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Alright I know I said Im happy running the 195 tune and I have no interest in any more but.......... it seems like I should at least try the 205 since I have it on my flasher.... so I have a couple of questions to anyone that has experience with these tunes.

-How do I do this waste gate adjustment?

-If I go back to the 195 or even the stock tune for that matter, does the wg need to be re adjusted?

-assuming I will need to add more weight to the clutch

-If I don't do the wg adjustment what happens.... loss of power or will I get a check engine light? On that note... if I was losing pressure thru the wg with the 205 or even 195 tune would I know it?

Again, Im very happy with the 195 tune, its just hard to ignore the fact that ive got another 10hp available at the push of a button :RevDude:
 

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Not all sleds needed the waste gate adjustment. Flash the 205 tune and try it. I assume you have a flasher? If so log boost and rpm. If there was duty cycle left in the waste gate it will make more boost and power. You may need to add weight just depends on what your rpm is at now.

Going back to the 195 will be fine as the duty cycle will lower target boost.
 

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Alright I know I said Im happy running the 195 tune and I have no interest in any more but.......... it seems like I should at least try the 205 since I have it on my flasher.... so I have a couple of questions to anyone that has experience with these tunes.

-How do I do this waste gate adjustment?

the wg rod is located below the manifold. *if you feel comfortable doing on the sled...you must loosen the locknut...then use something like a needle nose vice grip to pull the rod towards the muffler side.there is a clip on the muffler side end which holds the wg rod end (turnbuckle) to the wg door pin...once clip is removed, you can feel the turnbuckle and half turn it and feel that.. next is getting the clip back on...the difficult part...you need to slightly spread it for it to grab on the pin...and its small..I found a forked angled screwdriver to be perfect

-If I go back to the 195 or even the stock tune for that matter, does the wg need to be re adjusted?

yes

-assuming I will need to add more weight to the clutch

not necessarily...you might gain a few rpms ...although dave has prescribed the peak power...

-If I don't do the wg adjustment what happens.... loss of power or will I get a check engine light? On that note... if I was losing pressure thru the wg with the 205 or even 195 tune would I know it?

there would be no benefit..maybe even detriment

Again, Im very happy with the 195 tune, its just hard to ignore the fact that ive got another 10hp available at the push of a button :RevDude:
 

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Old grampie ... you already have one on the turbo... you only might need adjustment if you were to re program it... non turbo won't have
 

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boost junkie
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I bet he is asking about a BOV, blow off valve is not oem

at stock boost it is not a necessity

a good BOV kit will use re-circulation

to keep snow out of the valve

if you dont want a waist gate, to turn off... just pull the hose off the actuator to get more boosties :blink:
 

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boost junkie
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no boom, just a overboost code with the dreaded CEL

the bosch ecu is almost bulletproof
 

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Stock ECU will only pull 6* of timing so I wouldn’t say bullet proof. I’ve seen 2 blown motors, one was ring lands the other had a chunk of cylinder missing. I also heard a rumour of two motors breaking rods recently but that’s all that is so far.
 

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hmmm.. many miles on them tuned? hopefully bad gas was the culprit or something simple like that... Hopefully these were just one off isolated issues and that there isn't more of these stories to come down the road for the 900T world... time will tell I suppose
 

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boost junkie
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when the ecu sees more boost (tourque) than requested you get the overboost code

and a CEL @ 4000 max rpm I would call that bulletproof

now a tune that request 21psi will not likely throw a overboost code

now if you program the tune for high octane fuel and use pump or bad fuel

its not the ecu fault it cant pull enough timing

as I said oem tune is absolutely bulletproof

6* timing is a huge change and if the aftermarket tune is correct

the ecu would protect the motor even with bad fuel
 

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The danger is aggressive tunes with improperly adjusted wastegates on marginal fuel quality. The Bosch ECU is a nice piece and the stock tune makes the engine near bulletproof. The danger is when the consumer thinks an aggressively tuned 900t with overtightened wastegate and marginal fuel quality is bulletproof. My experience is most do not understand the complexities of the tunes and fully understand what adjusting a wastegate ultimately has an effect on other than more power. That is why I recommend anyone buying a tune fully understand what is entailed for wastegate adjustment and fuel quality. Listen closely to your tuners recommendations an adhere to them to the letter. And for those thinking of adjusting tunes etc. On their own, make sure you fully understand what you are doing as if done improperly it can at best case scenario destroy your pistons, worse case scenario destroy the entire engine. I have seen first hand what happens to pistons on all three cylinders when using a tune and basically locking the wastegate. In this particular case it was maptuner X with the injector tune but any tune could result in this with low grade fuel and locked wastegate from overtightening. We are all pushing the design limits by putting a tune in these sleds to increase the power output well beyond its design. Just hate to see anyone with any tune suffer costly engine damage so please be smart and if you dont know something, ask your tuner. They can be a wealth of knowledge and if you dont care to learn just set up your sled to the exact tuners specs and respect his or her octane rating for the tune.

Hope this helps...
 

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is the ecu not capable to pull enough timing or boost here? or is it more the way it was tuned by the tuner? This is something we 3rd party owners are going to have to watch carefully when choosing tuners. if there is not some sort of safety put into place with the tune for getting crappy northern fuel than it can have all the HP it wants but its no good to ya with a blown up engine.. these things aren't cheap to fix. WOW note taken here...just asking as we are all learning this new package and want to be better educated in the subject to make the best decision when its time to lay down hard earned money for a tune..
 

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I have data logs of a 220 tune pulling 4 and 5 degrees of timing running the recommended 93 octane with some booster in it. The stock map sensor Is only 2.5bar Are you only running 21-22lbs of boost when you crank the wastegate shut? If not you can see what happens? What about tunes that are ran for a couple passes in a controlled environment then released without real world testing? What if you’re adding components like full exhaust and CAI without testing? If you ask your tuner the right questions and sift through all the information it will all start to make sense.
 

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Well with all this information absorbed I've made my decision to stick with my 195 tune. I know nothing about duty cycles etc, and even if I data logged I wouldn't know what to look for...
my gut said not to get into waste gate adjustment so I'm going to listen to it.
Here's hoping that the 195 is in the safe zone and I get through the season without anything going boom. After that I think I'll be selling it, and spring checking another 850... I was more than happy with the way my 2 850s ran out of the box without any fear of a warrantyless engine failure. Those pics of blown pistons make my stomach turn.... kind of defeats the purpose of owning a fourstroke if reliability is in question ????
I might have a flash tuner and clutch weights for sale this spring if anyone wants one.
 
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