Adjustments after adding new mufflers

[pggg]

TC, one of the fellas one this site slotted his cam sprockets and tweaks with cam timing. Can't quite think of his name at the moment. I remember he knew all about dialing in cams. Hawk, smaller diameter header pipes supposedly boost low end torque too.

[turbopete]

For dialling-in cams you need:

A degree wheel - a disc with 360 marks printed around it 1 degree apart. They are cheap to buy, or you could print one out and stick it to a disk of metal or plastic. The degree wheel normally mounts to the L/H side of the crank (although I don't know about the reverse-turning XS engine). Here's a pic:


A dial gague - a simple engineers measuring tool used for measuring runout on a rotating part (plus other things) - another pic:


A positive stop - a plug that screws into the plug hole of No1 and stops the piston reaching TDC in order to set up the degree wheel. I made mine from an old spark plug, but after that I decided to use my dial gauge with an extension to set the TDC.

Here is a nice article on how to degree cams:

http://www.compcams.com/Information/Tutorials/

[turbopete]

Actually that link explains about valve timing - these are better:

http://www.fordmuscle.com/fundamenta...ng/index.shtml

Another good one, with a lobe-centre/duration calculator:

http://www.rbracing-rsr.com/camshaft.html

I did a little test by inputting my hayabusa cam timing:

Camshaft Lobe Center / Duration Calculator
Camshaft Name / Number : hayabusa turbo
Intake Opens BTDC (ATDC is -) : 11 (in degrees)
Intake Closes ABDC : 42 (in degrees)
Exhaust Opens BBDC : 24 (in degrees)
Exhaust Closes ATDC (BTDC is -) : -1 (in degrees)

and it gave me this result:

Camshaft Calculations - Lobe Center / Duration

Your hayabusa turbo has an Overlap of 10.00 degrees and has in Intake Duration of 233.00 degrees. The Exhaust Duration is 211.00 degrees. The Inlet Cam has an Installed Centerline of 105.50 degrees ATDC. The exhaust cam has an Installed Centerline of 106.50 degrees BTDC