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Ductech
So after jacking up the front end and looking around i noticed that the two pieces of strap steel that go back from the torsion housing. their should be two bolts there. One on each strap. I worked up auto atlanta's site and found the part in question. they list as such 900 075 040 02 Hexagon-Head Bolt M 10 X 20 so if im not totally retarded that a 10 mm shank, and it is 20mm long. but what is the thread pitch is my real question. cause i would like to go to a hardware store instead of ordering it over the net and waiting.

Thanks for helping with mid day retardedness
SirAndy
QUOTE(Ductech @ May 16 2011, 12:06 PM) *
why would the PO do this?

There's a belly pan mounted there that one has to take off to get to the steering rack and master cylinder etc.
Someone took that off and forgot to put it back on. I've seen that happen more than once.


Driving without those bolts is dangerous! blink.gif
Ductech
QUOTE(SirAndy @ May 16 2011, 12:25 PM) *

QUOTE(Ductech @ May 16 2011, 12:06 PM) *
why would the PO do this?

There's a belly pan mounted there that one has to take off to get to the steering rack and master cylinder etc.
Someone took that off and forgot to put it back on. I've seen that happen more than once.


Driving without those bolts is dangerous! blink.gif


I agree I'm now very glad that Iv'e only been mobbing around the neighborhood. haven't really hit the freeway

any takers on what the threadpitch of the bolt is ?
poorsche914
QUOTE(Ductech @ May 16 2011, 03:06 PM) *
So after jacking up the front end and looking around i noticed that the two pieces of strap steel that go back from the torsion housing. their should be two bolts there.

I found the same thing on my LE. Luckily, I had a parts car to pull the bolts from.
Sorry, I don't have info on pitch, etc.


driving.gif
Cap'n Krusty
Since no one else has bothered to answer your question, here it goes. Nearly all 10mm fasteners on Porsche and VW vehicles have a 1.5 thread pitch, and these are no exception.

The Cap'n
SirAndy
QUOTE(Cap'n Krusty @ May 16 2011, 01:05 PM) *
Since no one else has bothered to answer your question, here it goes.

I didn't "bother" since i didn't know the correct answer. I know, that's not really how we usually do things around here, but hey, i guess i was in the mood of bumping this thread until someone krusty would come along with the right (?) answer ...

laugh.gif
windforfun
I replaced my belly pan & rubber seals with restored parts. Not all pans are interchangeable from year-to-year. FYI.

type.gif type.gif type.gif
enderw88
QUOTE(Ductech @ May 16 2011, 11:06 AM) *

but what is the thread pitch is my real question.


I highly recommend buying a thread pitch gauge like this one from amazon. I have both metric and SAE and they are worth their weight in platinum for exactly the reason you just discovered.
Ductech
Thanks Capn I knew a guru from here would know why they(porsche) didn't label the pitch of said bolt, I figured it was because their was a standard that they adhered to.

I'll go run and grab some today
sww914
Almost every thing on these cars is either 6X1, 8X1.25, or 10X1.5. You can see the progression, it's easy to remember like that.
balljoint
I have a great thread pitch gauge and bolt size gauge and thread cleaner all in one. It's made by a company called Tap & Die.
jaxdream
While we are on the subject of suspension bolts , particulerly the front , why did Porsche chose to to use 8.8 WTF.gif hardness rather than a harder / stronger bolt ??? I have noticed this on the few that I have dismantled .

Jack / Jaxdream
Bartlett 914
Do not jump to conclusions about standard and fine threads. There are both on the 914. One of the bolts in question is a fine thread. The short bolt that goes to the right and also holds on the belly pan is a 10 X 1.5 screw. The longer one on the left uses a 12 X 1.5 which is a fine thread. A standard 12 mm bolt is 12 X 1.75. There are others in the 914. The brake calipers are held in place by fine thread screws also. I am sure there are others.
Cap'n Krusty
QUOTE(Bartlett 914 @ May 17 2011, 07:42 AM) *

Do not jump to conclusions about standard and fine threads. There are both on the 914. One of the bolts in question is a fine thread. The short bolt that goes to the right and also holds on the belly pan is a 10 X 1.5 screw. The longer one on the left uses a 12 X 1.5 which is a fine thread. A standard 12 mm bolt is 12 X 1.75. There are others in the 914. The brake calipers are held in place by fine thread screws also. I am sure there are others.


I beg to differ with you. 12X1.25 is fine. 12x 1.75 is coarse, and you won't find it anywhere on a Porsche. 12x 1.5 is found all over our cars. Japanese cars use 10x1.25 and 12x1.25 in most applications. 12.175 is used in some VW and Audi bell housing applications, but not many other places.

The Cap'n
ArtechnikA
QUOTE(jaxdream @ May 17 2011, 10:12 AM) *

While we are on the subject of suspension bolts , particulerly the front , why did Porsche chose to to use 8.8 hardness rather than a harder / stronger bolt ?

Because you pay a price for the increased hardness (not needed in this application) and tensile strength (not needed in this application - it is primarily a shear load...).

8,8's will bend in an impact. 10,9 is more brittle.

When you hit something hard enough to damage the fastener, it should still hold stuff together. Bolts that break in the initial impact tend to shed whatever they were fastening setting you up for a bigger secondary impact.

This is why you see SAE Grade 5 or, better, AN, hardware in race cars that use SAE stuff - and never Grade 8.
jaxdream
QUOTE(ArtechnikA @ May 19 2011, 03:23 AM) *

QUOTE(jaxdream @ May 17 2011, 10:12 AM) *

While we are on the subject of suspension bolts , particulerly the front , why did Porsche chose to to use 8.8 hardness rather than a harder / stronger bolt ?

Because you pay a price for the increased hardness (not needed in this application) and tensile strength (not needed in this application - it is primarily a shear load...).

8,8's will bend in an impact. 10,9 is more brittle.

When you hit something hard enough to damage the fastener, it should still hold stuff together. Bolts that break in the initial impact tend to shed whatever they were fastening setting you up for a bigger secondary impact.

This is why you see SAE Grade 5 or, better, AN, hardware in race cars that use SAE stuff - and never Grade 8.


Ok , that makes perfect sence . Engineering specs .

Jack
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