It will be easyier to throw a reed cage and reeds in there but the main perk to a dt swap is the water cooling and the powervalve. Is it worth all the work just to make it water cooled?
Well, I'd say the power advantages of the DT200 cylinder are:
1) Water cooling for consistent cylinder temperature (power) which allows:
2) closer jetting,
3) closer piston clearance and
4) closer (higher) compression tolerances and
5) more timing advance with less chance of overheating and detonation.
6) The Powervalve increases torque from 1000-6000rpm
7) which allows higher rpm and power porting from 6000-8000rpm
Also, there may be some weight savings (cylinder weighs less even with water & rad)
and it is a more compact package, slightly quieter and not thermally shocked if you hit water.
This is balanced by the disadvantages of a more complicated system (possible failures) of rad, hoses, and pump.
So without the powervalve functioning you are losing one big advantage of this head,
but still gaining 6 huge power making advantages nearly doubling the peak power.
How bad is the loss of low end torque?
We didn't notice at first because the main jetting was off.
As jetting was improved, the huge peak power difference becomes much more apparent.
Not gutless, but slightly less than the stock Blaster and a BIG power rush on top end.
What can be done about low end torque without getting the powervalve electronics functioning?
1) decrease piston to head clearance.
2) increase compression
3) lower cylinder (exhaust port timing) (all can be accomplished at the same time)
4) advance timing
5) increase displacement, stroker or bore kit.
6) intake divider (PowerNow or similar)
7) longer pipe, tuned more to mid range
All of these will increase low end power. Haven't tried any yet.
May be a while, too much snow for testing at the moment.
But I like the idea of getting the powervalve working, either with a cable to the throttle,
backpressure operated, or off the oil pump drive as Roostinshee showed in another post.
If we had all the electronics, it might be worth hooking it up, complication/battery/wiring be darned,
but we don't. So we have to look for another way. In the meantime, this thing goes like heck!
Why not just put a YZ250 motor in it?
I went that route (sort of) with a motocross engine in my Blaster.
Much more complicated. New mounts, cut swingarm, more rad needed, custom pipe fabrication,
frame interference or modification, weld on brackets, more vibration (that's just the feeling of POWER, boy!),
custom airbox, not for the faint of heart. Most of these MX swaps take months and many of them just never get finished.
The DT200 cylinder swap was quick and tidy and delivers double the HP of the Blaster (3/4 a MX250)
with the same excellent Blaster gear ratios.
MX gearing suck unless you are riding in open country. I have to put up with a too tall 1st and a short 5th gear.
MX has to slip clutch constantly over the rocks and yet limited top speed even if the power seems unlimited.
Yup, I like the DT200 cylinder swap. Impressive.
