Re: CMI 496 headers
 

The 496 Kit

Complete with Headers, distribution tubes, all required hoses and brackets for relocating of accessories.

If anyone requires more information or details, please contact us at (847) 623-2737 or [email protected]

Hope everyone has a safe and enjoyable 4th of July Weekend!!

Re: CMI 496 headers
 

Dave, I was wondering about that humidity too. However, I plugged all the numbers into my dyno correction tables and it doesn't make much difference, maybe 1/2% correction. The low Baro accounts for 2% more correction. Must of been one hell of a rain storm that came through on that test...LOL. It's nice to see a dyno sheet with all the data, for us analytical types. The raw numbers are impressive though, and the second run would warrant about 2.5% additional correction than the stock run. Are these the runs that Tyler Crocket did or a seperate test?

Re: CMI 496 headers
 

A dyno run can say anything, back to the original question of this thread, any more real world results out there, that's all that matters. Would love to hear.

Re: CMI 496 headers
 

We recently installed a set of the CMI onto a Baja 35 Outlaw, twin 496 HO. The installation was relatively straightforward, and the couple of problems that we did encounter were handled quickly by Fred at Trick and CMI.

The boat runs great - noticeably quicker in the middle, great sound and looks SO cool. Did we get 50hp? Maybe, we don't have a dyno... It looks like a net result of 3-5mph on top, although we are still playing with props a little to see if we can't squeak out a little more.

I have some good photos if anyone wants them (I can't seem to post them...)

-David
THUNDER MARINE
727-501-3183

Re: CMI 496 headers
 

why the 92 octane in the second chart- did timing get tweaked?

Re: CMI 496 headers
 

Barometric pressure in the 28's indicates a hurricane. Relative humidity of 103 is also very unusual. These numbers indicate cheating or maybe just carelessness.

Re: CMI 496 headers
 

this is the problem! "Maybe".....

"Looks like 3-5mph" ?? It either is or it isn't!

why does evrybody screw with more than one variable at once without gathering and writing down info after EVERY change?

can't anybody just bolt 'em on and say I gained x RPM and/or y MPH with no other changes?

and then take the next step and add prop if nec. and report the net results at that point.

for crying out loud has nobody heard of scientific method?

anybody heard of a stopwatch and repeated before and after acceleration runs from/to various speeds?

When is somebody gonna document that these things work in boats, not on a dyno?

everything I read about this upgrade is clouded with poor documentation/reporting or bad methodology.

this is not chump change for a twin engine boat! before I spend that kind of coin I want to see a well documented verifiable real world trend in dozens and dozens of boats of a dollar-worthy increase in performance. I could care less if they "sound cool" I'm not dropping 7-8K to "look awesome" "sound cool", I'm doing to increase performance including, but not limited to going faster top end. Jeez, mufflers are the norm for most of us now so who cares about "bark".

Re: CMI 496 headers
 

Well said Rippem, we have all been waiting for actual results!

Re: CMI 496 headers
 

Very well said, I agree completely..... BUT, I must admit, I am right at or very near the rev limiter with my 288 and a stock 26 B1 on my HO, so if I installed a set of headers, I would most likely need a prop change to compensate ... The correct way would be to buy a stock 28 B1 before installing headers and test before and after... most real world experience I have heard is right at 3 mph... some 2 some 4..

Also, taking out the turbolators is supposedly worth up to 15 hp,, so in essence the CMI's are producing approx 40 hp over stock, at 12-15 hp / mph, I would expect to only gain a max of 3mph,,, so for 3,500 plus another 500.00 for a new 28 B1 your looking at 4K for 3mph... Not on my budget, not yet anyway,, maybe when they come down to about 1,800 for a set... :cool:

Not to mention I have been waiting for Hardin to perform their independant dyno test on their 496 set-up for months now...

Re: CMI 496 headers
 

right-on...

try 7-8K for 3-4 in a twin app. 2K+ per MPH is at the top of the $ food chain as far as I'm concerned.

alot of people are. The torque and compact design of a Tri-Y system may be as much of an advantage for more reasonable $