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Workshop => Engine and Bottom End => Topic started by: rmw214 on October 12, 2022, 12:12:07 PM

Title: Sphinx TRX363R HP Numbers
Post by: rmw214 on October 12, 2022, 12:12:07 PM
Looking for some guidance on this. I recently built a Sphinx 350 cylinder with 4 mil stroker(363) with MX port, V-Force 3 reeds, Keihin 38mm A/S carb, OEM intake boot, open aluminum airbox, LED big bore pipe, CR Ignition. I love the motor, am very happy with it and am not trying to bash the builder or anything of the sort. I trust his work and experience but was told it would be in the area of 60-65 hp on his dyno. When I had it put on a dyno locally it made 53 hp. I understand each dyno can vary with different results but was not expecting that much of a gap. On the track it does feel a bit under powered when compared to the 450s. Just looking for some guidance on what I might be doing wrong or where I could gain some extra hp such as going with a bigger carb, aftermarket intake, etc. Thanks
Title: Re: Sphinx TRX363R HP Numbers
Post by: havinnoj on October 12, 2022, 12:52:07 PM
Which LED BB pipe?  350g? 
I would also recommend asking what the port timings are or measuring those, that would be beneficial in helping identify how the motor is setup.
The 38 A/S may restrict it a bit - you could try a 39/40 pwk for a little more top end.
What is your jetting?
Title: Re: Sphinx TRX363R HP Numbers
Post by: rmw214 on October 12, 2022, 01:26:50 PM
It's a 350J pipe. Jetting was last set at 180 main, 52 pilot after some dyno tuning. Was thinking about boring the carb or looking into a Lectron possibly.
Title: Re: Sphinx TRX363R HP Numbers
Post by: The norm on October 12, 2022, 03:08:58 PM
Did your builder port the cylinder with the 350J in mind? If the pipe and porting don't have the same "power band" your motor will not run as it should. Most builders won't throw a hp number out lightly...

Loren
Title: Re: Sphinx TRX363R HP Numbers
Post by: rmw214 on October 12, 2022, 05:47:52 PM
Yes he recommended the pipe
Title: Re: Sphinx TRX363R HP Numbers
Post by: havinnoj on October 12, 2022, 06:36:49 PM
What needle are you using?  And what elevation? 
Title: Re: Sphinx TRX363R HP Numbers
Post by: rmw214 on October 12, 2022, 07:18:33 PM
CEL needle. 1400ft elevation
Title: Re: Sphinx TRX363R HP Numbers
Post by: The norm on October 13, 2022, 05:04:17 PM
I'm not familiar with the 350J pipe. Where is it supposed to make power and what type of riding is it meant for?
Loren