with unwanted camber changes due to it. One of those "you can't get there from here" things

That said, I have seen some of the import tuner folks run into ripping metal hats when using the cheasy aluminum and weak steel mounts so popular for "show". I just can't imagine the stamped steel strut tops ripping apart, unless installed wrong, or given too much preload.

Skip

Macabre

Thanks, Skip. I guess I'll stick with two as I had originally planned.

aka 951

From this mechanical engineer's perspective the welt. is the better piece because it evenly distibutes the force thoughout the entire strut tower, instead of merely to two or three bolts. Of course I made this decision AFTER I bent both strut towers on the street. Nice design Porsche, or should I say Audi! These cars are real flexi-fliers when you tighten the suspension up!

The 2 bolt strut braces look nice but I think they are crap and mainly for show. Yes, they may help in compression but they're still exerting all the force through only two tiny bolts on top of each strut tower. Personally, I don't like to screw around and that's why i went with the welts. Everything weltmeister seems to make is overbuilt and thats why I like their stuff. Haven't had any rust issues either, but that's probably because I live in So Cal.

On the other hand if you don't have upgraded springs or shocks and don't race the car, these things are completely useless.

Skip

Whoa... 2 bolts isn't enough... I didn't mean to give that impression. 2 points are plenty... if that's what you meant.

The discussion was the difference between 3 and 4 bolts (BK = 3, Welt = 4). Unless someone has a specific example of BK failure (or other 3 bolt) then I would suggest that is enough. Remember also that the top mounting of the strut bar carries through to the under mounting of the spring collar. That's two flat pieces of steel that are ridge bent (for stiffness). And, if you look at the way the load is distributed, it goes lateral to the bolts... making the possibility of them ripping up really hard to imagine... they would have to shear off the mounting studs from the lateral compression force.

Skip

ksc jc

Have any of you uprated the strut mounting
rubber to MO specs type ? They are harder &
would probably perform better than strut tower for street use. In my opinion, instead
of strengthening the front, you guys should
actually look onto strengthening the rears
first. Now there just to much flex in the rear compared to the front.