If you do go bb I'd like to see it run this winter. I was thinking of going that route on the olady's 700.
turbo or big bore
- Thread starter CATKILLER
- Start date
If you do go bb I'd like to see it run this winter. I was thinking of going that route on the olady's 700.
Turbo
It Sounds Lke Your Still On Thre Fence But When Your Ready To Make That Move You Need To Meet With Silber And Talk More About The Set Up He Knows His Turbos And He Will Take Care Of You.
It Sounds Lke Your Still On Thre Fence But When Your Ready To Make That Move You Need To Meet With Silber And Talk More About The Set Up He Knows His Turbos And He Will Take Care Of You.
Here is my 2 cents.
Lowering the compression WILL make it less sensitve to detonation. AND... it will also make the engine deliver less power and torque at low RPM's... lower speeds threading thru the trees.... It will have less low end grunt...
In the cost and benefit analysis of a low compression head....one of the benefits are that you can run more boost for a given octane fuel, one of the costs is less power until the turbo can make effective boost (low rpm torque will be compromised).
This is a balancing act… there is no “free lunch” here.
Until you make effective boost, the engine will, for all intents and purposes, be naturally aspirated and drawing thru a restrictive intake (thru the compressor wheel, the charge tube, elbows and airbox)... low comp engines don't make as good of a "boondocker" as normal compression engine. Weather that is turbo or naturally aspirated.
If someone sells you a kit for pump gas to run at your elevation and tells you that you will be able to run that "pump" gas at your elevation... get a written guarantee on that... If it works well... great, you will be the best spokesman they could have for low altitude sales... if it doesn't, then you are not on the hook for thousands of dollars.
You are in a unique position that you have good, oxygen rich air for your sled and don’t lose the kind of power that people at elevation do. This is a "luxury" that most mountain riders just don't have...oxygen rich air.
No matter how you look at it, there are no setups that can go from 1000 ft to high altitude (8000+) without adjusting things and spending time to get it dialed in.
IMO... at your elevation, the Big Bore is your best choice for pump-gas solid boondocking performance. It is not the power "numbers" but how the power is made and comes to play in your riding.
I'd call Carls, talk to Chris Kasel in the performance department about the big bore... He will give you the straight answers and not try to sell you something that will not fit your needs. I'm not sure that THEY have a setup for your altitude... but definately better to get the info directly from them.
Silber, those numbers seem a bit off to me (octane, altitude etc). Are you sure that you got them right?
You seem to be saying that you are running low quality, 91 or less octane gas from a farm storage tank (which might indicate water content)…. At 7.5 lbs boost at your elevation with a low compression head and it is performing well with no deto?
10-12 lbs on 91 ("pump gas") octane, even with a cut head, at elevation, either sounds like a recipe for disaster or you would have to cut out so much compression out that it will be a dog at lower RPM. The same for the 7-8 psi at lower elevations. I am familiar with turbo setups out there today as well as lower comp heads. The 700, with its shorter stroke, even more so than the 800.
Last point… all the power in the world won’t do you any good unless your suspension, front & rear, are quality setups.
Whatever you get...do some more research... ponder it for a few more days and then make up your mind. And good luck in whatever you choose... keep us posted.
Lowering the compression WILL make it less sensitve to detonation. AND... it will also make the engine deliver less power and torque at low RPM's... lower speeds threading thru the trees.... It will have less low end grunt...
In the cost and benefit analysis of a low compression head....one of the benefits are that you can run more boost for a given octane fuel, one of the costs is less power until the turbo can make effective boost (low rpm torque will be compromised).
This is a balancing act… there is no “free lunch” here.
Until you make effective boost, the engine will, for all intents and purposes, be naturally aspirated and drawing thru a restrictive intake (thru the compressor wheel, the charge tube, elbows and airbox)... low comp engines don't make as good of a "boondocker" as normal compression engine. Weather that is turbo or naturally aspirated.
If someone sells you a kit for pump gas to run at your elevation and tells you that you will be able to run that "pump" gas at your elevation... get a written guarantee on that... If it works well... great, you will be the best spokesman they could have for low altitude sales... if it doesn't, then you are not on the hook for thousands of dollars.
