Hi all
After some advice, i am fitting a Franspeed Supertourer to an iron St4 200. What sort of port timings should i be looking at for the exhaust to work properly?
Currently the barrel has just had a tidy up and timings are Ex - 167, Trans - 122, Inl - 147. I'm happy to open these up to suit the exhaust but need a rough idea of where i need to be timings wise.
Carb will be a 28mm PHBH with adjustable power jet.
Cheers Andy
Supertourer port timings
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You've got a nice torquey set of timings there. You could get a little more without entirely spoiling the bottom end by going to EX 170 TRF124 INLET 150 but it wouldn't be a huge boost, and it will ride like a dream as it is on that pipe.
with just 22 degrees blow down that exhaust wont work as you say "properly"
Yes exactly lol
[quote][
Re: Supertourer port timings
Post by eden » Tue Jun 23, 2015 6:02 pm
with just 22 degrees blow down that exhaust wont work as you say "properly"/quote]
As I'm pretty new to matching exhausts and cylinders, can you explain why this doesn't work? & What pipe would work with that kind of blowdown timing and why.
The reason I'm asking is that the RT190 has similar timing (170/126 blowdown22) & doesn't work well with a supertourer (according to a post on another site) but it seemed the perfect pipe for a touring tune?
Re: Supertourer port timings
Post by eden » Tue Jun 23, 2015 6:02 pm
with just 22 degrees blow down that exhaust wont work as you say "properly"/quote]
As I'm pretty new to matching exhausts and cylinders, can you explain why this doesn't work? & What pipe would work with that kind of blowdown timing and why.
The reason I'm asking is that the RT190 has similar timing (170/126 blowdown22) & doesn't work well with a supertourer (according to a post on another site) but it seemed the perfect pipe for a touring tune?