Potential 5S-FE Rod Bolt replacements? Options

[Syaoran]

I've been searching all over the place for the thread pitch for the 7A-FE rods, since they are a cap-screw design rather than a pass-through like the 5S-FE is stock.

However, I can confirm that an M9 tap (1.00 or 1.25) will work on the stock bolt holes with the studs/bolts removed.



That is the upper portion of the rod tapped with an M9x1.00 tap. No drilling was done and the tap was a tight enough fit. It's already tapped halfway down the hole holding both the tap and the rod with my hands. With a vice and an oil squirt gun it'd be a lot easier but I have neither.

I don't know if anybody has ever done this before to a rod and I don't know if it'll actually work, but this is as far as I've gone up until now. Next I need a 7A-FE rod bolt to see if the pitch is M9x1.00. If not, I'll get the correct tap and tap another rod I have lying around and see how well it'll all fit.

It seems promising since, if the 7AFE rod bolt fits, 5S-FE rods could be modified to fit ARP Renault Clio 16V rod bolts, as shown here: http://www.6gc.net/forums/index.php?showto...view=getnewpost

What do you think?

[Syaoran]

All that would be left remaining is a custom pin setup to locate the rod caps. Shouldn't cost much from a local machine shop.

[Hafkai]

...Next I need a 7A-FE rod bolt to see if the pitch is M9x1.00....

I just measured one and it seems that M9x1.00 is correct

[Syaoran]

Thanks. I recently confirmed it with Summit Racing.

The Clio 16v kit is m9x1.00 1.6"uhl. All that remains is testing how viable it is to machine some kind of guide pin on the rods.


Something like this:



This post has been edited by Syaoran: Jan 25, 2014 - 9:28 PM