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-   -   850 big bores? No talk all season about them? (https://www.snowest.com/forum/showthread.php?t=442172)

pauly815 04-15-2018 09:03 AM

850 big bores? No talk all season about them?
 
Been real quite all season, to easy to bolt on a turbo?

cubby 04-15-2018 09:28 AM

I asked the same question a month ago and was told by FEZ who works for SHR the turbo has taking over the BB game. No need to spend money on a BB and lose power at elevation, when you can spend the same amount on a turbo and not lose any.

TreeThrasher 04-15-2018 10:32 AM

Ya we went and ran two turbos with a 927 last weekend. It's not even a comparison between the two. The turbos just pull and pull and pull and the big bore struggled to show any on the hill advantage of a decently clutched stocker.

Chadly 04-15-2018 06:12 PM

I've been saying this ever since I first rode a BB. The money and hassle of still having to run race gas is not worth the measly power increase. Turbos smoke BB's on the mountain.

mtncat 04-15-2018 07:10 PM

Going to send my 927 back east for independent dyno testing as I have found a well clutched stocker will run neck and neck with the 927---go to the TMS website and read Dave's statement on a stock G4 850---- porting a stock 850 does not justify the time and expense of pulling the engine out, also says porting not worth the loss of low end torque, throttle response and increased piston wear. so now we move on to the 927, punch it out to a 85+ mm piston and we have all this power on tap, now is there room to port the 927? or is there minimal power gains in bore and compression alone? is the bottom end grunt from the increased compression? also rode with a ported 850 this weekend and it will drive away from the 927 start to finish. have had very noticeable gains in the TMS872, the TMS927 is a waste of $2300 and once you voice this you become a Red Neck Hillbilly that doesn't know anything!!!! and you see the true colors of your former Engine Builder.

ak 04-15-2018 07:38 PM

Quote:

Originally Posted by mtncat (Post 4147770)
Going to send my 927 back east for independent dyno testing as I have found a well clutched stocker will run neck and neck with the 927---go to the TMS website and read Dave's statement on a stock G4 850---- porting a stock 850 does not justify the time and expense of pulling the engine out, also says porting not worth the loss of low end torque, throttle response and increased piston wear. so now we move on to the 927, punch it out to a 85+ mm piston and we have all this power on tap, now is there room to port the 927? or is there minimal power gains in bore and compression alone? is the bottom end grunt from the increased compression? also rode with a ported 850 this weekend and it will drive away from the 927 start to finish. have had very noticeable gains in the TMS872, the TMS927 is a waste of $2300 and once you voice this you become a Red Neck Hillbilly that doesn't know anything!!!! and you see the true colors of your Engine Builder.

Who’s porting on the 850? I know d&d racing is seeing good gains on the dyno with porting the 850.

fynnigan 04-15-2018 10:06 PM

Quote:

Originally Posted by mtncat (Post 4147770)
Going to send my 927 back east for independent dyno testing as I have found a well clutched stocker will run neck and neck with the 927---go to the TMS website and read Dave's statement on a stock G4 850---- porting a stock 850 does not justify the time and expense of pulling the engine out, also says porting not worth the loss of low end torque, throttle response and increased piston wear. so now we move on to the 927, punch it out to a 85+ mm piston and we have all this power on tap, now is there room to port the 927? or is there minimal power gains in bore and compression alone? is the bottom end grunt from the increased compression? also rode with a ported 850 this weekend and it will drive away from the 927 start to finish. have had very noticeable gains in the TMS872, the TMS927 is a waste of $2300 and once you voice this you become a Red Neck Hillbilly that doesn't know anything!!!! and you see the true colors of your former Engine Builder.

Yup Tms seems to be not so good at standing behind some of their product ,we did 2 872s a couple of years ago , professionally installed ,proper fuel etc. . 1 has run very well the other has been a pos . Lots of base gasket issues ,2 burn downs , keeps,blaming it on the install .bs , skidoo certified tec did all the work .wont give a straight answer on torque spec for the jug ,instructions say 26 lbs. factory is 35 . When we did the first 1 the squish was different from 1 hole to the other ,a lot different .any ways he won’t be getting any more of our money . Oh yeah we heard the hillbilly thing to

JJ_0909 04-16-2018 12:07 PM

What everyone else said. Its a lot of money, time and headaches for a supposed 6-7% horsepower bump.

duncan76 04-16-2018 01:43 PM

Quote:

Originally Posted by cubby (Post 4147693)
I asked the same question a month ago and was told by FEZ who works for SHR the turbo has taking over the BB game. No need to spend money on a BB and lose power at elevation, when you can spend the same amount on a turbo and not lose any.

