Talked to Carpenter Racing

Just when I thought I had cooled off from what had transpired between a local stealer and myself who I had a long relationship with I talk to Carpenter and I'm all worked up again. I called them to discus their 3:1 Megaphone Exhaust System and what if anything would the system do for my application. In the discussion it comes out that Carpenter had a customer who had a stock engine 2010 Roadster that they tuned using their exhaust sytem, velocity stacks(no filters and bearclaw installed), and TuneECU. The bike made 168HP to the wheel and pulled hard all the way through the RPM band to 6,900(moved up of course). They stated that they have a lot of customers who run just the velocity stacks with the bearclaw installed and have no issues with anything getting into the throttle bodies. From the conversation I gathered that they aren't a big fan of K&N(they didn't say it I just got the feeling). They talked about how much the filters chock an engine that really needs to breath. I kind of scares me a little to think about running around with no filter(s). I think the tall K&N's I have without the bearclaw and my TORS(CAT delete) may be why I feel that even though my custom map says 159HP my Rocket really doesn't pull like I thought it would. If I was to pull the string for the exhaust to the tune of $1,500.00 for the polished version I'd have it ceramic coated inside prior to intalling it. Then take my bike back to who I'm working with now, have the PCIII removed to include turning the O2 sensor back on, run just velocity stacks with bearclaw, and tune the bike with TuneECU. If that don't get it I'd give up at that point until I could afford to just turn the bike over to Carpenter Racing for either the 210, or 240HP mod.

There is no way in the wide world of sport that I would run my bike without air filters. I see what is on them when I clean them and I don't want that, plus the big stuff that doesn't stick to the filter, inside the engine.

If I was using the Rocket to power my ski boat....then I'd pull the filters

I am curious why would you ceramic coat the inside of the pipe ? Oh if your getting 159 hp out of the tors and it doens not feel the same it could be that the PCIII has a larger span of rpm segment like every 500 rpms and the PCV Bob is using has 250 rpm increments. Personally I am amazed your getting 159 hp out of Tors I think that is the most I ever heard of with Tors with the exception of the Supercharged bikes. If you want to stick with filters maybe you should look at a large Pipercross and see what it does. Bob has not run one of them on th edyno nor anyone else that I know of especially with the Carpenter pipe.

He seemed to like my 1770s, he'd never seen them before, he got 241 on the first run, I think he said, that was unusual.

Ok Wayne you have scared me back into the nothing without filtration mode. I had a moment of weakness. I also recalled my dyno sheet wrong. I pulled it out and it says 146HP and 152TQ. In my mind I must have switched the numbers and read a nine in there somewhere. I seem to be getting a little dislexic as I get older. Talking to a one of the gang at my local watering hole after work for our Friday ritual about not being all that satisfied who has been a hard core biker for years he believes my problem started when I took too much back pressure away. He believes the off idle torque I'm not feeling is due to a lack of sufficient backpressure. Sure once I get over 3,500RPMS it comes to life in a big hurry, but when I twist the throttle from idle the front end doesn't feel like it wants to come off the ground, nor is the bike trying to pull the handlebars out of my hands like it did when it was bone stock. I'm considering putting my stock pipes back on and see if that might make it feel like I want it. I have a couple different maps to try from some nice folks here that are for TuneECU and the shop I'm working with is willing to do a comparrison between what he can do with a PCIII and what you can do with TuneECU. Maybe we will try with TORS and then with the stock pipes. It's too late now, but I'm still wishing I'd left this **** machine alone after I bought it, but that's not my nature. I may end up defying my nature in the end.

Here is my take on things. I have a 2005 R3 standard. When I got it it was bone stock. It would barely wheelie even if you popped the clutch. First I did the resistor mod to eliminate the torque limit in the lower gears. It would then throttle wheelie in first gear. Later, added the small K & N's and Maddog pipes (similar flow to Tors) and bought Tuneboy. Got a tune from Blasted Bones who at the time had the same set-up. Now if hit it hard at walking speed it tries to flip over backwards (literally almost lost it the first time). I noticed no loss in off idle power but sure noticed a huge kick in the arse at 3500. Feels like another cylinder comes on board. Mine has not been on a dyno (yet) but I suspect what your feeling is not a loss of low end, but a "feeling" of loss when compared to 3500 on up. Scott in Exile is running the same set up (and tune I believe). Dave, did you notice any loss of low end ?

