925 big bore

deaner · Mar 16, 2014

Just more of RKTs snake oil. A turbo makes up for the loss of barometric pressure when increasing in altitude. The turbo might have to work a little harder to maintain a certain psi as you go up in elevation, but pretty sure any turbo kit builder worth their salt takes that into consideration so that the turbo is near peak efficiency at the altitude the kit is designed for.

Im no engine expert, but think I have a basic understanding of things. Your BS sales pitches get old Kelsey.

Vance Matheson · Mar 16, 2014

RK Tek said:
Why will a turbo maintain HP at elevation?? Are they running different air?

I think this is a HUGE misconception that maybe we can clear up.

There are MANY factors/variables that determine what a turbo will and will not produce in terms of power ..MANY!!

a GOOD 925 kit will equal a 9PSI Boondcoker boosted PRO at 8500ft in terms of power.. and the Boondocker Pro IMO, makes a good of power as ANY of the other turbo kits..

8PSI and 224HP.. maybe good on a dyno but remember turbos on dynos do not have a calibration factor.. So, be careful of elevated turbo HP claims when on a dyno..

A good 925 BB WILL make 200HP on pump gas at sea level.. and that will equate to a very good running sled at any elevation!

i might be wrong but wont the the BB lose HP per thousand feet of elevation...like 3 to 5 or something.

Vance Matheson · Mar 16, 2014

Deano670 said:
One of our 925 av gas cats in action. Has turned out to be a very sweet package for our customers. Mr Linderman has made many smiley faces here. Keep in mind summer time is the time to build. Pm me or call 780 986 6370 for more details.

Thank you

Deano

IMG 3052 - YouTube

wicked sled dean...makes me want one

RK Tek · Mar 16, 2014

dgiles said:
Ok, maybe I need a good lesson on turbos on sleds, but I do understand turbos on planes and I am pretty sure the concept is the same. More dense air allows more fuel and that allows more HP. Naturally aspirated engines go up in elevation and with less available air density, you get less fuel and less HP. Pretty basic. On a turbo with a wastegate, you set what PSI increase you want to run (on planes its manifold pressure) and the waste gate regulates that pressure to keep it constant. As you climb up into less dense air, the waste gate closes more to allow the turbo to maintain the pressure, hence maintain HP. Am I incorrect on this statement? As you telling me that a if you had a 200 hp bigbore at sealevel and a 200hp turbo and took them to 12,000 feet, they would both still be equal in hp?[/QUOTE]

Yes, very close.. The air density remains the same for the turbo at elevation as it does the N/A sled..

NOW, if you adjust the boost pressure as you climb in elevation, you have the ABILITY to re-claim some of that lost power.. but adjusting nothing and going to elevation, the turbo WILL lose power like the N/A engine.. The air is the same!!

Now, given that fact, the big bore, AT ELEVATION, can re-claim some of that lost power via a compression increase so, the 3% loss factor goes out the window because that figure is based on changing NOTHING with the engine and just going to a higher elevation... so that 3% factor is surely reduced with ac compression ratio increase.

With a turbo, generally, you do not change the compression ratio for elevation increases.. so you have "sea level" components in play and the boost level will automatically DECREASE as you increase elevation unless you manually increase it.. If you start in Denver in your turbo truck and drive to MN.. your boost level will automatically INCREASE and the vice versa.. if you drive from MN to Denver, you will see a loos in boost pressure..

So, there are methods to keep the n/a engine from losing as much power as it normally would with an elevation increase and there are methods for the turbo engine as well.. Just different methods.

make sense?

neilsleder · Mar 16, 2014

Throttle-Junkie said:
I was undecided what I was going to do with my 2013-153 and after playing with boost for a little while on another sled Deano had me sold on a BB. I couldn't be happier with my motor Deano built me. These 925's pull like a freight train! Deano had my sled dialed in for the hills when I picked it up no guessing games with numbers or clutching!

As for the price it is very reasonable IMO. Your getting a top notch product and top notch service on a kit that is build tested and tuned in areas most of us ride!

I highly recommend anyone looking at a BB or mods to call Deano!

Next chance I get to ride I'll throw together some video.

Thanks again Deano!!!

Sent from my iPhone using Tapatalk

Seen your sled at Deano's shop nice ride!

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fredw · Mar 16, 2014

Comming from a guy that has a 880bb and a 800turbo, and setting up his own clutching... I can pull 5 grams more of pin weight at 5 lbs boost than I can pull on the bb...

