Tunnel fab. ? for everybody

maxdlx

maxdlx

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If a guy had an old tunnel say off of a 97 sx, and needed a tunnel ext for a 02 viper, and the sx tunnel is just slightly narrower? Could you cut the old tunnel, and make it your ext. I was thinking 8 inches tucked undere the viper tunnel, and the rest hanging out. then I could use my rear exchanger. As long as I can get the running boards to line up and look nice, do you think it would work. Maxdlx
 
traditionally tunnel extensions go on the outside, but I don't see why it wouldn't work, just make sure you have enough meat left in it to support the weight of the rear exchanger you're either running now or will be in the future.
 
Traditionally???

I don't know what tradition Junior is talking about but I have installed 4 tunnel extensions and they all went inside the stock tunnel. This includes OEM Yamaha extensions, MAXX perf, and Mountain Performance. To answer your question, though, I think you could do that. Only problem is that I also think you'll find the SX and Viper tunnels to be the same size. I have an OEM Mountain Max tunnel extension that I will sell you complete with hose covers, snow flap and the rivets you'll need to install for $100 shipped to your door. I'll need to send you photo's if interested due to a ding in the extension (it cant be seen, it's under the hose cover) and cracks in the plastic on the hose covers (also very difficult to notice when installed). I used a MM extension on my Viper.....just stripped the paint and it looks great. There is nothing like that OEM fit!!

Madmatt
 
Madmatt said:
I don't know what tradition Junior is talking about but I have installed 4 tunnel extensions and they all went inside the stock tunnel. This includes OEM Yamaha extensions, MAXX perf, and Mountain Performance.
Click to expand...

ok, maybe not as traditional as I thought then!
 
One problem you would run into, is a mis-match at the running board angle's.For example the running board width of the "extension" tunnel would be wider then the trailing portion of the tunnel your sled.
Another low cost alternative, if you know someone who has a sheet metal break. You can get some .062" aluminum sheeting and fab one up yourself.
 
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Junior....I wasn't trying to be rude....it just came out that way. Ever read somthing the next day and think to yourself "I should have worded that differently". Anyway, doesn't the extension on your MTN SRX go inside?

On the metal break idea....I've tried it and it doesnt work that great because the tunnel does not have a bend from a break, it's actually a really tight radius bend. A break will give you a crappy fit. On the running board lining up issue....wouldn't you just be cutting that part off??

Madmatt
 
I made one myself from sheet metal. A break does give too much of an angle, but bending it by hand, clamped down with a block of wood gave a perfect fit. I'll have to see if I can dig up a picture.
 
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Here's the best pic I could find. You can somewhat see the fit. Stock rear peice with the flap and rear heat exchanger, stock bumper, trimmed hose covers. Riveted on with some extra supports on the sides under the tunnel to help keep it stiff.
 

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A break does work, you can get the radius you need by doing multiple small bends and adjusting the clamping edge tension. It takes some practice though, that's where having some sheet metal scrap's to practice with, comes in handy!
Because the extension fit's inside the tunnel, the radius on the extension needs to be smaller. The outer radius of the extension would be the same as the inner radius of the tunnel, to compensate for the thickness of the metal.
 
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Nice job Mtn Viper!

Hey MtnViper, nice job on that . I like the kick-up. I don't like the cat skid! LOL!! Seriously though, how does that skid work in there?

Madmatt
 
Thanks Madmatt, the Cat skid works pretty good. The main reason I went with, is for weight saving's (18 pounds). I have one season on it now, and it works better then the proaction. There is a some minor improvements I want make, so......
For my summer project, I pulled the Cat skid out, to do some fine tuning to it. I re-angled the front tip's of the rails up slightly, to reduce track clip vibration. For a better rail to track approch angle. It's not bad , but I notice it. The difference is 1M mountian Cats use 10 tooth driver's, while I'm using 9 tooth's.
Also I had the suspension arms powder coated blue! I also modified the rails to convert the rear idler wheel's from 6 3/8" to 7 1/8" (Yamaha size) for less rolling resistance. Was going to go with 8 incher's, but they will not fit the 136" skid.
I picked up a set of ACT shock's off of a King Cat, they're getting re-valved for my weight and the 136" skid.
 
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