Hey I am probably the biggest skeptic of all... I will be getting complete dyno charts for stock and with the pipe/air box mods. When I get the motor work done I will get the dyno's from that also.... I should be getting my quad back in 3 weeks (they are wrapping the pipe up this week, then it is a 2 week turn around on the chroming) When I get it back I will post all the dyno's on my site

 

Why would it be hard to believe that a 660cc thumper, once unplugged, could make 50hp? Heck the stock YZ250F makes over 30 at the rear wheel, the 426 makes over 40, so why couldn't the 660 make an easy 50?

All the quads made today are choked to death in the intake and exhaust just to meet sound levels. A little uncorking and rejetting can make quite a bit of difference.

There's so much more potential in this motor once cams, carbs and compression are dialed in. I wouldn't be surprised to see 70 hp, or even more on alcohol.

People don't give thumpers enough credit.

 

I had LRD pipes on my Banshee and they worked extremely well. I've since sold the Banshee and went to the Raptor, so naturally I would give LRD the chance to sell me their pipe for the Raptor as well.

I just called and spoke to Eli about the Raptor pipe. He said that they were still working on it because they weren't happy with the power gains yet. He said that they were considering just using a slip on silencer and only using full pipes for big bores.

From what I gathered, they were looking to gain 7 - 10 HP over peak from the slip on, which would put it right at 45-48 HP. About 2 more weeks of developement and over a month before they are selling any.
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My Take:
It seems that there is a growing consenus that the stock header pipe(s) is sufficient for a stock bore and stroke Raptor. This is basically the same thing that Powroll and also TC Racing (one of the guys on this board has his prototype silencer) have stated.

Also, it looks like 48-50 hp is going to be the limit without going into the engine.

My question it this. With the use of digital ignitions, why can't someone develope a high-compression piston/ cam kit in conjunction with an ignition that retarts the timing and bleeds off cylinder pressure at low speed so as to not require the use of race gas. From my understanding, this is what is done with the YZ426 using a throttle position sensor, so I don't see why an aftermarket company can't do it for the Raptor.
Also, there is an over-abundance of low end torque. I'm sure there are lots of folks willing to trade off a few ft. lbs. of torque for a cam that will bring the top end HP up quite a bit. This seems like a simple job for an aftermarket cam.

 

Bash
... not to argue with what you said, but I know when I have called to inquire about the status of my quad, 95% of the time the guys that answer the phone (Jason and Eli) are not up to date with what is going on....(I mean that as no insult to them... they always got about 100 different things going on at the same time...)

I heard a little talk about doing just a slipon around a month ago.... but only in passing conversation. This last week they made the biggest improvements so far.... and they were messing with the legth/dia of the cone on the megaphone for optimum results.... The bulk of the time they have spent r&ding it has been on the header portion on the pipe... They may be going to just sell a slip on, I am not sure.... I know when I call they just connect me with Dave or Arlin. As of last week they were very, very happy with the results they had got.... I know I personally seen the dyno's last friday....

anyways time will tell

 

Brad,

What you wrote could be very true. Eli may not know which end is up when it comes to the Raptor.

Anyway, like I said, they make a great Banshee pipe and they spent extra time helping me through the jetting process, so I'd be leaning their way on any other pipe as well.

 

Have you seen the dyno chart of a stg 3 dynojet kit w/full race pipe at: http://www.quadstore.com/sys-tmpl/dy...runs&UID=10017?

 

So what you want is a variable compression engine? The only company I know of that has ever done that is SAAB.

What does low speed cylinder pressure have to do with Race Gas?

Does the 426 have variable cam timing?(I seriously doubt it but it would be really neat if it did.)

I just don't believe you completely understand what it is that your asking for.

 

NakedRaygun,

You are correct, you don't understand what I'm describing.

Race gas is required when the cylinder pressure causes regular gas to prematurely detonate. Detonation or pinging occurs most often when the engine is under a greater load and more often than not, when at low to mid RPM. At high speed, when the engine isn't under quite the load as at low speed and when the cylinders are not filled with air as effeciently as at low speeds, you can get away with a little more compression (and timing advance for that matter).

A long duration cam can allow you to run a little more compression because at lower speeds, the overlap can actually bleed off some of the air in the cylinder which reduces compression and the tendancy to "ping" or detonate. At higher speed, there isn't as much time for the cylinder pressure to be lost durning the overlap and the engine becomes more efficient at producing power.

Along with this, the digital ignition could be timed to get the best results at any speed.

This is what I referred to in my other post, I just didn't take the time to explain it all, thinking that everyone would know what I meant.

 

Bash, I have TC silencer and this was TC words "No company will make a better stock head pipe for the raptor, no nead for a different head pipe unless you do internall motor mods." Tom told me that the power is there you just gotta know how to make it work, he said the power curve on the raptor is around 5000-6000rpm so all you need to do is bring the power curve down to around 2000-3000rpm for xc racing so you can pull taller gears in the woods. He said it all depends on what type of riding/racing you do as to what you should do to the raptor. I am a firm believer that you dont need a aftermarket head pipe I have rode raptors with aftermarket full exhaust and to be totally honest I still think mine has more low end tourqe and is equall up top plus I am running stock airbox set up, because the stock air box set up is sealed pretty good and for racing xc in mud/water I think with this set up you have less risk of getting dirt/water inside. I have in water crossing full tilt and have yet to have my quad bogg or get water inside the airbox. So I think it all depends on what type of riding one is doing as to what should be done to the quad I am in no way an expert on this just going from expeirance and what I have been told and seen for myself.
Bash I ordered the carbon fiber clutch (barnett) for my raptor I will let you know if it too helps with fade. I hope!

 

I wander if they opened the Air box up. Probaly not.