Author Topic: Would 11mm size bolts head fit on a 12mm block?? (Read 3582 times)

rabbit_diesel · « **on:** June 27, 2007, 09:51:12 pm »

I found a cylinder head for my 1.6 N/A block. It turns out that it is an 11mm head and I was wondering if I could some how make the 12mm bolts fit. The bolt holes are just a bit too small would it work to drill them larger? If so, how much larger should they be compared to the bolts?

saurkraut · « **Reply #1 on:** June 28, 2007, 05:46:09 am »

I'd be concerned about the compression ratio. Its probably a 1.5 head, which would have smaller swirl chambers. If you put it on a 1.6, your compression ratio will be higher, and thats not a good thing. By my rough calculation, the CR would be 25.3:1.

Does the Thorpedo still exist?

myke_w · « **Reply #2 on:** June 28, 2007, 07:26:55 am »

I've done it, works like a charm as long as it's a 1.6 head.
Just drill out the bolt holes with a large enough bit and do it with a drill press NOT WITH A HAND DRILL.

You'll need 12 mm bolts, and an extra 11mm head bolt washer per bolt.

The way to tell if if it's a 1.6 or 1.5 is the size of the oil drain bump on the front middle of the head.

small = 1.5

large (like your old one) = 1.6

rabbit_diesel · « **Reply #3 on:** June 28, 2007, 08:35:54 am »

Yes, I am sure it's from a 1.6 block. I'll make sure that I get them straight. So I will need two washers per bolt?

myke_w · « **Reply #4 on:** June 28, 2007, 10:51:43 am »

correct, 2 washers per bolt, you may need to grind the edges to get them to fit too. Let us know how it turns out.

tylernt · « **Reply #5 on:** June 28, 2007, 07:22:11 pm »

http://forums.vwvortex.com/zerothread?id=3116475

rabbit_diesel · « **Reply #6 on:** June 28, 2007, 07:47:02 pm »

Thanks Tylernt, that is good information! Especially on this Exact topic. :wink:

rabbit_diesel · « **Reply #7 on:** June 29, 2007, 11:29:17 am »

Quote from: saurkraut

Does the Thorpedo still exist?

Yes, it is still around. I was actually thinking of getting their vegetable oil to run in my jetta :lol: . Have you ever been there?