Button Head Bolt / ARP Bolt / Irs Sub Frame

[Black2003Cobra]

OK. I measured the height of the head on one of the button head bolts that many of us got from Jayson. It is roughly 6.5 - 7 mm (0.256 - 0.276 in) high. Pretty much the same number that toofast measured. I recall seeing a pic of these installed and the guy used a washer behind it, also. So if these ARP fasteners come out to 0.3", they'ld probably work just fine. (I assume they won't require a washer behind the head?)

:beer:

 

[Cobra'03]

Originally posted by Fiveohdean
You have to consider that Stress = load/area. By decreasing the cross sectional area available to support the torque load the stress at the fastener head has increased. ARP will properly evaluate this and only provide a bolt that is adequate.



Not necessarily. The increased stress will decrease the fatigue life of the fastener. And if it fails going into turn 9 at Willow Springs you'll wish you waited for the ARP fasteners!




Black2003Cobra,

Your comments are correct. My point is anything that can affect the safety of the car has to be taken seriously. There's a significant difference between these two bolts. I wouldn't use anything that wasn't evaluated properly. A profesional buisness such as ARP has this capability and will give us the correct anwser one way or another. In 13 years of road racing I've had 4 mechanical failures. Three of which were quite expensive. All of these failures could of been prevented If I would have spent another 100 dollars on the car. The piece of mind will be worth a few extra bucks.

I agree with both the engineering analysis and the practical one - I would be very careful in messing with suspension bolts, as the dangers of failure are high. I worked on NSX's for a while, and had one that got all squirelly in its handling, as these cars had very odd toe in settings and precisision aluminum rear suspensions. After a lot of measuring and thinking, I looked at the lower arm bolts and determined that for some reason they had been removed and re-used. Honda was very specific about the bolts , and that they should not be re-used. In some cases, the bolts actually stretch under load to ensure they maintain the design spec in real use. ARP factors this into their specs and application recommendations - this is very much the case in head bolt design for example, as the amount of "land" between thread and head can be critical.

 

[Hunter]

Originally posted by Black2003Cobra
I recall seeing a pic of these installed and the guy used a washer behind it, also.

Yea, that was me.

 

[ALLNTRL]

Bosko go ahead and put me down for 1 set of the ARP's.

Thanks :beer:

 

[Black2003Cobra]

Hey Bosko - any new info?

 

[Bosko]

Sorry guys... No new info... I called him yesterday 2 times and left messages and called him today. He was unable to talk to me... Im going to call him tommarrow. Im starting to get frustrated. Ohh... Ill update the list in the next day or two for thoes of you who want bolts.

 

[Hunter]

Thanks for the info. Keep us updated.

 

[jonas]

bringing this thread back to life

 

[lebda]

Why?
Bosko has already clarified that they are not willing to do the bolts on another thread. (if I am not mistaken)

 

[MidLifeC]

How about this idea?

AT the SVT HQ tour, I asked about tire sizes and clearances. One engineer suggested the '00R had the same clearance problem, and Ford already built a buttonehead bolt that should drop right in for us.

Anyone care to check with an '00R owner?

 

[ricks03cobra]

:shrug: Does this mean we do not have a solution to the bolt problem?

 

[JKD COBRA]

count me in. I will take a set.

 

[jonas]

me 2

 

[Poisonous Mods]

See pic.... 18x10.5" AFS on 295 x 35 x 18 Kuhmo's.

http://svtperformance.com/forums/showthread.php?s=&threadid=45076

Cant post the pic twice :bash:

 

[ricks03cobra]

I will take 1 or 2 sets

 

[ac427cobra]

Hey Gang:

Sorry for resurrecting this thread but I can't find anywhere if buttonhead bolts for the IRS were ever found?

I'm trying to fit ASF 18 x 10.5" wide rims on the rear of my "R" and am having a clearance issue on the left side.

I have ground about half of the bolt head off on the right and feel comfortable with the clearance I have on that side. The left side is much tighter and I have ground off more than half of the head and don't feel comfortable grinding any more off. I have about 1/16" (or less) clearance on the left in the completely unsprung condition. I'm not sure if this is going to be enough? My car is primarily a track car and won't be on the track anytime soon unfortunately.

I would greatly appreciate any info anyone can supply!

Thanks,

:thumbsup: :coolman: :beer:

 

[toofast4u]

Originally posted by ac427cobra
Sorry for resurrecting this thread but I can't find anywhere if buttonhead bolts for the IRS were ever found?

No. The only button head bolts found are not recommend for use as they are fully threaded and don't have shoulders like the stock bolts.

 

[ac427cobra]

Originally posted by toofast4u
No. The only button head bolts found are not recommend for use as they are fully threaded and don't have shoulders like the stock bolts.

Tanks!!:thumbsup: :coolman: :beer:

 

[Black2003Cobra]

Yes, just as toofast said, the ones that are threaded all the way up have failed on some folks. Quite some time ago, AFS had some with shoulders on them that they had gotten from one of their customers (Randy). I doubt they have any left, but I'm sure someone could find them somewhere if they looked hard enough. What several people have done instead, is just grind down the head a bit on the stock bolts to get adequate clearance. (AKA, the Undy bolt mod.)