Head Shaving Question

[madkaw]

Head work discussions by Braap in FAQ is what I reference. Porting work seems the least needed for a street motor. Getting a head that operates at full advance on todays gas on a performance tuned motor seems to be a better priority-IMHO.   

Not sure what you mean by spin out.  The point of the P79 is that there is NO chamber work other than shaving! Maybe some unshrouding-done. On a flat top piston it wouldn't necessarily need shaving . 

[2eighTZ4me]

Well - the motor is nothing more than a big air pump. The more air in and out - the more power (with required fuel of course) So - whether you achieve that via porting, camshaft, or a combination of both - you're still adding power. Given identical fuels - you'll make more power with the airflow than you will with a timing advance or higher compression. Although, the higher compression will certainly lend to better results - but again - you have to tune around the fuel you'll be using. I can make far more power with my turbo setup than a NA setup for the sheer volume of air that's being passed through the motor. I don't need to shave, port, bump, grind, quench or otherwise to get the air through there. But, since we're talking NA - I think the gains by porting/cam will far outweigh the benefits achieved by shaving/shimming/timing.

 

Edit...let me back up and say that if you're running SU's - yes - the shaving and compression is going to give you a boost. If, however, you're running a larger runner EFI intake, or AT LEAST 40mm carbs - the flow is going to benefit you more.

Edited January 15, 2015 by 2eighTZ4me

[NewZed]

Well - the motor is nothing more than a big air pump.

If this was true, the shape of the combustion chamber wouldn't matter at all.  

Edited January 15, 2015 by NewZed