520cc NMotion Top End Kit

[370kingR]

Figured i would stick this in here for you guys thinking of a 520 NMotion kit.

This motor had +2 exhaust, +3 intake Stainless steel valves ported by John @ NMotion with Kibblewhite heavey duty springs and an HRC cam timed straight up. Also, using very good MR9 oxy fuel. 13:1 compression, stock carb, P.C. exhaust, and Vortex ignition.

These two particular runs compare HP with the P.C.'s stealth, or "queit core" and regular race versions.....

[370kingR]

Torque....

[370kingR]

These torque maps show different Vortex ignition curves.

[370kingR]

more timing curves

[370kingR]

Here is the same setup minus the Vortex and instead of the HRC cam, it has the web 493/721 grind cam.

Comparing some pipes too.

[370kingR]

Now look at what Dan Lamey of Dasa is claiming my 550 has

[370kingR]

So far we have not had any luck with the clutch hoilding up in the 550 but Matt and i will have some real compaison dyno graphs hopefully soon. 68/50 sounds a bit steep to expect to be quite honest but id take 65/45 if it came my way

[wppracing]

The PC looks good.
What Vortex setting did you find made the most power ?

[370kingR]

Originally posted by wppracing
The PC looks good.
What Vortex setting did you find made the most power ?

#2 then # 5 on that setup as far as HP goes. Very lttle difference between all of them to be honest. You really need to go through the whole rpm range to see what one is best, not just go by the biggest peak power curve.

The difference in peak power was less than a third of a HP between all of them. I look for usable midrange increases where i figure to spend most of my time.