Can anyone ID this GS1100 cyl head?

[maicojoe]

I bought this head used years ago, the owner was selling miscellaneous GS parts but had no information on this head, just that it had been street ported with oversized valves at 26mm x 28mm.
just wondering if anyone can tell me what year the head is, and if anyone has information on the outfit that ported this head..... " SPEED PRODUCTS" with the initials L.P.Z. and SGK #818.
Its used, so was thinking of getting it freshened up, new valves, guides, seats, springs, retainers, etc.
And putting it on my 1983 GS1100 with cams, pipe, carbs.
Thanks, JoeIMG_0115.jpgo

[maicojoe]

Pic #2

IMG_0119.jpg

Picture of porting, valve guides look cut down?

[mr wu]

I bought this head used years ago, the owner was selling miscellaneous GS parts but had no information on this head, just that it had been street ported with oversized valves at 26mm x 28mm.
just wondering if anyone can tell me what year the head is, and if anyone has information on the outfit that ported this head..... " SPEED PRODUCTS" with the initials L.P.Z. and SGK #818.
Its used, so was thinking of getting it freshened up, new valves, guides, seats, springs, retainers, etc.
And putting it on my 1983 GS1100 with cams, pipe, carbs.


Thanks, Joe[ATTACH=CONFIG]51935[/ATTACH]o

Dick Speed out of Illinois could probably answer your questions....

[maicojoe]

Thanks Mr Wu, that was the information I was looking for. Googled "Dick Speed", found a phone number, called it and Dick of Speed Products answered the phone himself. Very nice guy, answered a ton of questions, even looked up his records on this particular head. I will be shipping the head off to him, get it freshened up. It is pretty much like the seller told me, a very fast street/strip head. Dick did say the very same head has gone 144 mph and about 9.4 in the 1/4 mile, so should be a fun street bike for me. Anybody have a chart for 1/4 mile mph to rwhp factoring in bike and rider weight?