Stage 7 with Velocity Stacks

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I didn't dyno test the before and after but the midrange was definitely better. Top end felt the same. I used 2 inch OD copper pipe. You could also use 2 inch exhaust pipe if you wanted. Probably cheaper.

I have the same set up as Mark, but used exhaust pipe - definitely helped in the midrange as long as the carbs are set up right in the first place.

Mike
 
would it be better to use the copper under the carb like a spacer and then buy the vs54 170 stacks
 
Why haven't one of us come up with a reasonably priced Stage 7 set up for the masses ? Seems as though there would be a strong market and there has to be a way to do it cheaper than the regular sources are charging! Maybe I am too cheap for my own good.
 
New here so please forgive me. I am very interested in velocity stacks, and have been looking for where to get them at. But after reading this it seems like you all are just building them. Do any of you have a close up picture of the finished product? I would like to see them. Thanks
 
Did you see the picture at the beginning of this thread?
 
No stack at all pulls hard 7 K up and the mid range is soft. 4 inch stack pulls good low from 3-8 but will starve out up top. Short stack 2 inches better in top end. 3 inch stack allows me to pull down to 2000 rpm and up to 9500.
With the K&N filters and stacks I had to put the float bowl vent lines back on and get them back up under the cover due to lean out at 9000 rpm.

.

Im considering this mod for both performance and looks. Do the K&N's still fit under the 'tank' cover with the 4" stacks Mark?
 
Sure do. I slid the filters up the stack until they bumped up against the lid.
 
I see. Have you seen chrome or CF stacks which flair at the top and have a good looking filter for when I run my bike naked?
 
Why haven't one of us come up with a reasonably priced Stage 7 set up for the masses ? Seems as though there would be a strong market and there has to be a way to do it cheaper than the regular sources are charging! Maybe I am too cheap for my own good.

I am running something real similiar to a stage 7.
DJ Air Restrictors
DJ Stage 1 Adjustable Needles
V-Boost eliminated
Chrome Individual Air Filters
Crank Case Breather with a puke tank.

I guess I have about 175.00 in my complete setup.
 
No stack at all pulls hard 7 K up and the mid range is soft. 4 inch stack pulls good low from 3-8 but will starve out up top. Short stack 2 inches better in top end. 3 inch stack allows me to pull down to 2000 rpm and up to 9500.
With the K&N filters and stacks I had to put the float bowl vent lines back on and get them back up under the cover due to lean out at 9000 rpm.

Here's the procedure. 1 piece of copper pipe 12" long, have it cut at your hardware store on the threading machine and tell him not to put hardly any pressure on the pipe cutter because it will put to much of a bend on the end of the pipe you want it as straight as possible he shouldn't charge you for that. After you have cut the copper pipe into 4-pieces 3-"inches long your going to smooth the ends and clean with thinner or something similar to remover any metal shavings. Next your going to Lowes or any other big store that would have the 2" heavy duty flexible couplers. You will need to buy only (4) cut rubber in half saving the part that fits the copper pipe . You can use the straps off the coupling to fasten rubber coupler to carb and copper pipe. The filters slip over the velocity stacks. Use the existing filter clamps to tighten the fitment.

Have a couple questions... Do you know how much HP gain you get? Is there enough clearance under the lid for a 1 1/2" or 2" rise? Also, does it eng bog down at lower rpms?

BTW: Thanks for posting your carb tear down. I had a air/fuel mix screw hung in the hole on #4. I took the set off, drilled, and got it out with a square ez out. After I put the carbs back on and did a test run, I found #4 wasn't putting out. Finally discovered that carb's main jet screw came loose and the jet was walking back and forth a 1/4". I believe the screw was loose for sometime and the jet popped out when I removed the rack and turned it on it's side. This was a rebuilt carb I had put on 3 yrs ago. Had to take the rack of carbs back off, but didn't have to disassemble with using a 'L' screwdriver. Anyway, by looking at your pics, I had a good idea what I was looking for, and my guess was correct.
 
I don't know exact numbers, just that stage 7 low end was much better with the stacks. I could give it WOT from 1500 rpms in 5th gear and it would pull fine. Midrange seemed better too.

I used 4 inch stacks so a 1.5-2 inch rise is fine.
 
Hello Mark I have a question: if you were to put the stacks under the carbs would you get the same effect as a high rise on a car ? and put the filters directly on the carbs ?

I`m just inquiring about different configureations.:ummm:
 
I don't know, I haven't heard of anybody trying that.
 
Same principle as your reference. The tract would be "longer" but not sure if it would really give you any gain. I think you have to add the whole thing together anyway (total tract lenght above and below the carbs) to see what the "runner" length would be.

Sean
 
I haven`t heard of it being done either but, maybe it would be an interesting test project.:hmmm:
If I only had a garage I would try it but one can`t do shit in a carport and it`s suppossed to rain again today and that makes things even worse
For working and projects.:bang head:

I don`t have any test equiptment but it would be interesting to hear from someone who tried it and has more experience.
 
Hello Mark I have a question: if you were to put the stacks under the carbs would you get the same effect as a high rise on a car ? and put the filters directly on the carbs ?

I`m just inquiring about different configureations.:ummm:

How do you put the stacks under the VMAX carbs? Under the VMAX carbs are the aluminum intake runners..

No once you get this config tuned properly there are no flats spots.. Once you start screwing around with slide drilling, changine PAJ's thats when you get the low end bogs and farts.. Just mess with the main jets, needles height, and spring pressure on VMAX carbs.
 
I was thinking either in between the v-boost or rid the v-boost and go hi rise.
like I had stated, i`m not that experienced at all with the v-max v-4 engine so, im just thinking "What if" I have mechanical ability and I have always been a tinkerer but You guys know way more than me about this bike so I openly accept and respect all of your advice, ideas and criticism :worthy:.
<<Dave>>
 

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