Ozrider (Les) Big Bore exhuast, 1st in world!

[barbagris]

 

[scot in exile]

Please hurry up I have work that needs done

 

[Claviger]

Gents,
Please put your hearts back in your chest and don't wear them on your sleeve for this. Huge thansk to Dyno Steve at DynoSteve Performance for the inexpensive dyno time, chatting, and for allowing me to wrench with the bike on his dyno and get these tests for us all! Please remember today was MORE ABOUT THE V-STACKS than the pipes!!!!

As a result of today's efforts, I'll be publishing my 3D design for anyone to order and use. I make not a single cent, its all worship to the gods of speed!

First off: The bike needs to be tuned, as delivered it was super fat from New Jersey, it still is, but swings lean at high RPM. There is more power once tuned, I have an appointment on the 10th to get it tuned, so these numbers will come up some, of that I have no doubt at all.

The most interesting part, I can FEEL a big difference on the bike vs the CES headers, which means, there IS a good bit more power than with CES, but the numbers don't match up to what I was given upon delivery so, I caution against directly comparing the actual numbers, instead compare the curves of today's dynos and the Carpenter dyno.

Three tests were run seen below:
Run 05: PX-500 Filter, Velocity Stacks
Run 06: Velocity Stacks
Run 07: Open Throttle Bodies

This run is as I delivered it for dynoing, PX-500 filter in place, running Shell V-power 92 octane I got on the way to the dyno.

Filter removed and stacks left in place, NO other changes were made, runs were about 2 minutes apart, as expected it made a bit more power (+6.2hp/+6.8lb-ft):

Now this is THE most interesting plot. This is allegedly the "best" way to make power, well frankly, it's not!! Going from open stacks to open TBs (-4.2hp/-10.7lb-ft). Again, about 2 minutes apart, NO other changes were made.

This is all of them layered together, and I asked him to include last year's dyno for ****'s n giggles. MOST notable here, you can see the telltale carpenter 265 torque dip at 4800-5000 ish, something that's almost completely eliminated with the stacks in place. More to follow on that after this:

Finally, this is today's run with open stacks overlayed against my Carpenter sent dyno plot. If you look at the shape instead of the peak numbers, you'll see that LES exhaust coupled to the stacks is making a broader flatter curve that carries up top just as well as the Brute pipes did (to 8200, my hard limiter).

The comparison of the shapes, the fact my bike's now lean up top, weather, and dyno calibration differences between two dynos in my mind, settles this as a complete success, with more power on tap when the bikes re-tuned. The number may be 10.9hp behind, but I would bet a significant amount of money, if I strapped my bike as it sits, on Bob's dyno with no changes, the numbers would be nearly identical to what he originally sent me.

EDIT: Improved accuracy of final plot overlay.

 

[Claviger]

I should also mention:

Timing has been dialed back 5 degrees at full throttle vs the carpenter dyno, whether that costs me I don't know, I don't really care though, as my bike has absolutely insane compression and I'd prefer not to melt a piston!

 

[barbagris]

God that sounds good.

 

[JohnsoD]

Bad A&& pure thumbs up.

 

[scot in exile]

Tyoe of machine used
Elevation
Humidity
Air temp .

I know Bob recommends running open velocity stacks now I served my apprenticeship with British Leyland(which does not say much) but open velocity stacks is not something I would run on the streets.

 

[Claviger]

Nah, never on the street, not this guy!

The key things were proven:
Ozrider's Pipes make good power
Stacks are a benefit not hindrance to power on our engines with the big cams. I don't think it was ever a question that they could shift around the torque peak, but, validating my design and dimensions was key for me.

Now I can proceed with the very last power generating change I'll be making, and sadly, it can't be dyno validated, but instead requires a track to generate air pressure.

 

[1olbull]

Tyoe of machine used
Elevation
Humidity
Air temp .

I know Bob recommends running open velocity stacks now I served my apprenticeship with British Leyland(which does not say much) but open velocity stacks is not something I would run on the streets.

V-Stacks for on the strip for MAXIMUM GREASE?
Hey, I just had sudden inspiration!
Me reckons a T-Shirt design coming on . . .

 

[BigKel]

I thought it would make more torque than that with the 2" header. Looks like the V stacks work a treat