[Kreylyn]

But it just cant be the carbs and the cams that makes the gsxr much more powerful. The 89 gsxr 750 is rated at 112hp and the post 750 Kats are only 93, which are basically the same motor. The compression is the same and different gearing should make the power change that much

ancient thread aside...

The 89 750 GSXR and the PRE 750 (89-97) kats are what is near the same engine and put out near the same power. A cam change did put you much closer.

In 98 the 750 engines bore and stroke were changed to match the later model GSX
R oil cooled engines. There is a noticeable difference between the pre kat engines and the post kat engines in performance. Other than Cams and carbs... I don't know of a difference between the 92 GSXR engine performance wise vs the Post Kat engines. So cams and carbs could possibly make a huge difference, especially when your looking at a bike that is seriously "detuned".

Krey

[gsxr750]

Head Swap

Will the Head off a 1987 GSXR 750 work on a1990 Gsx750

[Cheap Bass Turd]

I think so on the heads. The block has changed very little if at all on the outside.
Suzook got that one right long ago.
Ya don't see too many blown GSX engines of any cc or vintage.

The cam chain/ head gasket and oil holes should all line up.

[92xjunker]

Get the cams for it also. Big difference in power.

[92xjunker]

Will the Head off a 1987 GSXR 750 work on a1990 Gsx750

Absolutely basically the same engine.