BDT 363 Sphynx Build

[Burns310r]

Okay fellas.

I have been riding my new DS 450XMX for the past 2 months in the Iowa D22 MX series due to some issues with my 250R motors. USPS thought it would be a good idea to drop my $2000 insured 2 day mail box containing a 310cc PROX, a ESR 330 PV (BRAND NEW) cylinder and my race BDT 350 ProX. The drop bent the sleeve's of both my BDT 350 and my ESR 330PV (so they where effectively junk). Nothing was wrong with either cylinder i may add when i sent them. Carlos was taking my 330 on trade for other stuff and my 350 was going under the knife for some more aggressive porting. Long Long story short, USPS paid me the Insured value......WOOOT

So now what to do.. Well after working directly with Carlos at BDT to get my 350 ProX dialed in for so long I naturally went back and asked for his help again. And he made a suggestion to me that I hadn't previously considered..... A stroker Sphynx motor.... Naturally I was giddy as a school girl hearing this as i know the Sphynx motors make more HP/Tq vs other cylinders.

So we ironed out what I wanted and after a short week and half, A box showed up on my door containing my brand new Sphynx.

This motor will complete 4 stroker killer. A lot of people say this, but its actually harder than most will admit in the A class MX world these days. It take a lot of work to beat up on the local A class 4 strokes here in Iowa if you havent seen my vids I have posted. These boys dont play around when building 4 poke motors.

So here are the build specs for the motor.

Sphynx 78mm Nikasil BDT Pro Port job running @220 PSI Comp
+4 stroker Hot Rods Crank(brand new good style)
Vforce 3 reeds
38mm A/S carb
ESR TRX5 pipe

This setup should be good for around 66hp and 45 ft/lb tq.

This will be the start of my build thread of this engine, and i will follow up with my thoughts on performance.

Starting.......
When i first got the cylinder, i must say... This thing is a piece of art. The porting is immaculate, the casting looks amazing... Carlos did a amazing job opening up the ports and blending the sleeve/ports.










I will update this thread as the build progress goes on. Should be able to race it after 2 weeks.. Takes me some time to build my motors and get them broke/dialed/practiced on before i race them. But you guys will deff see some footage of this motor tearing up some 4 strokes.

Stay Tuned.

[8686]

Wow. Looks amazing!

[chronicsmoke]

Looks good Burns!! Subbed. How are you riding on the DS compared to your R?

[Burns310r]

I have been finishing a lot better. But i have been getting better all season. Any my last 350 was giving up some HP to the local 450 guys so it was deff harder.

I cant wait to get both the DS and the R on the same track on the same day and compare lap times. Im hoping im faster on the R.

Regardless next season im giong to race the DS in the Production A class, and race the R in the Open A class.

[JackBrown1988]

Wow dude, that is awesome port work. Purdy-purdy-purdy.

[jhtrx250r]

What did bdt do port wise ?
That cylinder looks like they do un ported right out of the box from cp.
Calvin has got his casting down to a science.

[jhtrx250r]

I think you will like the performance of that cylinder, I have the 300 pv set up, it was a little pipey out of the box , so I had the ports droped with a resleeve , it made 55 rear wheel out of the box but that's the 300 kit.
Deadly has a 350 sphinx with a stock stroke I rode it a few weeks ago it pulls good , I think his was 62-65 right out of the box stock stroke.
You will like it, let me know how it works for mx?

[Burns310r]

BDT did there MX pro port on it. Its hard to see any difference becasue they sanded it down so well and put it through some sort of glass polisher for the nikasil process. Im no expert on it but I was assured that the port job on this thing is nasty fast.

Also he had to port it for the +4 stroke, it uses different port heights.

[wes350x]

Pics removed. Very nice Sphynx cylinder Kyle. get that thing running!

[atv fan 28]

Now thats a real port job!!! ^^^^^