GS1000 rebuild opinion

[koolaid_kid]

Good link, John Kat.

GregT, I stand corrected. Never heard it called that, milling the head is more commonly used. And yes, I am extremely aware of the process, having 4 decades of racing experience.

[mrl1000l]

Here you go: Degreeing those cams
If you notice, the names I suggested you contact about your engine build participated in these threads.

This is great, the link in that thread that takes you further down the rabbit hole is where the meat of the degree article is. Koolaid, how many degrees off are cams from factory? just curious.

You say tomato, I say well....The head machining is not generally done on a mill. Like decking the block, it's done on a surface grinder.

Greg, I have a favor from a friend with a mill, I will likely get my cylinder milled by him. I didn't realize that decking involved a surface grinder.

Here's the thread that covers the subject in great detail
http://www.thegsresources.com/_forum...=cylinder+head

John, I have read and re-read this thread a few times. It's great, I'm using many parts of it as reference for my rebuild. The one thing that I'm confused on is it seems like srsupertrap uses 73.5mm GS1000 big bore pistons with the 1100 head, because he wanted the larger intake port and the D exhaust port, but wouldn't he be loosing compression ratio from this mixture or does he make up for the loss by decking head? Is this splitting hairs? This is why I'm exploring the option of retaining the small port GS1000 head.

[koolaid_kid]

This is great, the link in that thread that takes you further down the rabbit hole is where the meat of the degree article is. Koolaid, how many degrees off are cams from factory? just curious.

Yes, the link is the best part. Posplayr tends to be a perfectionist, but he does tell it like it is.
That is the issue, cam timing is indeterminate, subject to mass production inaccuracies. When you degree your cams yourself, you are spot on.

Greg, I have a favor from a friend with a mill, I will likely get my cylinder milled by him. I didn't realize that decking involved a surface grinder.

Not sure what you mean here. Decking the block and milling the head (I am using the more common terms) both require a surface grinder. It is a very large, flat, circular grinding wheel with very precise computer aided measurements. The block or the head is mounted in a jig, then slowly lowered into the grinding wheel. Again, the purpose of decking the block is to make it perfectly flat. The purpose of milling the head is to raise compression, although it also doubles in making it perfectly flat as well.

John, I have read and re-read this thread a few times. It's great, I'm using many parts of it as reference for my rebuild. The one thing that I'm confused on is it seems like srsupertrap uses 73.5mm GS1000 big bore pistons with the 1100 head, because he wanted the larger intake port and the D exhaust port, but wouldn't he be loosing compression ratio from this mixture or does he make up for the loss by decking head? Is this splitting hairs? This is why I'm exploring the option of retaining the small port GS1000 head.

Yes, you mill the head to raise the compression. It is generally preferred to go with the larger ports, and since you have the heads already, the choice should be easy.

[mrl1000l]

I think I understand, thanks for the clarification. I've got a lot of reading to do.