I didn't know you could get a good running turbo for 2500 bucks

JJ_0909 04-16-2018 01:51 PM

Quote:

Originally Posted by duncan76 (Post 4147875)
I didn't know you could get a good running turbo for 2500 bucks

...you can for ~$500-800 more.

cisco 04-16-2018 06:55 PM

Quote:

Originally Posted by ak (Post 4147775)
Who’s porting on the 850? I know d&d racing is seeing good gains on the dyno with porting the 850.

here in canada ontario , bondi engines did about 15 off those 850 and there very good . 12-15 more hp for trail running pump gas . those 850 love the porting job . oter shop claim near 15 hp stock pipe on pump gas .

jawz pipe have is 850 on the dyno working to make a pipe for it .

Chadly 04-16-2018 09:40 PM

Quote:

Originally Posted by duncan76 (Post 4147875)
I didn't know you could get a good running turbo for 2500 bucks

No but why pay $2,500 for something that requires race gas that makes hardly any more power? I suggest you save your $2,500 for scented oil to put in your tank. For $4,000 you can actually get something that makes a whole lot more power and not have to run any kind of race gas.

duncan76 04-17-2018 07:24 AM

Quote:

Originally Posted by Chadly (Post 4147960)
No but why pay $2,500 for something that requires race gas that makes hardly any more power? I suggest you save your $2,500 for scented oil to put in your tank. For $4,000 you can actually get something that makes a whole lot more power and not have to run any kind of race gas.

Thing about turbo's is I don't like having to tune and tweek on it. Thing I love about my old bb is for 3000 plus miles is pull and go. You hear this and that about bbs but I have yet to come across a stocker or even a we'll set up stocker or or slped cats or poos that can even come close to my bb. My well set up 850 is neck and neck with it out of the hole but on an long up hill pull my bb walks away. To each there own I guess plus I like the scented oil.:eyebrows:

Bacon 04-17-2018 07:33 AM

Up to 6000 feet a big bore might make sense. Above that is turbo territory. I'm happy to see not everyone has drank the TMS cool aid.

BIG JOHN 04-17-2018 07:58 AM

SHR does have a 921 BB and IS noticeably stronger than stock in all areas...

SHR is working with Silber for a ECU tune to make more power/run cleaner than the fuel mods available...

SHR offers the best/easiest clutching with our IN sled adjustable TIP weight kits (MANDATORY for BB/turbo)...

SHR is the only mountain perf shop (in MN.) to offer- proper clutching, turbos, BBs, shock valving, BDs, head cuts, Y pipes, cans and over all set ups ALL tested at low and high elevation by a team of enthusiasts that have been in the business for 20+ years...

SHR BB/clutching $2395 VS turbo/clutching $3995/4295

call for details-BJ

JJ_0909 04-17-2018 09:24 AM

Quote:

Originally Posted by duncan76 (Post 4147985)
Thing about turbo's is I don't like having to tune and tweek on it. Thing I love about my old bb is for 3000 plus miles is pull and go. You hear this and that about bbs but I have yet to come across a stocker or even a we'll set up stocker or or slped cats or poos that can even come close to my bb. My well set up 850 is neck and neck with it out of the hole but on an long up hill pull my bb walks away. To each there own I guess plus I like the scented oil.:eyebrows:

Your logic is a bit off...

If you can have a pull-and-go big bore then you too can have a pull-and-go turbo.

Silber and BD both offer kits that don't even offer "tuning". You set them up. You clutch them right. You go. That's it. If its not working, something is wrong with the sled, you don't have the right octane or your clutching is way off (most likely ;) )

Point is, there is a reason Silber offers an ECU reflash for the Big Bore Bros (BBB). They were having issues with fueling, just like (gasp) a poor running turbo sled!

In any case, Chadly is right, $ for $ the big bore is a tough sell. There are people, for sure, who it makes sense for, but most would be a lot happier with a low boost turbo with clutching to match...

