The PT provides ALOT more top end than the PSI pipe I had previously. Duncan Racing's ad claims a 2000 rpm increase over the stock power curve and I believe it! The power never feels like it falls off on top. 2stroke, have you ever tried the Paul Turner?

 

I have seen the PT, FMF gold, Trinity, CT and an LRD pipe dynoed on the same quad with only changing jetting as was required by each pipe. The Ct, PT, and FMF pipe were all within 2-3hp of each other, with no clear winner in overall power output. The trinity and LRD pipes put out as much low end power and torque as the afore mentioned pipes, but continued to pull another 1100 RPMs higher than the others. While the Trinity pipe was more versitle than the FMF, CT and PT, it still fell short of the LRD which was up by 6hp and 8lb of TQ at the top of the RPM spread, and doing this at almost 1000RPMs higher than the other pipes could even pull. And this was with the LRD adjusted to its shortest setting which focuses the power more towards top end, I have not seen the LRD adjusted to its longest setting ( power in the low-mid range), but if it is exceeding the other 4 pipes in low end power when it is set to run top end, I would imagine that it would be a beast in the woods and trails.

Fat and skinny of 500 pipes: If u can find one, get an LRD, baring that, I would have a custom pipe made to its specs. Check these guys out, I understand they build a mean 500 pipe.

http://www.stealth.fsnet.co.uk/

 

I couldn't disagree more..... We have 4 Zilla's in various states of tune around here to play with and have the FMF Gold, old style FMF, Paul Turner, LRD adjustable, Bill's, and a Cobra Pro series pipes to play with. I just took the FMF Gold off of mine and put the Paul Turner on for good. The top end power of the Turner is MUCH better!
The port work on these cylinders a lot of time determines what the engine likes for a pipe. Mine likes the Turner, a more stock cylinder would perform better with the FMF.

 

I have heard that a port job will make it less reliable is that correct? Where did you get yours ported? I was going to send this one to Paul Turner if I do it.

 

I am not trying to start a war here, but I have personally wittnessed all of these pipes on the dyno on the same 500, and the PT is a good bit shy of the top end power that the LRD makes. Many times the Seat of pants method can be decieving. Also, Look at the drag bikes in the dunes, if they are running an in frame pipe, its most likely an LRD or a custom pipe that is made to LRDs specs. Call any of the reputable, non-puppy shops and they will all conferm that the LRD is the best in frame pipe you can get in terms of top end power. A few years ago I even called Duncan when I was in the market for a Zilla pipe and they even said that the LRD will make more on the top than thier own pipe, they also said that thier pipe is not a top end pipe, but more of a mid range. Im not saying that the PT is not a great pipe, but it is not a overrev pipe by any means.


Also, you are correct as to matching your porting to the pipe. The bike in question was a 89, with a 41.5 carb, Boyseen reeds, wiseco stock replacement piston and mild overall porting.

 

Go back and read my posts again. I did not say the Paul Turner is a better top end pipe than the LRD. Part of the original posters question was FMF vs Paul Turner. The Paul Turner is a better top end pipe, especially on mine.
I don't compare mods by "seat of the pants" or dyno numbers. Real world performance is what we use. As an old drag racer I learned long ago you don't race dynos or manufactures claims. Sow me a time slip or trophy.

As a side note, the LRD we have is new. Put on Zillariders02 heavily modded 87, it may not stay long as the old pipe (cobra Pro series) seems more suited to his cylinder.

 

I really appreciate everybodys response to my oringinal question. Its just that I noticed with the FMF pipe that I have, it has alot of bottom end and seemed to top out real quick. I noticed this when my friend had just bought a new yfz 450. We had dragged raced several times and we were dead even. I weigh about 70lbs more than him also. I had stock gearing zilla, so I decided to put a 14 tooth sprocket on the front instead of the 13 tooth. Thats when I noticed Zilla waking up. We raced in a field and by 3rd gear I could not see him out of the corner of my eye and by the end of fifth I was about 15 bike lengths in front of him. I did not tell him that I did that of course. If I put a OVER REV pipe on it now, do you think that it would be slower getting to the top of the gear since I would be losing low to mid by putting a over rev pipe on it. Or since I would be holding it floored the whole time, the rpms would be much higher that this would make the bike pull that much harder with 14th front 40th rear.

 

Would you be interested in selling that LRD pipe? I am also having a slite problem with my zilla that is together it seems to be getting to much gas when it is wide open it seems to kind of sputter. I have a 190 main jet and a 58 pilot and that is the way Duncan sayed to jet it but it is not quite right any suggestions?

 

Mine was doing this also when I had just rebuilt the motor. Any kind of jet advice a shop will give you will be on the rich side so they wont have to hear " I jetted it the way you told me to and it was lean and blew up". Just keep doing the plug check. Hold full throttle in third gear, pull in clutch, hit kill switch about the same time. Check plug. In you case, you might see a wet spark plug, but it should be a medium to dark brown. Just go down one jet size at a time until its right. Your carb has plenty enough room underneath it to change it without taking it off. I have a PWK39mm and I was told 190 on the main and 60 on the pilot. I ended up with 175 on the main and 50 on the pilot. After this it ran real well, easy to start and no bogging on full throttle. My main problem was the pilot jet, it was way too rich. I was fouling spark plugs every ride, real hard to start. By the size jets you said you have, it sounds like you have a PWK39mm keihn carb, if so, this might be your quick fix, where I had to spend weeks trouble shooting. I would try these jet sizes and do plug check to see that it is right before you ride. I hope this helps you out.

 

Are u still running the stock carb?? If so I would highly suggest upgrading to a 39 or a 41.5 as the stock carbs on the Zilla are a b!tch to jet, and I have also heard that the PT pipe can cause a lean condtion if not jetted exactly right.

About the LRD, sorry, but I cant part with it, but I think there is one for sale in the classified section on here, they guy is asking like $500, seems high, but if I didnt have one, I would spend the money in a second on it after seeing how it compares to other in-frames.

And concerning if a top end pipe will slow you down? the answer is NO!, I have always thought the Zilla to have more than ample low and mid range power, and why all the hype on a pipe that can improve on this is beyond me, what the Zilla needs is about a thousand more RPMs to play with. Kinda like people downing Banshees because they dont have any low end. What does low end matter in a drag race when u are dropping the hammer at 5K+, in this situation the engine never sees low or even mid range. Not saying that drag racing and top end is the be all end all of the quad world, its just the be all end all in my quad world.