Topic: How hard would this be?

[Smowkin Joe]

How difficult would it be to get a GX390 to rev to 8,000 rpm with stock size valve seats?

[Sherman Underwood]

How difficult would it be to get a GX390 to rev to 8,000 rpm with stock size valve seats?

I know of a couple... Hint.... lots of port work and very good cam profile, I wont reveal everything . I will say this, there is a big difference in a motor that will rev to 8000 and one that makes power all the way to 8000....!!

[George Herrin]

Anything above 7200 and your flirting with blowing the jug off. But yes they will do it and if done right make hp there. But its not a drop parts in kinda build.

[Smowkin Joe]

Thanks guys. I didn't think it would be simple, but at the same time knew there had to be more than one individual that has done it.

[cubcadet70]

It will take some special attention to the head and the valvestrain. I would put a Isky cam in it and of course... Some billet parts on the inside! 

[FXS 49]

I was  turning 8000 all year on our clones and 8200 at some tracks. We have 3 built and havent lost a part yet.  Its a combination of stuff.  Research and see just where you want your power band,,  Cam, port work, Carb. 

[George Herrin]

Precision cams built Jakes motors, Jake did his own carbs both HR's, but those that have seen Jake run well it speaks for itself. Want a screamer call Mike @ Precision Cams. They pretty slick on them 390/420 motors be it honda or clone motors.