NA F8B Tuning!

[Brayden]

You can get a cam regrind done on the standard unit.

[boosted_alto]

@ Brayden

Whats a Regrind ??? lol ! How is it done ? Is it easy or Difficult ?? How much performance increases using it after Increasing Compression !

[Brayden]

A regrind is where the base circle of the lobe is reduced to allow the cam to be re-profiled for more duration or lift.

The benefit of more lift/duration is that you can get more fuel and air into the motor, which obviously improves power, and works best if you have ported the head as well. It is all a measure of how far you want to take the performance.

Here's a good FAQ on the subject:
http://www.cranecams.com/?show=faq&id=2

[boosted_alto]

@ Brayden

Thanks alot ! How much mm's would I have to grind for 9.5 : 1 Compression ??!

Cheerz !

[Brayden]

That would be for a cam profiler to work out.

[boosted_alto]

@ Brayden

What if a Cam Profiler is not available and I have to do it as a DIY like every other thing. What then ?!

[Brayden]

It isn't exactly a DIY kind of job sorry!

[boosted_alto]

Alright buddy no problem !

[toyoda81]

Hello from finland!

This is old topic but... i read this and i just decide write of my project...

I building my alto´s f8B n/a engine.

Specs: compression 10:1, camshaft 288degrees and 9mm lift, Two kawasaki gpz550 TK 27mm carburettors, Lighter flywheel, Ported head(160cfm intake, 152cfm exhaust), 3-1 exhaust manifold(32mm diameter, 390mm pipes each),

With those mods, I would be better than i wish...

It has tested without grinded cam... with stock cam.. And it was really rocket.. dyno: 42kw@7800rpm

I wonder what it is with new cam.. My friend who owns that dyno... says about 67kw-71kw@9000rpm....

(sorry about my poor english language...... )

[Billie]

Hey mate. Sorry but any mods to the cam on these engines won't give that much of an improvement, maybe 50kw max.

Sounds like a beast.

[toyoda81]

Hey mate. Sorry but any mods to the cam on these engines won't give that much of an improvement, maybe 50kw max.

Sounds like a beast.

Yes i know it...

But head intake and exhaust have to grind and polish.. In stock it have poor flow. Intake 24mm diameter.. I grind it 29mm and i chance bigger valves.

With this mod it will be seriously better.

But it so hard to get power out of this engine..

[Psi_Wagon]

Hey mate. Sorry but any mods to the cam on these engines won't give that much of an improvement

youd be surprised! you can really feel my engine pickup dramatically after 50kph, and it quite easily revs to 100kph in 1st gear (f8b auto)

compared to a flat power curve and only going to 60kph stock. its a massive improvement

[Billie]

It may be abit beefier, but where you make the power up top, you'll lose some down low. I'v been told a few things about re ground cams, some people say it makes a hell of a improvement, some say they didnt notice a thing. I guess it depends on what stage too. For me i just want top end power (lead foot), so i'd get as lumpy as i can.

[toyoda81]

It may be abit beefier, but where you make the power up top, you'll lose some down low. I'v been told a few things about re ground cams, some people say it makes a hell of a improvement, some say they didnt notice a thing. I guess it depends on what stage too. For me i just want top end power (lead foot), so i'd get as lumpy as i can.

Well.. i drive my alto only on rallysprint tracks. On gravel or paved roads.. For now, with stock cam it is good on street but when i go to rally roads.. There is always pedal to metal... on off throttle And if it have that stock cam.. it is too slow.. too long gears..

I wonder where i can get F5B engine gearbox.. Here in europe or finland.. Here is only f8b engines and those "long" gearboxes...

But i solve this broblem with tighter non-synchro gears and tight final gear..
Expensive but fun

[Billie]

A f6a or f5b 5 speed would be good, coz same final drive, but an extra gear. Japan would be the best place to get one.