03 F7 - Snowmobile World : Your #1 Snowmobile Forum

justinm7 · 08-14-2005, 03:30 PM

i just bought a 2003 f7 EFI sno-pro. it has a single speedwerx pipe and v-force reeds. how much HP am i pushing and will it be alot faster than a stock firecaT

Rock Port · 08-15-2005, 10:48 PM

From my experience with the speedwerx pipe it won't give you alot of extra HP unless you get it set up with a boondocker, it is way to fat on the top end. An inline fuel restrictor might work also but be carefull. However for the reeds they are 100%. Much better throttle response than the stock cages and reeds. I think if you had the Boondocker set up you would gain an additional 6-8 HP with those setups, as it is now you will be a little quicker than stock but not much.

puree · 08-17-2005, 12:18 AM

Reeds are 100%??? I have heard that the gains with them are very minimal. I have played with other cats with reeds and there really isnt any difference as far as I have noticed. I am not saying it isnt possible, only that I have noticed no difference.

As for the pipe,,, I had a d&d pipe,,, it isnt the speedwerx,,, but still an aftermarket pipe. I ended up taking it off and put the stock one back on as I actually lost speed with the d&d,,, we compared the stock to the d&d on a radar gun and the stock was consistently 1 to 2 mph faster at 660 foot.

Rock Port · 08-17-2005, 08:18 AM

I installed 3 sets of the V-Force 3 reeds in Firecats. All 3 had the same results and the customers were all happy with the gains. You could pull an easy sled length to a sled length and a half out of the hole. To me this is a big difference over stock, however to each there own. It is only a given if you can increase the air intake by a bigger set of reed cages with less restriction over stock and remove the reed stops to allow max air flow it is gonna work. I would also recommend you put in a set of D&D Bullseyes with those reeds. Bottom line is don't listen to what everybody tells you or nothing will work right and you will remain stock, just do it for yourself and find out........the results were good for me.

puree · 08-17-2005, 12:01 PM

I do have the bullseyes and we did notice a slight difference with them. I have 4 of them in. Not sure why I havent seen the vforce work with those I was running with, but they honestly wasnt. I didnt want to invest that kind of money in them with the results that I was seeing. I have been told them really worked for them, but I have also been told there is not difference,,,, that is why I never put them in mine.
I do know that you have to increase your output as well as your input to get that gain. Your motor is nothing more than an air pump,,, so if you only increase one side and not the other, there really wont be much of a difference. So if the vforce is a significant difference in air flow and you go with a opened up y pipe and a pipe that flows more air, then you should get a difference.
So with that said, you have to wonder if those that I was running with only had the reeds, and not the pipe. I dont remember either of them saying they had changed the stock pipe. Maybe that was the difference.

Rock Port · 08-17-2005, 12:42 PM

I gotta agree with you on the Y pipe, I see D&D has a new one out for about 200.00, by looking @ it, it should increase the flow quite nicely. However on the other hand I run mine with a stock Y pipe and speedwerx pipe. You have to understand there is lots of flow, when I say that, they are using that same pipe on F6's and F7's and there is guys using the same pipe on the F8 with no modifications other than a Boondocker. If it will flow for an F6 to an F8 that tells me it has lots of breathing capabilities.

puree · 08-17-2005, 11:59 PM

guess I cant disagree with that one,,, By looking at the d&d Y pipe, I really think one could be made for much less money,,, all it would take is a steady hand, a torch, and a welder.
I looked over the d&d piece and it should create less resistance, thus allowing more air flow. At least thats my take on it.
Wonder if there is a big difference between the D&D pipe and the speedwerx pipe. I took the insulation and cover off my stock pipe and slapped it right on the d&d and it looked stock. The cover fit perfectly,,, so the d&d couldnt be flowing much more than the stock pipe. Maybe the speedwerx is simply a better built pipe.

f7rocket · 12-31-2005, 08:09 PM

I got a f7 with speedwerx domes and speedwerx pipe for trailing, with a f6 pipe i would turn around 7800,I put on a speedwerx pipe and lost 200 rpm's, just trying to figure out y i lost rpm's with the pipe..or will the f6 pipes give the f7's more hp.I only had about 300' to try this, i wonder would the speedwerx pipe pick up more rpm's as it got out further?

puree · 01-01-2006, 02:16 AM

not sure what kind of difference an f6 pipe would make on an f7. You would need to put it on the dyno to see where your peak hp is at, then adjust your clutching to get the maximum output out of it,,,, if the dyno says your making less than 140, go back to stock.
I had an aftermarket pipe on mine and the stock pipe gave me more,,, so the aftermarket version went on ebay and I put the stock one back and and clutched it to that,,, big difference