H
08 pipe is fine, us higher elev. riders don't have to worry about can issues, my dealer said he don't care what can i run so i left my hps on it
08/09 800 recall...
- Thread starter greenspeed
- Start date
Since the 2009 D-8 suffered from a "heat issue" and I'm assuming the replacement silencer is free-er flowing than the stock D-8 silencer, it just seems unusual that a silencer from a smaller displacement motor flows more than a larger displacement motor???, that's all.
And why use the 2007 model silencer, rather than the 2008 model D-7 silencer???
Just thought it was unusual.
Since the 2009 D-8 suffered from a "heat issue" and I'm assuming the replacement silencer is free-er flowing than the stock D-8 silencer, it just seems unusual that a silencer from a smaller displacement motor flows more than a larger displacement motor???, that's all.
And why use the 2007 model silencer, rather than the 2008 model D-7 silencer???
Just thought it was unusual.
It does seem unusual. Makes a person really wonder if they stumbled across something by accident or are guessing at this. Nobody else that i'm aware of needs different silencers at different altitudes........Oh, I'm going to ride my dirt bike at 5000ft today I guess I better change my silencer!?!?!?
I'm sorry I am so negative about this
Hats off for them trying to fix the issue and standing behind their product. There is something to be said about doing it right the first time too.
The heat issue IMO is more related to the single ring piston not transferring the heat to the cyl. wall. The can could be changing the flow characteristics, which was affecting the "bog" or the lean issues.
Well i give polaris credit for standing behind there products. But i still have a concern with. They lowered the commpression with the new head that is good if you run a turbo but now for rider's like me that run @ 4500 to 9000 ft we will lose a lot of power IMO i'am not a mechanic just a polaris rider that want's what we payed for. any input on this would be great maybe i'am looking at this wrong
ID - Jim at dyno tech found out that on the cfi 800 a lower compression actually gained hp, proved on his dyno, two different heads, plus Poo factory guys spent some time with him so I think the hp will be ok. also your getting what looks to be a diferent color exhaust spring so it might be a complete kit results thing, just thinking
True on the DTR results, but Jim's comments on the explanation was possible beneficial turbulence from the "top hat" chamber design.
BMP is claiming that the new replacement lower compression head makes LESS h.p. BMP post on here's claiming 148.3 h.p. Dyno graph posted here on SnoWest, BMP thread starter.
Take it for what it's worth.
Didn't hear anything about the exhaust spring.
BTW, are you plugging the exhaust valve purge hoses to eliminate the "emmissions solenoid" that delays the opening of the exhaust valves????
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Agree w/you that the rings are the majority of the heat issue.
Just guessing /assuming that increased flow was the reason behind changing the silencer, what other reasons could there be???
J
It seems that my dealer thinks there are two cans for the 800's.
1. A pure SLP can - 6 lbs lighter
2. A Polaris/SLP manufactured can
I was told they lowered the price on the #1 can - $200 (which is the one I opted for) and the #2 can was the $125 one. I don't know, I guess I will find out in 2 weeks when I get it back. I had the mid range bog at low elevation and got the reflash, that's the only problem or issues I've had with the sled. I just want to make sure its fixed for good.
I would like to see what DynoTech Research comes up with for the new update. I might order one of those PCIII's.
1. A pure SLP can - 6 lbs lighter
2. A Polaris/SLP manufactured can
I was told they lowered the price on the #1 can - $200 (which is the one I opted for) and the #2 can was the $125 one. I don't know, I guess I will find out in 2 weeks when I get it back. I had the mid range bog at low elevation and got the reflash, that's the only problem or issues I've had with the sled. I just want to make sure its fixed for good.
I would like to see what DynoTech Research comes up with for the new update. I might order one of those PCIII's.
True on the DTR results, but Jim's comments on the explanation was possible beneficial turbulence from the "top hat" chamber design.
BMP is claiming that the new replacement lower compression head makes LESS h.p. BMP post on here's claiming 148.3 h.p. Dyno graph posted here on SnoWest, BMP thread starter.
Take it for what it's worth.
Didn't hear anything about the exhaust spring.
BTW, are you plugging the exhaust valve purge hoses to eliminate the "emmissions solenoid" that delays the opening of the exhaust valves????
I'm sure BMP says the HP is down with the new head and I'm also sure they have a shiny new head that will "fix the problem".
Honestly, if BMP is claiming 148HP on their dyno "stock" and selling their gains based on that, then it's likely running closer to 152HP. Just my own skeptical experience w/performance shops talking here.....
I'm sure BMP says the HP is down with the new head and I'm also sure they have a shiny new head that will "fix the problem".
Honestly, if BMP is claiming 148HP on their dyno "stock" and selling their gains based on that, then it's likely running closer to 152HP. Just my own skeptical experience w/performance shops talking here.....
