Big Bore Engine Upgrade

[JMR]

I was given two choices when i had my engine built.... torque monster (stock valve sizes) or big horse power (larger valves)    Where and how i normally ride, big end power is nowhere near as important as monster torque so i stayed with the stock valve sizes.

3rd gear out of a corner with the back tire spinning and the front wheel up in the air is great fun!  

i  also had the benefit of having been able to line up against an engine exactly like mine, same FCR's, cams, lightened crank.. the difference being his engine has bigger valves Vs. my stock size valves..... out of the hole i win every time.... roll on's.... i win.... only on the very top end does he pull me.....but i dont ever get to those speeds unless doing a track day.

top end testing of a 1349 engine on the street is a sure fire invitation to either death or the pokey.

According to the fella who built my engine the FJ has a very inefficient combustion chamber and by increasing the pump (piston size) ,in conjunction with the stock size valves, actually improves cylinder filling via the increased intake velocity..... like i said it only bottlenecks on the very top end where maximum volume/flow is required to keep accelerating.



where that stock valve size choke point happens on the speedometer in real life is way above my comfort zone on the street so i dont really feel like i'm missing anything.... even though the dyno says i am missing some HP on the top end as compared to Andy Y's engine.


 on the street.... 115 lb/ft of TORQUE ROCKS! (especially with my fully loaded saddlebags)


In life....

KOokaloo RULES!  

And the intake ports aren't that great either.