Porting
- Thread starter Zac
- Start date
Street Ryderz
Well-Known Member
There is some simple porting that anyone can do for decent gains without messing up the timings, this would be to widen the exh port by a couple mm each side and radius the corners along with chamfer the edges. Same with the intake and if feeling ambitious you can correct the transfers exh side wall angles by back cutting them to match the opposite wall's angle.
noah9988
Well-Known Member
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- Jul 3, 2021
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The proper way to do it is measure your current port timing and then adjust the timing by enlarging the ports a certain amount. What you want your port timings to be and how much material you need to take off isn't something I can explain though.
Street Ryderz
Well-Known Member
The proper way is to have a known port map that works and is attainable in the cylinder your using and also ideally suited to the range your engine and setup is capable of.
Enlarging the ports by width does not change any of the timings it just helps to get more volume through, port timings are what control how much, how fast and when the phase's occur and it's best to have an understanding of how and why the timings have to work together before going and messing around with them!
Setup is a big part of how an engine will preform and by this I'm not talking about how you installed the engine by this I mean the parts used to setup the engine and the tuning of it, this also includes having a port map that works with the parts you intend to use for example 170 degree exhaust timing's with high blow down's and all the intake duration in the would won't make your engine rev faster or up higher because you put a bigger carb and a pipe on and were told to raise the exh timing, that's just not true and not how it works.
Pipes have to be tuned carbs also and the engine should be setup to match the flow rates starting from the carb through to the pipe for any real gains to be had, porting is not just hogging out a port or flange area without considering how much it can flow based on the carbs volume and flow rate first and foremost.
I have listed port timings here that I know work well for these engines with more grunt down low where we need it and will suit most peoples needs for street riding, I've given out my own timings that I use for my builds and they are far from some of the crazy high timings I've seen many people try thinking they will go faster.
