Silent But Deadly

[cannondale27]

This motor was ported, tuned and run with STOCK airbox and filter with the STOCK Breadbox 03 exhaust totally intact and tested at 93Db with pump gas.Timbo Intake Cam and Waynes Exhaust Cam and Buckets.Stock new valvesprings.Not quite 50hp but close enough for both me and the new record 432cc with quiet exhaust.Very happy with the power.It really holds it on top.Plenty of time for shifting.Now the DNR can look elsewhere for sound violations.Had to put a fitting in headpipe for the dyno's afr tube since I didnt want to touch the stock exhaust which has screens and baffles in it which dont allow probe in end.Once again Thank You Mikes Cycle for dyno time.Great new dyno guy there also he did my Raptor which murdered my dyno tires .
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[cannondale27]

Wow either factory really missed the boat or Timbo and Mark Matczak really know how to port.

Same quads stock airbox and exhaust except this one was a ATK 450cc.Even the extra cc's couldnt help it enough to beat the stealth!

[peterock]

I wouldn't count chuck's as a good comparison as he was trying his own custom porting. Odds are he did more harm then good.

Plus keep in mind you had aftermarket cams in as well.

[cannondale27]

Pete that was Rogers before he had it.Brand new and Bone stock never touched by anyone.As far as I know it was the only stock Cannondale/ATK ever dynoed at Mikes.Cannondale could have easily made cams the same and porting the same.ATK could also.They didnt Timbo,Mark,Wayne and I did.Its a fact.From what I hear a STOCK Cannondale with 432cc piston is around 38hp on dyno.All other stock Cannondales dynoed at Mikes had at least a aftermarket silencer or a Ti FMF none of which will pass sound.And all were still less than this one.

[peterock]

I would say no gaurantee with Chuck. He was always messing with something.

[UpsMan]

I remember that day. Chuck did take what ended up being my ATK up there and ran it on the dyno. That was the first time and last time he ever ran it I believe. It was completely stock at the time, toaster exhaust, it was a 450. Didn't he also run his ATK MX on the dyno that day too? I'm curious what that put out for power with his "homemade porting" and high compression piston.

[cannondale27]

I will look around for that run.Currently Mike Cousins Sr. owns that one.

[wayneschofield]

Just checked my printout from my first Cannibal.
It was just broken in, serviced plus about five hours running to run the high spots from the tranny and stuff before stripping the thing down for updates, so about as fresh an engine as you could expect. It was totally stock and toaster-equipped.

It made 37.7 wheel horsepower and 45.9 at the flywheel. That was on my Bosch dyno that is pretty accurate all round.

For comparison, on the same day our Ben's freshly built, completely stock, YFZ made 29.8 wheel and 37.4 flywheel horsepower and our Jake's 250 Quadzilla made 13.7 and 18.2 on the same day, and that is rated in the book as 18bhp, so the dyno shows pretty close.

[cannondale27]

I took the highest of all the readings he got.38hp was actually the average.So I would say my dyno is very close to yours Wayne.Good to know.

Maybe these were actually the runs.Were done different day.None are labeled very well.
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[cannondale27]

UPSMAN here are his from the one he ported.I know it didnt have stock exhaust though.FMF?Anyway that covers all the runs he ever made so take your pick.I thought I was being generous with my statement if anything.Took a few years to break 45hp and alot more work and time to break 50hp.Now it seems routine but it really is a impressive feat considering our small group.Think about it 65hp was broke this year.That is getting near double the hp of stock without power adders!

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