Rob’s personal sled last season, I believe, was a stock bore 800CFi on twin pipes...not sure on the porting... He was super happy with it from what he told me. His sled has also benefited from great suspension setup AND a systematic approach to making the sled better overall. He has also ridden ALL of Carls packages from mild to wild... he would be a great person to ask in a PM what his opinions were. He has also ridden quite a few of the turbo packages out there...
You are in a unique position that you have good, oxygen rich air for your sled and don’t lose the kind of power that people at elevation do. This is a "luxury" that most mountain riders just don't have...oxygen rich air.
No matter how you look at it, there are no setups that can go from 1000 ft to high altitude (8000+) without adjusting things and spending time to get it dialed in.
IMO... at your elevation, the Big Bore is your best choice for pump-gas solid boondocking performance. It is not the power "numbers" but how the power is made and comes to play in your riding.
I'd call Carls, talk to Chris Kasel in the performance department about the big bore... He will give you the straight answers and not try to sell you something that will not fit your needs. I'm not sure that THEY have a setup for your altitude... but definately better to get the info directly from them.
Silber, those numbers seem a bit off to me (octane, altitude etc). Are you sure that you got them right?
You seem to be saying that you are running low quality, 91 or less octane gas from a farm storage tank (which might indicate water content)…. At 7.5 lbs boost at your elevation with a low compression head and it is performing well with no deto?
10-12 lbs on 91 ("pump gas") octane, even with a cut head, at elevation, either sounds like a recipe for disaster or you would have to cut out so much compression out that it will be a dog at lower RPM. The same for the 7-8 psi at lower elevations. I am familiar with turbo setups out there today as well as lower comp heads. The 700, with its shorter stroke, even more so than the 800.
Last point… all the power in the world won’t do you any good unless your suspension, front & rear, are quality setups.
Whatever you get...do some more research... ponder it for a few more days and then make up your mind. And good luck in whatever you choose... keep us posted.
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C
CATKILLER
Active member
mountainhorse youve made lost of good points here. this decision is getting hard ive rode big bores but only rode one boosted sled and it was a superchargerd nytro. and it was way above the 2 stroke level. like you said i dont want to loose any low end grunt when running thru the trees.
i guess i need to think about it for a few days and talk to the guys at carls cycle to see if there kit will work here at my elevation
thanks for all the imput from everyone
dan
i guess i need to think about it for a few days and talk to the guys at carls cycle to see if there kit will work here at my elevation
thanks for all the imput from everyone
dan
S
Silber
Well-known member
Hey cat killer, i am no genius on either topic but to me it seems like if your riding petersville one day and turnagain the next there wont be much for tuning since there really is no were to ride above 3000' feet in are area. So tuning will never be a problem once you get it dialed in, but since you wont be able to run higher psi on just pump gas id say go with the big bore IMO. Im in the same boat as you really cause i dont know which to get since most my riding is in the local area but it would be nice having the turbo for arctic man since i get about 400 miles there each year. Really though just cut 20 peices of paper out n put BB on 10 n turbo on the other 10, then mix it in a hat n pick one. Youll be happy either way.
How much Hp does a 860 produce anyhow?
J
Jkinzer
Well-known member
nobody knows, and carl's doesnt dyno, but they will take you out and show you the difference and believe it a SIGNIFICANT difference from a stock 800cfi to the carl's cycle 860 kit
If I were a betting man... Approx 180 hp from the 860... that is an "educated guess".. [corrected numbers]
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I have to urge you toward the turbo.. However there are a few things you have to know about.. When yu get the turbo you have to "learn" how to ride it. It is a totally different expierence than riding a NA sled. I ride mine through some of the tightest trees up and down through ravines and nasty sidehills all day and I have not had any problem with the low end or "the dreaded LAG" A good clutch setup can pretty much clutch the lag out. Now the main reason that I say go with the Turbo is because power is so addictive.. I know when I got mine I thought I would run it at low boost and "be safe" halfway through the first day I had it cranked up and a huge smile on my face. I have not turned the boost down.. The BB is stuck at what ever HP is has. Rob will have a lot of reasons on the other side of this though so ask him. He is a big proponent on the BB sleds.. And actually he likes the 660 685 sleds. I sure hope this helps make ur decision.. Go turbo and never look back!!