Track speeds with the same track are 58mph to 70mph on the turbo sled... It's a no brainier once you felt them both :nono:

acesup800 · Mar 16, 2014

RK Tek said:
boost level will automatically DECREASE as you increase elevation unless you manually increase it.

Not if you have a properly working wastegate. Turbo's will spool much more PSI than required, so a wastegate is required to dump excess pressure and regulates to maintain say 9lbs. Some wastegates are manual and like you said, as you increase elevation, you will lose PSI, but all you do then is close the wastegate down which moves the pressure right back to what you originally asked for. The only way for a turbo anything to have less Hp at elevation vs sea level is if the turbo is undersized and at some point can no longer maintain the boost setting you are asking for.

Don't get me wrong, I am one of your customers with a 925 kit and love it, but against any PROPERLY tuned turbo, I have no chance.

Throttle-Junkie · Mar 16, 2014

neilsleder said:
Seen your sled at Deano's shop nice ride!

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Thanks it's starting to come together, will be back at Deanos shop over the summer I am sure (skid & and a few more goodies) maybe we will catch ya @ The shop one day..

Cheers

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CamoKVF700 · Mar 16, 2014

I have a manual waste gate and hit 24 lbs at sea level and 18 lbs at 5500 feet. It's a GT25 on an 800cc motor so a little big. Use nitrous to spool it out of the hole. Lol. But a turbo is free hp and the harder you load it, the harder it will pull... And forever.

Sent while wishing I was on my snowbike

Vance Matheson · Mar 16, 2014

dgiles said:
Not if you have a properly working wastegate. Turbo's will spool much more PSI than required, so a wastegate is required to dump excess pressure and regulates to maintain say 9lbs. Some wastegates are manual and like you said, as you increase elevation, you will lose PSI, but all you do then is close the wastegate down which moves the pressure right back to what you originally asked for. The only way for a turbo anything to have less Hp at elevation vs sea level is if the turbo is undersized and at some point can no longer maintain the boost setting you are asking for.

Don't get me wrong, I am one of your customers with a 925 kit and love it, but against any PROPERLY tuned turbo, I have no chance.

thats what i thought.

Fast6seccamaro · Mar 16, 2014

Deano670 said:
One of our 925 av gas cats in action. Has turned out to be a very sweet package for our customers. Mr Linderman has made many smiley faces here. Keep in mind summer time is the time to build. Pm me or call 780 986 6370 for more details.

Thank you

Deano

IMG 3052 - YouTube

Hey that's my sled.....and me! Lol

little history on my sled and my experience with dean @ Mad Motorsports and Brent @ arctic edge. I bought my 13 last year and had several referrals from people to contact dean about a big bore. After talking it over with dean and knowing the quality of the work coming from Brent we decided that the 925cc was the way to go. I was busy with work so dean put the sled together in good time and quality work. I only got the sled out 2 days last spring and 4 days so far this year. This sled has been a total "pull and go" package! The sled is in "as delivered condition" from dean with the exception of small clutching which is to be expected on a sled to sled basis! I'm very happy with this package and wouldn't hi satiate to spend money with both shops again! A+ service!!!

as far as the big bore VS turbo....I won't get into that! The big bore was the right choice for me and my riding! The hill in the video is as big as I usually ride, I usually hide in the creeks and trees! I have all kinds of race cars from a outlaw 10.5" BBC twin turbo on alc, BBC f2 and f3 pro chargers, 900RWHP nitrous street cars. It's not always the hp the wins you the race but how you can use it! One day I'll have a turbo sled but very happy with my tree riding BB

Fast6seccamaro · Mar 16, 2014

Vertical-Extreme said:
nice, Were you guys in fernie on Monday?

Ueah, that's was a buddy and I. Why? Did you see me in a embarrassing stuck or bone head move? Lol. Still learning this sled! Lol

Vertical-Extreme · Mar 17, 2014

Fast6seccamaro said:
Ueah, that's was a buddy and I. Why? Did you see me in a embarrassing stuck or bone head move? Lol. Still learning this sled! Lol

Haha, no,no I was the other guy in the parking lot with my little guy with me. good to meet you guys!

Fast6seccamaro · Mar 17, 2014

Vertical-Extreme said:
Haha, no,no I was the other guy in the parking lot with my little guy with me. good to meet you guys!

Good show! Looked like the little fellow had a blast, when we came around the corner and passed you on the trail he had a ear to ear smile! Lol. I'm sure the truck ride on the way home was either full of excitement or very quiet with a sleeping little boy! Good meeting you too!!!

925 big bore

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