Help with engine differences Between 81 1100E & 1100EFE

[GSXRacer]

Hey Guys
This is my first time up, so i hope you can help.
I have a 81 GSX1100E that i have been building as a period 5 vintage superbike. I do have some nice parts on it, but i am looking at buying a spare motor for it so i can build up a spare monster engine for it without disturbing my current one till i'm ready.
I have come across a complete EFE engine with a couple of spare heads and another disassembled engine for a decent price.
My question is, i have to use a pre 83 bottom end to stay within the period 5 reg's, so will the EFE barrels and/or top end fit on the 81 cases?
While i have your attention can you also tell me if there is any differences between the mounting points on the bottom end on the 2 engines?
It's a pretty sweet build actually, I mightn't beat those super expensive XR69 Replicas that are out there but i'm going to have a whole lot of fun trying.
cheers.

[ozman]

Hey Guys
This is my first time up, so i hope you can help.
I have a 81 GSX1100E that i have been building as a period 5 vintage superbike. I do have some nice parts on it, but i am looking at buying a spare motor for it so i can build up a spare monster engine for it without disturbing my current one till i'm ready.
I have come across a complete EFE engine with a couple of spare heads and another disassembled engine for a decent price.
My question is, i have to use a pre 83 bottom end to stay within the period 5 reg's, so will the EFE barrels and/or top end fit on the 81 cases?
While i have your attention can you also tell me if there is any differences between the mounting points on the bottom end on the 2 engines?
It's a pretty sweet build actually, I mightn't beat those super expensive XR69 Replicas that are out there but i'm going to have a whole lot of fun trying.
cheers.

you cannot run the efe head the rocker cover gives away the fact its a 84 motor and the cutoff date is dec 82

ozman

[chef1366]

The barrels bolt right on but the pistons do not. You can get an 1100 piston kit to use the same crank and boost some CCs.
The wrist pins on the early 1100s are 18mm and the efe is 20mm.
You can do this and use the early head so you don't tell on yourself.

[GSXRacer]

Thanks guys, looks like i will have to keep looking.
On another note do you have any experience on what is a good road race grind cam for my 81 1100E motor? I have a 1166 wiseco kit and a very well ported head with stainless O/S valves and i'm running a big bore Yoshi exhaust with it.
Lots of info for drag use but not much info for road race use.
Anyone have any suggestions on what works well?

[ozman]

Thanks guys, looks like i will have to keep looking.
On another note do you have any experience on what is a good road race grind cam for my 81 1100E motor? I have a 1166 wiseco kit and a very well ported head with stainless O/S valves and i'm running a big bore Yoshi exhaust with it.
Lots of info for drag use but not much info for road race use.
Anyone have any suggestions on what works well?

give mick dewitt a ring he does my dyno work preety good on the cam setups to
he is at monbulk in melbourne

DEWITT MOTOSPORT
0408397799