Hey Rocket,
Couldn't agree w/ya more!
I was trying to be politically correct with my last comment "take it for what it's worth" re: BMP dyno results.
x2 on the bold and "the shiny new head"
Check out the BMP dyno graphs, h.p.#'s scribbled by hand @ the top of the graph, LOL
un-friggin-believable
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It may be true that the new stock head with lower compression will work better for some applications / elevations. However, IMO for HIGH elevations a drop in compression from the original stock head (13.5:1), to 11.5:1 on the new head would not produce the same kind of power as we had in 08-09.
After conversation w/ SLP, their testing has also shown that the new compression was not ideal for high elevations. The SLP head gets the compression back up to 13.5:1. It is also advertised to be a 3 hp gain over the original stock head (which I have not tried), and even more when compared to the new lower compression stock head. FWIW, I was told that switching to a higher compression head (for high altitude), produced the largest performance gain in their testing.
I ride 7k-11k, SLP single w/ intake and clutching for the past 2 years with good results. Ordered a '10 that should be here early next week. SLP head is on it's way and will be installed before it hits the snow. Will post results when the snow flys! Won't be too long now
After conversation w/ SLP, their testing has also shown that the new compression was not ideal for high elevations. The SLP head gets the compression back up to 13.5:1. It is also advertised to be a 3 hp gain over the original stock head (which I have not tried), and even more when compared to the new lower compression stock head. FWIW, I was told that switching to a higher compression head (for high altitude), produced the largest performance gain in their testing.
I ride 7k-11k, SLP single w/ intake and clutching for the past 2 years with good results. Ordered a '10 that should be here early next week. SLP head is on it's way and will be installed before it hits the snow. Will post results when the snow flys! Won't be too long now
J
Based on what I've read here - IMO don't buy anything until at least, after Christmas. Then at least we'll have a little clearer picture on whats real and whats not. Who knows... Maybe Craigslist will have a lot of 800's for sale...
How do you know that graph is even for a D-8, let alone a sled motor, no specifics, No A/F mix, No BSFC, water temp, nothing, a couple of squiddly lines with the H.P. #'s hand scribbled @ the top, unbelieveable!
Uh, yeah that looks impressive BMP, I'll take (2) pipes @ $499.00 each and one of those shiny new heads for $419.00
No thanks, I'll wait til some independent company like Dynotech Research tests the parts, like they did in April 2009 on a 2009 D-8. They compared SLP pipes to stock to BMP pipes, Sean Ray $100.00 modified stock heads that out-performed the BMP $400.00 billet head, tests done with and without the PC III fuel controller.:face-icon-small-hap
Last time SLP made the most power, BMP was a dud. BMP pipe made a whopping 2 h.p over the stock pipe.
www.dynotechresearch.com
BEST $25.00 you'll ever spend for informative un-biased info!
It may be true that the new stock head with lower compression will work better for some applications / elevations. However, IMO for HIGH elevations a drop in compression from the original stock head (13.5:1), to 11.5:1 on the new head would not produce the same kind of power as we had in 08-09.
After conversation w/ SLP, their testing has also shown that the new compression was not ideal for high elevations. The SLP head gets the compression back up to 13.5:1. It is also advertised to be a 3 hp gain over the original stock head (which I have not tried), and even more when compared to the new lower compression stock head. FWIW, I was told that switching to a higher compression head (for high altitude), produced the largest performance gain in their testing.
I ride 7k-11k, SLP single w/ intake and clutching for the past 2 years with good results. Ordered a '10 that should be here early next week. SLP head is on it's way and will be installed before it hits the snow. Will post results when the snow flys! Won't be too long now
This too seems like an odd move for Polaris. Wouldn't they want to maintain higher comp for high alt as the RMK was intended and then offer the motor in different trim for the flatland sleds? This whole thing just seems buggered from the beginning.
Now we may or may not need a fuel controller, but likely need a different head? Outsourcing KTM motors at this point sounds like a really good idea for Polaris.
I ride at 4500 TO 9500 feet this is not good for me why can't we just run the stock head that is on it already. If the one that slp is selling is a stock take off head why not any input.
Capt Krav, I'm with you only I thought that Poo said 154 but Jim and BPM said 144hp now it's 148 I had not so impressive results with BPM pipe mods plus their clutch kits suck in real snow, I'm going to investigate this new head thing don't know why Poo would want less hp at alt.
Supposedly, polaris wants the old parts back after the update is complete. (someone who has actually had the update done can verify this for you). IMO, you should get the 2 ring pistons and new fuel mapping, so you will need to do the update to get those. SLP head and 08-09 stock head are two different heads, even though the compression ratio is the same.
here is a good deal for anyone looking for a slp can for their 800.....
http://www.startinglineproducts.com/catalog.cfm?pageID=detail&catalogID=9&catID=69&productID=812
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