heat sinking? Too rich? deep snow bog

[Twostroke]

I do not have a airbox to put on, or I would happily try one and I do not want to buy a airbox just to cut it up and glue it back together to get it to fit back into the chassis with a 800 in it. The stock air box draws air from the top of the hood(tach hole) and would get clogged with snow faster then pods with lots of vents.

There has to be another option, that's why I'm thinking snorkel...

Again, I have little to no snow under the hood!

It's not that I want to keep the pods but tracking down a airbox could take weeks or months and I'm sure polaris wants a arm and leg for one. It's deep no and I want to ride. Plus, I rode with a ski doo today that bogs just as bad in deep snow with a airbox as my sled with pods, lets think outside the box!

 

[mike_s]

Snow hitting the pipe and flashing into steam does little to leave behind evidence. Perhaps you can build something to pull air in from just above the stirrup area, if every other surface seems to get blocked with snow. Generally the best place however is just behind the windsheild or in the handlebar post area...

Good luck!

 

[sled_guy]

Twostroke, I hear all your arguments for not building an air box but you won't fix it reliably without one. I've tried more than you can imagine. Even with socks and LOTS of vents, when the hood gets covered or ground speed drops the under hood area becomes hot, especially behind the motor where the carbs sit. On minute its pulling good, cool air, the next nice warm air.

Even building a snorkel that comes down and ends right at the socks won't work because as the temps under the hood build you end up with positive pressure under the hood that actually keeps air from flowing in through the snorkel.

To get it to run consistant and strong all the time you are going to have to seal off all the air that can get to the carbs from under the hood and only pull fresh, cool air from outside the hood.

sled_guy

 

[Twostroke]

That's exactly my idea. I guess I spoke wrong when I said snorkel I meant; having tubing coming off the carbs and routing it up and outside the hood with a filter on it, the filters or filter would be outside the hood like turbo guys. "Cold air intake" as some call it. I know this would fix the problem but don't like the way it will look, I went and bought $70 worth of stuff to build on this morning and started on it but starting to rule it out because affraid it won't be tough enough, my sled rolls a lot..

another route I'm considering is that I have some big pod filters, and considering running some tubing from the carbs and having the filters right up against some vents on the upper console/lower back of the hood, close enough to me that I can swipe the vents clean every now and then..

Thoughts on either of these ideas? got all day to build and tomorrow to test before real riding this weekend.

Thanks for all the input so far dudes!

 

[sled_guy]

Now you are bringing up some interesting topics.

I've seen the tubes from the carbs up and out of the hood before... sort of worked.

Problem is that intake length matters as does intake volume. And carb venting matters as well. There is actually a science to building air boxes that ensure they right pressure diffs and such. With the tubes, you need to make sure and vent your carbs at the correct location so that you don't end up with an over/under rich situation.

Yeah, its a hard thing to figure out when building a custom sled. That's why sticking as close to stock with some of the things like airbox and pipe saves you some headaches.

I think your best bet is drawing air from the hood vents somewhere that you can periodically wipe clean with your hand.

sled_guy

 

[Trixter99]

Sounds to me like your pipe is melting the the snow and making a bunch of steam under your hood. We used to have this problem on our PSI motors that ran pods. The steam fills your under hood area and the engine sucks all that wet air in and bogs the engine down.

 

[Twostroke]

You know, I could see that being the case.

 

[Twostroke]

here's what I built, hopefully I don't have issues like sled_guy is talking, runs good on the stand in the garage. Too hungover to test ride today

 

[t stone]

Have you pmd Winter. I believe he has built a few IQR mountain sleds over the years. He might have some Ideas for you. I had a dragon a few years ago. That POS would starve for air on the deep days. I had to keep removing the snow off the intake vents on top of the hood. And you are totally right about the killer snow up at Bachelor right now. We went up today. EPIC. Good luck on your fix. You cant miss out on the deep fresh.

Stone

 

[Twostroke]

Tested the intake and it didn't work. ran fine off the bottom but couldn't get enough air up top to fully let it rev out, kind of bummed..

Forgot my pods and ended up riding without any filters today, ran the best it ever has in DEEP snow, only bogged twice and both times it was able to power out of it.

For tomorow, More vents, different filters, leaning the needle out a clip and starting a search for a airbox..

 

[mike_s]

Did you run it with the intake you made without the screen or with open carbs?

 

[Twostroke]

I tired the intake a pictured, then without the prefilter, tired without the filter, then pulled half the of it apart and ran it like that, all still not getting enough air.

Just can't get enough clean air when riding deep snow. On a knee deep day this sled is awesome, once you start sinking up to your waist deep it sucks.

Thinking of maybe rigging up a fan or two?

 

[mtn_rider08]

My sled is doing that too. My exhaust is getting plugged up and the rpms drop down and kill the engine. It's deep up there isn't it?

 

[poorider]

Your problem is exactly as sledguy is telling you. Pods do not work on mountain iqr's in powder. End of story. They barely work on edge chassis in deep pow.
This was my solution and it worked in all conditions...

The first two pics are of the larger modified intake I ended up running for two seasons with NO PROBLEMS.
The last pic was my original design but the intake was a bit small and didn't have enough surface area to flow well in over hood pow.
This was all on an '06 iqr with a non ves 800 under the hood. If you want more pics let me know. This sled never ever had an issue with intake temps or too much powder.

 

[winter]

IQR

Wow !!!! you guys are very creative with your intakes.
Yes, the plumbing will not work, it is not always the powder that is the problem but the power consumption required in the deep snow, you need lots more air then you are getting.
We would generally retro fit the IQR 600 airbox to fit the 800 carbs, this was by far the best and easiest to maintain, always worked in the powder.
We would run the 900 race motors with non/foam pods and allow cold air to enter through back/consel. Were did you get this sled/800???, is the motor stock?

The riding was great today!!!!
I hope you can get this this on the snow, just get a large volume of air in, try not to use any pipeing if you can help it, unless it is very large dia, like 4".

 

[assault 700]

the pic of your intake where your y the pipe go to 4"or 5"and pipe it out of the hood how you did with the filter then drill holes in the side of the pipe where the pre filter covers the more the better tape the pre filter to pipe try that . and the uni filter is just staving the motor for air you have on there under the pre filter