Team MightyBoy

I'd like to get an idea of how hard people's f8b's rev (usefully) and also if anyone has changed cams of one of these suckers (new or reground). The reason I'm curious about this is because I'd imagine the duration of a standard cam would be aimed towards economy and hence a performance upgrade of the f8b would be limited by this.

Finally, I'd imagine there'd be scope to increase valve sizes etc for the f8b head. Is this correct?

My F8B (bored, stock cam, weber, extractors) produces power up to just over 6k on the rocket clock, at which point it sings but doesn't provide any extra pull. I have the shift light set at 6.

Chris (MYD80Y) put a reground cam in his F8B, but it wasn't tuned and only really made it rougher at idle because of this. Of course a reground cam only modifies the duration of lift and not the height, for that you would need a custom billet cam.
In either case you need a vernier cam gear to take full advantage of a different cam. Adjusting the ignition timing will help, but a vernier gear is the best.

I'll reserve comments on valve sizes to Colin, suffice to say that porting the head would have more merit than messing with valves.

on a small motor dont go too big with valves ...it slows down the air speed making it rev up slower as for revs a simple indication i don't rely on my tacho 3rd gear f8 box i take mine to 110k/mh conservitavly

I've got a standard suzuki hatch with f8b and just jetted the carby and made the mechanical link for the secondary. It will sing all the way up to 6k mark on my charade tacho of course i don't take it any further, and only every now and then. It seems to cope with it quite fine. My motor's done about 170k and I keep it maintained, hope this helps you!

As for mods, the ones I've done as mentioned above are good value! Cost me all of about 30bucks! Made the car seem like its power had doubled!

i know this is an old post, but what will a F8B 4spd manual rev at 100kms?

If it has an F8B gearbox - 4000RPM

i heard of something today called ceramic coating... it might do the job... basically they coat your block/pistons/valves with a high impact ceramic... since ceramics are thermal insulators so you might be able to get a bit more bang

Does this mean that no-one else has heard a mightyboy motor at 9000rpm's?

My early weber-fed F5a one used to rip up to that.

No wonder it was a bit smokey at the end...

Hey Josh... You still got that head I gave you at Tarago? Might pay to have that checked to see if it had anything "done" to it
Always was a little suss on it. Why else would an F5 have forged slugs & ping like sh*t on anything less than AVGAS? Beating excels also should have rung alarm bells but I never heard them for laughing so hard

Yeah Adam, I've still got it. It's still safely nestled in an old cloth in my garage. Might have to get Colin to take a gander at it sometime.

Brayden wrote: Chris (MYD80Y) put a reground cam in his F8B, but it wasn't tuned and only really made it rougher at idle because of this. Of course a reground cam only modifies the duration of lift and not the height, for that you would need a custom billet cam.

Why cant you increase the lift with a reground cam?
I've had several reground cams in Minis, Escorts, Geminis all of which have had increased lift - provided you don't want to go *too* beserk with the duration - as far as I'm aware it's a pretty standard practice.
Increasing the lift is simply a matter of reducing the size of the basic 'circle' of the cam lobe, effectively making the peak higher. . .
Of course, maybe there is a Suzuki-specific reason why this cant be done - something like the base circle being too small to begin with, or there not being enough adjustment in the standard rockers to take up the base circle reduction or something. . . .

Pete in Perth.

The best visual description can be found here:
http://auto.howstuffworks.com/camshaft2.htm