81 gpz 550 83 550 swap

Hey i own an 81 gpz 550 but recently the motor got a bad knock, i have found a local craigslist add for a running 83 gpz 550 parts bike and plan to buy it for the motor and do a swap, any tips or suggestions or anything that may benfifit me in swap would be great to hear thanks!

That is the exact combination I have in my avatar bike.

The carbs will not directly swap. The newer motor has larger intake ports, and uses larger carb manifolds.

The older airbox won't connect up to the newer carbs without modification, and the newer airbox won't directly fit into the older frame.

So you will either have to modify the older intake manifolds and use the older carbs, or modify the airbox/boots to use the newer carbs, or use pod filters on the newer carbs. All are viable options.

I used the older carbs because I had several sets, and I installed pods which work great in that combination. Dynojet has kits for the newer carbs to run pods and many have reported that works well too.

To fit older intake manifolds to the newer engine, you have to slot the bolt holes to make them wider, then use thick washers tosecure them. I would recommend buying new ones since they will seal better to the head, since the old ones will have formed to the different size intake ports. Z1 Enterprises carries them.

Incidently, even though the motors appear different, internally they are the same except for the larger intake ports. Pistons, cams, trans, etc. are the same.

awesome thanks for the information, i already have pods filters on my current set up but i may try to just mont them on the new motor cause im not in the best financial situation , but i think i will eventually just swith the carbs thanks!!

new engine is in i just need to hook up carbs , exaust and coilwires and she should fire right up! will have pictures soon !