I have the GYTR (carbon fiber) and it performs very well especially for low end torque. I didn't study all the various tips though. I relied on Raptor720's dyno testing and his recommendation based on the type of terrain and riding that I do.

Updated message to include:

I run an open airbox with White Brothers PowerFilter (very free flowing foam filter) and a Dynojet kit with 148/150 mains running at sea level to 3,000 feet max.

I only ran the GYTR once around the yard but can tell you that there is no comparison between just the GYTR and the GYTR with airbox mods and jetting. I wouldn't waste my money on a tip if I didn't plan to rejet and modify the airbox.

/NotuRaptor

 

Rob 660 well lets see I have had the GYT-R carbon fiber and GYT-R aluminum pipes on my first Raptor that was stolen. I got the carbon first, no doubt it is slick looking and it woke up my Raptor, not real loud. But after about 20 hours where the pipe and carbon fiber meet it broke?? My dealer gladly refunded my money and I got a GYT-R aluminum pipe off ebay for like $120. It had the same gains in power just about as loud looked good as well, I didnt have it on my Raptor that long b4 it was stolen so I cant give you a long term report on it. Though it was destroying the spark arresstor??? ONe good thing about the GYT-R pipes was I didnt have to rejet but I also had the stock filter and box on. On my current Raptor I had the complete R4 and it is NASTY!!!! I had just the pipe on for a while then decided to get the headpipe. The headpipe design leaves alot to be desired. I wasnt to happy with it. I also put on a K&N Pro-Flow and a Dynojet stage 2 jet kit as per White Bros. and it was perfect first time out. It pulls way harder than the GYT-R pipe's but damn is it LOUD LOUD LOUD. But I dont have the spark arresstor in, plus you can buy a quite core for it. The power gains are unbelievable. At the same time I installed a Big Gun race series pipe on my friends Raptor. It has the jets and Pro-Flow as well. It is not as loud even with the race insert in but is also not as strong as my quad. But I think his overall finish looks better than mine, and the headpipe was easier to install. I hope this helps you out. Personally I dont like the look's of the E series on the Raptor it just look's funky. Good pipe though, I just think the R4 matches the Raptor.

 

How much of your gain with the R4 was due to the K&N and Dynojet vs. just the pipe. A true test would have been to either rejet with the GYTR or not jet the R4. Trust me, I've got the GYTR with Dynojet and K&N, which were added after the pipe, and they made a big difference. They say you don't "have" to rejet with the GYTR but that's just to make it sell better. Any pipe will do better once the intake and jetting are modified. I'll bet the GYTR and R4 are the same once the jetting and intakes are the same. JMO.

 

Well first off I woudlnt of even run the R4 without rejetting it. Just the pipe only flows way better than the GYT-R pipe did. I'm not saying it's not a good pipe(not trying to start ****) but there is no way that gains would be the same. When you stand behind my Raptor you can tell she is breathing heavily. The GYT-R pipe did not do that. Just my thoughts. It basically comes down to what you like and what you want out of your quad.

 

MBRP is suppose to comming out with a slip on pipe in about a week.
The price is 279 and its rated at a 3hp gain without jetting or airbox
mods. 12 hp with mods. The best part about it is that its only rated at 95dc. I loved the sound on my banshee with fmf fattys but loud pipes
definatley cause problems. Thats why I plan on keeping my raptor quiet
as I can.

 

E-series

 

slappie is right. raptor01blue, it is okay to say you like the R4 but you are trying to justify your decision based on an apples to oranges comparison. The big difference in air flow is that you modded the airbox with the R4 thus allowing it to push more air out the exhaust. More air in = more air out.

There is barely any difference in power between all the tips on a stock motor using the stock headpipe or even an aftermarket one. An aftermarket headpipe may give you a little more top end but then you will lose lower end torque. Again, this is all talking about a stock engine except for airbox mods. I wouldn't waste the money on the aftermarket headpipe unless you plan on changing some of the internals in the engine or you are after "looks".

/NotuRaptor

 

I really like my Pro-Circuit T-4. Sounds healthy and provides plenty of Mid-Range and some Low.