blade7

I did a search, but no answer really. So how much clearance between the fuel rail and the underside of a strut brace should there be?

333pg333

Never seen a strut brace with a lot of clearance but have also never read that there is a 'prescribed' clearance required. Having said that, I'm not really sure how much good they do?

Droops83

I agree here. My 1973 BMW 2002tii is the only car I own in which a strut brace makes an obvious difference, which is because it is a 1960s unibody design with the torsional rigidity of a noodle! That said, mine is set up to be a fast road rally car and is epic fun on tight and twisty and rutted backroads . . . .

The 924/944 is of course only a decade newer, but it is the next generation of unibody design, I cannot discern any difference with my 944 Turbo hatchback with or without strut tower brace. When I upgraded to Ground Control coilovers front and rear almost a decade ago, the top-mount camber plates came with a Ground Control-designed brace to span the engine bay, but it didn't clear the 951-specific heat shields, and I never took the time to modify the heat shields for it to fit. Never felt the need to do so.

However, the Brey-Krause lower chassis brace DOES make a huge difference in feel, even on the street. I have all spherical bearings for the suspension of my 951, and I always had the issue of the caster block/rear lower control arm bushings shifting with heavy braking during track use, despite new fasteners and constant re-torquing (they weren't designed for this sort of load), but this chassis brace completely eliminated the issue by spreading the load. I also have a 1990 944S2 Cabriolet as a street cruiser, strut tower brace made a tiny difference in that application, and I plan on getting a B-K lower chassis brace for that one as well, 944 open-top platform is a bit rubbery and jiggly!

https://www.bkauto.com/R_1524_Front_...8_p/r-1524.htm

blade7

Thanks for the replies. I've had one of those KLA strut braces fitted for years, and always thought the alloy bar wasn't that strong but should at least stop the turrets spreading. I looked at the Cup cars too, and decided Porsche wouldn't have bothered if their brace didn't work. Anyway I found there's not much clearance for the bar between the underside of the bonnet and the top of the fuel rail, and wondered how tight the more expensive alloy bars are. And if the engine could float on it's mounts a little on bumpy roads. I considered a lower chassis brace too, but didn't fancy putting extra load into the castor mount bolts, and the hassle to fix the mounts if the threads were damaged.

wildcat077

I've had two different strut braces on my SP2 car without interference issues, if they're specifically made for a 944 they should all fit.
By the way , they do work ... i took a major hit front left and it cracked the weld on the strut brace but i guess that's what the intended purpose is
as it probably saved the car from more extensive damage.

Cheers
Phil

V2Rocket

Not an easy thing to measure but anecdotal - if you have a strut brace installed with the car on the ground, and remove the brace before lifting the car up, you won't be able to reinstall the brace with the car in the air.
The body flexes enough under its own weight that the shock towers move relative to eachother. I imagine on a microscopic scale that kind of flex in a racing scenario might affect camber somewhat.

V2Rocket

on mine i recall about 8mm clearance to the fuel rail plastic cover with the KLA brace.

333pg333

When viewing the car from front on, I always pictured a parallelogram missing the bottom line when equipped just with a strut brace. But with the bottom chassis brace perhaps it would complete the shape (as such) and create a bit more of a tighter unit.

blade7

Some seem to think the engine crossmember ties the lower chassis rails together effectively. And a simple bar between the castor mounts is enough. The Brey Krause parts look pretty, but they seem like a 10 minute answer to a 1 minute question to me.

333pg333

I think it matters a lot more if you're on the track. On the street, not so much. Sure, the car will lose geometry under high twisting loads but it also depends on road surface, size of contact patch, grade of tyre softness, speed, situation blah blah...I'd guess most of the strut bars are pretty much the same. Running a cage up to the top mounts is worth it. Seam welding would help too.

blade7

I had one of these 80 V6's years ago. Audi must have thought it was worth fitting the sheet metal to bolt this skinny brace to.

blade7

Stronger than the original alloy KLA bar.


Tightens up the rear of the shell, a little.