FEZ 04-17-2018 03:09 PM

Like BJ said, we have had a 921 on the snow since June and it runs well and all that ride it say the same. The owner is very pleased with his 921.




But the majority of 850 riders that have the $$ to mod want more power at elevation than a BB can offer. And that is why SHR has focused the last 2 seasons on the 850 Turbo. Last season we ran the MPI, this was the Silber. Next season ???





We test/tune/run at elevation what we sell so you can run the products we offer with confidence.

Bacon 04-17-2018 08:41 PM

Is there a reason your jumping between kits or are you selling all of them?

christopher 04-18-2018 11:28 AM

I see three issues that are at play in the Turbo vs. Big Bore situation.

#1.
Turbos have come a LOOOONG ways in technology and reliability in the last several years. They are FAR more accessable to the normal rider now than at any other time in the past.

#2.
Pretty much any rider can install a turbo kit over the weekend.
Converting your 850 over to a Big Bore means your engine is coming out of the sled.

#3.
The ONLY way to compensate for lost power at higher elevation is FORCED INDUCTION. There is simply no other mechanical solution to lowered ambient pressure as we climb the mountain.
Only a Turbo/Supercharger can overcome that loss.

dave@trygstadmotorsports 04-18-2018 02:48 PM

TMS G-4 927
 
1 Attachment(s)
Great Idea to get an independant dyno test on any aftermarket product as the attached snapshot is what one of our out east TMS 927 customers found when he wanted to verify the product that he purchased. Great way to fine tune for different applications and elevations and make small changes to timing and fueling parameters.

Note to get this kind of performance results you will need to run the TMS 927 designed piggyback fuel controller with our developed fuel mapping and offsets that we include with our kits. Someone trying to re-invent the wheel with thier own ideas on how to add fuel to the sled and not utilizing our developed fuel controller is obviously going to have different results.

There are a good number of very satisfied TMS 927 owners on the snow the last 2 seasons running our complete package- fueling, clutching, etc.

FEZ 04-18-2018 04:12 PM

Quote:

Originally Posted by Bacon (Post 4148108)
Is there a reason your jumping between kits or are you selling all of them?


Supporting as many customers as we can one must test/tune/run what is out there and what customers want. Clutching is a major issue with the Gen4 and SHR has developed its' own adjustable weights to again, help as many customers get the most out of their Doo for whatever application they may have

sledsrock 04-18-2018 05:06 PM

N2O
 
Quote:

Originally Posted by christopher (Post 4148212)
I see three issues that are at play in the Turbo vs. Big Bore situation.

#1.
Turbos have come a LOOOONG ways in technology and reliability in the last several years. They are FAR more accessable to the normal rider now than at any other time in the past.

#2.
Pretty much any rider can install a turbo kit over the weekend.
Converting your 850 over to a Big Bore means your engine is coming out of the sled.

#3.
The ONLY way to compensate for lost power at higher elevation is FORCED INDUCTION. There is simply no other mechanical solution to lowered ambient pressure as we climb the mountain.
Only a Turbo/Supercharger can overcome that loss.


NITROUS.

turbo800 04-18-2018 06:37 PM

Quote:

Originally Posted by sledsrock (Post 4148291)
NITROUS.

***GASP*** WHAT!!

All joking aside, many people probably forget that Boondocker made it roots early on in the N2O market. Do they even offer it anymore?

jim 04-18-2018 06:50 PM

Quote:

Up to 6000 feet a big bore might make sense. Above that is turbo territory.
Nailed it.

Yeah, big bores can and do work at elevation as well...but you can only do so much to make up for the elevation. Forced induction is the only way to get around it.

mtncat 04-18-2018 07:12 PM

2 Seasons? Mine had a power commander the first season, not one single ride without setting check engine lights and limp mode!! have also been around the new and improved dobeck box on the 927, have heard that the silber reflash is
better than your new box but have not been around one yet, A/F gauges are available to the consumer and actually work to get fuel correct!! How about a guy out of Canada, Steve Roy had a 927 the beginning of this season and has since moved on as it would never out perform a well setup stock sled after the 330ft mark, any one can contact Steve VIA facebook and he would be glad to fill you in on all of there test results, it also had the supplied TMS fuel box and map for it to perform at its peak as stated above.


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