The previous owner of Gus (my 85 GS) used these two bolts to connect the engine to the transmission. After much confusion I realized that they weren't the correct bolts. Which begs the question, where did he get these two bolts from? Did he rob them from someplace else on the car? Here are the specs....

M10 X 1.25
45mm long
Lockwasher on each bolt
"7" stamped on the head

Anybody have any idea where these things are SUPPOSED to go? Just want to make sure that the previous owner didn't do something totally boneheaded / dangerous.

Jamie

 

I'm guessing Buick or MG. I haven't seen those #7's on my RX-7s.

The rounded edges suggest that metric tools have been used on British bolts.

 

The 7 should be a strength grade. Anything below an 8.8 is usually not hardened & tempered. I've never seen a spec grade 7, though.

 

So are we safe to assume that these bolts don't belong ANYWHERE on an FB? I figured he stole them from someplace else on the car. Never thought that they didn't even belong in the first place.

 

Possibly lost the trans to engine bolts and just had those lying around the garage/toolbox so he tossed them in instead of finding the right bolts. I have a ton of bolts in the bottom of my toolbox that i sift through every now and then if I need one.

 

Bolts is bolts... if they worked, who cares?

The only oddball bolt on an RX-7 is the lower starter bolt. It's a 10x1.50 and not a 10x1.25 like everywhere else.

The only other makes to use 10x1.25 are Toyota, Subaru, and Nissan. I'd guess that those are Subaru engine to trans bolts, since Subaru likes to use non-necked bolts.

 

Metric specs are n.n, like 4.8, 8.8, 12.9. You won't see a single number.