- Posts: 443
- Thank you received: 36
81 and 84 GPZ1100 cylinder head comparisons
- barney
- Topic Author
- Offline
- User
Please Log in or Create an account to join the conversation.
- oldkaws4ever
- Offline
- User
- Have no regrets...... You only live once.
- Posts: 1648
- Thank you received: 12
74 Z1a 900 (Apart and making it better than ever)
77 Kz 650b (Threw a rod, going to sandwich in a 900 or 1000 motor)
76 Kz 400d
05 ninja zx-636
81 Kz 750 Ltd
Darien, Illinois
Please Log in or Create an account to join the conversation.
- PLUMMEN
- Offline
- User
- Posts: 8139
- Thank you received: 104
Still recovering,some days are better than others.
Please Log in or Create an account to join the conversation.
- Mcdroid
- Offline
- User
- Gone Kwackers
- Posts: 6634
- Thank you received: 317
Michael
Victoria, Texas
1982 GPz750
1977 KZ1000A
1978 KZ1000A
1982 GPz1100
1975 Z2A
Please Log in or Create an account to join the conversation.
- timebomb33
- Offline
- User
- Posts: 4288
- Thank you received: 10
1973 z1 2-1974z1-a,2-1975z1-b dragbikes1015cc+1393cc, 1977kz1000,1978kz1000,1981kz1000j, 1997 zx-11, 2000 z12r,1428turbo nitrous pro-mod and a shit load of parts thats all for now leader sask.,CANADA
I THINK MY POWERBAND BROKE
Please Log in or Create an account to join the conversation.
- PLUMMEN
- Offline
- User
- Posts: 8139
- Thank you received: 104
slow down youre making my head spin here!:laugh: you can use the 81-82 gpz/81-90 something j head on the old motors depending on which path ya wanna follow.you can just run higher compression kz pistons knowing its going to drop around 2 full points depending on who you ask,or you can use j pistons on the stock kz rods with a spacer under the cylinder to make up for the kz rods.either way you need the cam chain adaptor to make it work.the 83-84 gpz also uses bigger wrist pins so its really cost prohibitive unless you have really deep pockets to make that one work,ive got some 83-84 kz/gpz 1100/1170 pistons someplace that i learned this on the hard way!:laugh:in order to run the late model gpz head you have to use j rods on the crank as they are .40" shorter [pin heights are different from kz to gpz pistons] and since the combustion chamber is larger you will have to get pistons made up to fit the gpz head or you won't have any compression.
Still recovering,some days are better than others.
Please Log in or Create an account to join the conversation.
- barney
- Topic Author
- Offline
- User
- Posts: 443
- Thank you received: 36
Im running a 1981 GPZ motor in my ELR(my head has the injector ports in the head- I've already blocked them off and am running carbs).Motor runns great. Problem is , I have a small crack across one of the cam plug holes. I know of a nice 1984 GPZ 1100 head for sale and was wondering if I could just drop it on my 81 J motor .
Please Log in or Create an account to join the conversation.
- PLUMMEN
- Offline
- User
- Posts: 8139
- Thank you received: 104
Still recovering,some days are better than others.
Please Log in or Create an account to join the conversation.
- barney
- Topic Author
- Offline
- User
- Posts: 443
- Thank you received: 36
Please Log in or Create an account to join the conversation.
- PLUMMEN
- Offline
- User
- Posts: 8139
- Thank you received: 104
Still recovering,some days are better than others.
Please Log in or Create an account to join the conversation.
- steell
- Offline
- User
Sorry I didnt explain clearly enough
Im running a 1981 GPZ motor in my ELR(my head has the injector ports in the head- I've already blocked them off and am running carbs).Motor runns great. Problem is , I have a small crack across one of the cam plug holes. I know of a nice 1984 GPZ 1100 head for sale and was wondering if I could just drop it on my 81 J motor .
Why don't you ask Larry Cavan (user name)? Since he does this stuff for a living I'm inclined to think he knows what he's talking about.
Cavanaugh Racing Heads
www.flowbenchtech.com/porting/CRH/index.htm
KD9JUR
Please Log in or Create an account to join the conversation.
- APE Jay
- Offline
- Banned
- Posts: 1403
- Thank you received: 58
Not too sure about volume differences, but the shape would mean aftermarket pistons for the early head, might have to be modified to clear the late chamber.
No connecting rods have to be changed.
Jay
Please Log in or Create an account to join the conversation.