'cuss....In all fairness... and not meant as a "shot" at you.... When was the last time you rode all day at sea level to 3000 and dealt with the challenges of deto. and the level of boost you run?
I too am a BIG fan of the turbos out there... If my posts above dont show that it is because of crappy typing on my part.
My recommendations are taking into consideration his altitude and his desired riding style. With the dense, O2 rich air that he has... the line is blurred a bit between power convinence (fuel/tuning) and simplicity.
I too am a BIG fan of the turbos out there... If my posts above dont show that it is because of crappy typing on my part.
My recommendations are taking into consideration his altitude and his desired riding style. With the dense, O2 rich air that he has... the line is blurred a bit between power convinence (fuel/tuning) and simplicity.
J
Jkinzer
Well-known member
i know that i told you turbo all the way earlier as well, but MH knows his chit as good or better than anyone i know, and he takes all variables into consideration when advising one on such a decision. i love my turbo and will never own another non boosted sled ever again, but i ride at 6-10k ft and very rarely any lower than 6k. elevation does play a big role in what you are able to do with a turbo, so if MH says to go big bore ( and supports his reasoing with factual info like he has)i personally would take his word for it
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Jkinzer,
Thank you very much for the "props"
BUT...
I dont claim to know more than anyone on here... and there are a LOT of people that know MUCH more than me... I just want to put some good questions out there and hopefully help people look at all sides of a decision.
The Big bores that are out there may not be tested at your altitude... maybe there are some "flat land" companies that specialize in this stuff that you should be asking as well.
Thank you very much for the "props"
BUT...
I dont claim to know more than anyone on here... and there are a LOT of people that know MUCH more than me... I just want to put some good questions out there and hopefully help people look at all sides of a decision.
The Big bores that are out there may not be tested at your altitude... maybe there are some "flat land" companies that specialize in this stuff that you should be asking as well.
My buddie just installed his SLP 777 kit and we rode it on my pond it ran well and they claim 91 octance & 160hp @ 3000ft. My house is at 1947ft and we had no problems on 92. The kit is $2995.
Eric no offense taken what so ever.. To answer your questions,, NEVER I have never ridden 0-3000'
As far as BB goes I think I am going to convert to the dark side and agree that you will get all you need from an 840-860 kit.. Also listen to MH and find someone who specializes in low altitude motors. You will be way happier in the end.
Dusty
As far as BB goes I think I am going to convert to the dark side and agree that you will get all you need from an 840-860 kit.. Also listen to MH and find someone who specializes in low altitude motors. You will be way happier in the end.
Dusty
B
BullHead
Member
i'll be mainly running at 200ft to 1500ft where i am with the turbo, and we have ****ty gas up here, my turbo in my jeep always det, but lucky theres still av gas here, and should be good with water/meth injection, but i'm a mountain rider stuck here, so when i go on vacations back home, i ride 2000-8000ft, so the turbo works really good for me 
, cant wait to bag on it
, cant wait to bag on it
RMK-King
Super-Moderator
Thats what only 3-4lbs of boost on a turbo sled? Could probley almost run 87 octane for that low. The price is about the same to.
I too ride ALOT of tight trees, boondocking/technical riding. Having been around several different turbo setups and BB's and owned both, my preference is a good running single pipe BB. Consistant, predictable, strong off the bottom for getting over obstacles and jumping open creeks with no approach.....you know, the FUN type of riding that gets bark and pine needles all over the sled 
Turbo's have their place and the builders are making them better every year but they have their downfalls....less bottom end, higher engagement typically, fuel quality concerns, reed failures, boost leaks, sticking rings (lead deposits with race fuel)....all little things that can be dealt with, but things that are nice to know BEFORE you buy. Again....JMHO-
Turbo's have their place and the builders are making them better every year but they have their downfalls....less bottom end, higher engagement typically, fuel quality concerns, reed failures, boost leaks, sticking rings (lead deposits with race fuel)....all little things that can be dealt with, but things that are nice to know BEFORE you buy. Again....JMHO-Besides carls n slp who makes a polaris big bore? And besides carls does anyone make one for a D8?
