I don't get it, how does the new 500cc Predator kill modded Raptors in sand drags? Go to www.offroad.com and check it out yourself. Is the Raptor motor that de-tuned? The new Predator says that it weighs in at around 420lbs. That's about equal to the Raptor, and it doesn't even have reverse! I own a 01' Ford 4x4 diesel with 255 hp. I was told that the motor is only at around 57% of its peak. That means that there is still 43% more hp lurking in that bad boy. So, what did Yamaha do or not do, to these engines? And why on earth shouldn't a 660cc quad not kill a 500cc quad when they're both 4 strokes? We shouldn' have to dump $2000.00 into our $6500.00 machines, just to keep up with the smaller ones! Let me know what you think, thanks

 

well i guessing how the engine is made also helps i mean a cannondale cannibal can beat a 660 and thats less than a 500cc im not real sure but im guessing the performance depends on how they were built

 

I figure that the prepoduction quad is faster than the consumer is going to get. Would not look good if the predator lost all its drag races.

 

Valid point 14mins.

 

The bike 660 made like 50 hp. It's the de-tuneding.

 

It's all about breathing, Higher cam lifts, bigger valves, better porting & higher rpms = more HP.
It also means that it'll be a high matinentce engine & more likely to eat itself!

That's how we beat V8 powered dragsters with a 2.8 liter VW, of course lighter weight & 30 lbs of turbo boost @ 11,000 rpms helps too.
This little VW motor started life as a 40 HP beetle, Now it has aprox 600 HP. It is also very high matinence! Before every run the jetting & valves must be checked, after 30~100 yard passes it gets main bearings, ETC, ETC. even with very close monitoring & matinence it still does This on a regular basis.
Here is a pic of the VW powered dragster I'm crew chief on in action (we hold the track record at the Ft Worth Texas track)

So yes a 500 can beat a 660 but you'll pay for it.

 

Hey moose that Fort Worth track is about 5 minutes from my house, you'll have to let me know when ya'll are coming back down this way. I plan on coming up your way to Little Sahara in the next month so let me know when you are planning your next trip there.

 

Bartman "detuning" is a common practice that most all companies use, have used, and will continue to use. Any motor that's putting out it's maximum HP for it's size won't for long, because the maximum hp is ususally achieved by high revs and high compression, both cause stress and on the edge-rapid part failures. It allows for vastly longer service life of motorswhile maintaining a majority of their performance ( think since you brought up your pickup motor 10,000 service hours in stock form, or 3 hours at maximum output.)

A standard high performance motor has these basic characteristics. Overbore, high compression, dynamic timing, full legnth con rod, good breathing and superior materials(allows for high heat and revving.)

If both motors have what it takes, it's just a matter of which is bigger and set up better. The 660raptor motor has most of "what it takes" just not all of it...Like it's a compact, a short rod motor, and low compression, no intake header to speak of, and conservatively timed.

 

RaptorRidrTX, I don't know if we'll be back in TX this year with the car but I'm thinking about coming down for the big money quad race (in Nov?) it depends on how close I am in the points at Atoka.

Our next Sahara trip is goning to be combined with a race at Atoka (a bunch of Connection members are susposed to be there) on Aug 9th & 10th & then to sahara for a couple of days.

 

The moose is right on the money. Which ever engine gets the most air into it makes the most power (compression is then the last factor). If you can get 200cfm of air into a 500, it will outrun a 660 with 180cfm (these numbers are just examples. cfm=cubic feet/minute). If the smaller engine spins faster than the big one, even more air can be pumped in.

What you stated about the Powerstroke is true. It is the most detuned diesel offered. Mid '99, ford changed the airbox because it was so restrictive that under hard pulling, the engine would suck the air box in. With the help of a larger turbo and new intake and exhaust, and computer reprogramming, I have seen dyno tests with over 400hp and 750lb/ft out of that engine.