TV 205 BARREL WITH BOOST PORT

[paulski]

I have aquired a heavily modified tv 200 barrel i think.. it has been very nicely sleeved with added boost port and massive transfer feeds,dont know who done the work but it must have taken a lot of time,it is 67.5 bore size and i am planning to try it in my motor with a decent racetour piston, if i use a 60mm crank i have measured the port timings to be exh:182 transfers:132 and inlet:159 plus the boost port duration is 142....... if you compare this to my 16bhp muggy 230 with readings of exh:182 transfers:127 and inlet:163... then wot do you reckon this kit is gonna perform like????? anybody got any thoughts or info on these timings ???? very curious to find out if its likely to be a monster or rideable tune???

[J1MS]

Is it an old Rafferty Newman Barrel ? Or is it a newer conversion.

[paulski]

Is it an old Rafferty Newman Barrel ? Or is it a newer conversion.

havent got a clue as i bought it last year on fleabay, it has a cast lug near inlet manifold stud with number 2 stamped on it from the factory. but someone has done a real pro job on opening all the ports up and sleeving it, cant wait to try it.

[jonny snatchsniffer]

what are te timings with a 58 mm crant

[paulski]

what are te timings with a 58 mm crant

dont know as not tried with 58mm but i would imagine that with 2mm travel differance on the crank stroke its gonna equal aprox 2 to 3 degrees less on each reading???? so 180exh...130inlet....156 transfer.....140 boost port???? i will try and post some pics of barrel asap

[paulski]

http://i1045.photobucket.com/albums/b45 ... CT1592.jpg
http://i1045.photobucket.com/albums/b45 ... CT1591.jpg
http://i1045.photobucket.com/albums/b45 ... CT1590.jpg
http://i1045.photobucket.com/albums/b45 ... CT1589.jpg
http://i1045.photobucket.com/albums/b45 ... CT1587.jpg
http://i1045.photobucket.com/albums/b45 ... CT1586.jpg
http://i1045.photobucket.com/albums/b45 ... CT1585.jpg
http://i1045.photobucket.com/albums/b45 ... CT1584.jpg

[paulski]

what are te timings with a 58 mm crant

dont know as not tried with 58mm but i would imagine that with 2mm travel differance on the crank stroke its gonna equal aprox 2 to 3 degrees less on each reading???? so 180exh...130inlet....156 transfer.....140 boost port???? i will try and post some pics of barrel asap

thats not how it works,

if you put a 58mm stroke in the timings would be

exhaust 177
inlet 164
transfer 124

had a feeling it was more mathematical,how do you calculate that mate, how many degrees per mm??? cheers

[dirtyhandslopez]

Go on Eden, tell us or at least point us in the right direction to find out. There will be some good kharma points in it somewhere for you

[scooty]

you could try here
http://www.lambretta-images.com/forumbb/porttiming.php

[dirtyhandslopez]

Ah, the old port timing calculator trick eh? Damn, that makes life easier.