Talking to a one of the gang at my local watering hole after work for our Friday ritual about not being all that satisfied who has been a hard core biker for years he believes my problem started when I took too much back pressure away. He believes the off idle torque I'm not feeling is due to a lack of sufficient backpressure.

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Back pressure on a 4 stroke engine is a myth. However scavenging effects are not a myth. If you size the exhaust pipe right the exhaust pulse from one cylinder will travel through the header pipe and collector, and once it passes through the collector it will pull exhaust gas from the other cylinder. This can be seen if you take a air nozzle and blow it in bursts through one header tube (on the manifold side) while holding a peice of paper on on of the other header tubes (manifold side). If its a decent header/exhaust the air traveling through the collector will pull the paper onto the open header pipe.

After a engine does its compression/firing sequence, the piston travels down (thus twisting the crank). When it comes up the exhaust valve opens and allows the piston to push all of the burned gases out the exhaust. If there is significant back pressure in the exhaust (small headers, restrictive mufflers, etc) the piston will have to "compress" the exhaust out the exhaust port. It wont be by much, however it will cost HP because some of the other firing cylinders torque will be wasted . Smaller header pipes typically will give you better low end power (aka torque) but will kill power at higher RPM. This is because at 1,000 to 3000 rpm the exhaust will scavange very well due to the high velocity in the header tubes. However above 3K (depending on head tube size) the exhaust will become a restriction and will kill power. Carpenters pipe is good for big power numbers, but on a stock bike with a 6K redline I wouldn't think it would be that great on the low end.
If the header pipe is too big the velocity will drop off significantly, thus killing the scavenging effect (mostly at low RPM).

Engine building/header tube diameter is always a give/take approach. 5 more HP at 10K rpm with a 15% loss of torque below 4K rpm by running big header tubes might be worth it to a non street driven bike, but on a street driven bike it would likely be a better match to run the smaller tube headers. Also many dyno operators don't tune bikes on the low end (under 1500 rpm) well and it could be that your bike is lacking fuel at low RPMs. Get a wide bad 02 sensor and see where the A/F is at on low RPM pulls. My guess is there is more power to find by retuning the low end of the bike.

I have to agree with Gregory on the tuning low as most do not because thats is not what people brag about its all about the big numbers. Myself I do not care about the numbers and would keep mine classified anyway My point is what Gregg's point is you need better tuning down low the mor efinite control of things the better a tuner is able to refine. Provided the tunere is willling to. Like I said a PCV unit has more finite rpm control when compared to a PCIII unit all you have to do is down load a PCV map from Power commander and you will see its rpm break down is every 250 rpms where the PCIII is 500. I am not sure about the throttle percentage you will have to look. But for sur ethe tune software aids will have more finite control as well as timing control and if you tuner has a break dyno you will be able to hold things and make finite changes with the tune ecu. Here is where the right tune boy set up is just better (but you have to pay its not free hack ware) It has live tuning which mean you see the changes you make live not wating until you reflash the ecu to see if what you chose works. This type of software also has a Target Telemetry sight which allows the operator even more finite control of changes. I am not trying to promote tune boy over tune ecu as both are them best out there provided you tuner knows what he is doing. Your upper dyno numbers are right in there for the TORSso I suspect soem lower end fine tuning is what you need.
Also since you are from Suffolk VA. and are subject to vehicle inspections you might want to keep in mind the fines that are levied for vehicles that are modified beyond the Virginia guidelines. This does not meen it can't be done as some places do not look it over with a fine tothed comb. but if a copper gets picky you might develop some problems with a wide open megaphone. I never paid attention to what Harleys do down there so by all means take this with a grain of salt. I spent many a year in Norfolk and can say I have paid more for a inspection sticker without a inspection then it would cost to keep paying for the rejection stickers

Does carpenter provide a base tune with their pipe when you buy it?