I think its time

Whimp

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Gus,

Are we talkin internal or external here?


I tried a 3071 internal on my m8 with the .86 ar and it was lazy on response.....

Pulled great on top and ran cooler but Im far too concerned with my throttle response to justify losing any to gain top end.....This could of been the .86 ar.....

I understand what you are saying with the bigger comp wheel etc... but my concern is you are still dealing with an 800cc air pump to get this thing spooled up...Once you are spooled and you have things moving I agree with everything you are saying... But The bigger comp wheel/turbo you go the more it takes to get things moving..... If not why wouldnt you run a 35 series on an m8 and still have awesome response? Im just brain storming here.... No harsh words meant....

I would also have to say that pipe pressure is very important for launch and that crazy arm pulling acceleration we all love.Although too much is a bad thing and rusults in all the evils you mention above... Not enough will not drive the turbo hard enough for my liking... I know you are dealing with many variables we do not have to deal with out here in the deep powder and high elevation....

I have had such awesome luck with the 2871-2 internal .86 ar I haven't found anything that performed better for me and what i look for in my turbos and riding style... between 5 and 14 psi... 6k to 11k in elevation....

After reading your post I would like to try the 3071 or 3076 with the smaller .64 ar on an M8...You have me thinking but there are still a few things I have doubts on......HMMMMMMMMM


Are the sleds you are building external?

Thanks
 

Wheel House Motorsports

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i ran a .64 interally gate 30 on my 700 and never had backpressure issues or climbing egts and it spooled like it was going out of style. if you have the charge system to accompany the big compressor side they can really shine then.

without the accompanying chargetube/airbox there is no way the compressor can really show you what its got going on. playing with airbox volume and design will get you big gains in bottom end especially coupled with the big turbos.
 

WyoBoy1000

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i ran a .64 interally gate 30 on my 700 and never had backpressure issues or climbing egts and it spooled like it was going out of style. if you have the charge system to accompany the big compressor side they can really shine then.

without the accompanying chargetube/airbox there is no way the compressor can really show you what its got going on. playing with airbox volume and design will get you big gains in bottom end especially coupled with the big turbos.
Whats it take, I'm listening!
 

Whimp

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Boost

Im not sure I completely agree with the air box volume and airflow... I've ran big volume air boxes..Twisted,Boondocker and small volume airboxes..OVS and I have seen little difference in performance..maybe at 20 psi and above these are much bigger factors but I have seen small differences at the boost we run... 15 psi and below.... I will agree that the larger charge tube helps with heat but I think there is a big misunderstanding with turbos and airflow on the charge side....My favorite airbox has been the Twisted which is a side entrance....most would say this is a big no no because of where the air is entering..... I do not think they realize that this is a pressurized system and only one cylinder can drink air at a time.............Its not like you are flowing air into both cylinders at the exact same time... Once cylinder drinks then the other cylinder drinks.....So if the system is pressurized then the air is going to take the path of least resistance....i do believe that air turbulance is not a good thing and the easier you can make the air flow the better but I will have to say as well that the bigger space you have to fill on the intake side has the ability to create lag.... My whole point is bigger is not always better.... You have to find the sweet spot where you are efficient and dialed to what you want out of a turbo....

Thats why I have always set up my own sleds the way I like....

And this is why its always awesome to see people trying new stuff....

I think it awesome you ran a 30 series on an M7 and it spooled lightening fast!!!! I have not been able to make this turbo spool as fast as the 28 series on my M8s.. Most will say the 30 series is a more consitant smoother power... but I like the wicked hit of the 28...... I will have to follow your advice and try the .64 ar 30 series on an m8 this year.....
 

gus bohne

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Whimp, I only use xternal gates and always on the pipes center section or tailcone.

.64 is the answer and Dooinit has run it as well as Eli on his polaris twisted sled and had a wonderfull season as he said.

Always seems to be easier to have discussions on this side,, humm guess thats why I'm doin a cat NEXT>!! for me.:jaw::jaw:

Tony, you are always right my friend. :brokenheart:

Though I do believe in airbox volume being aired to the larger side, and dont like a side entrance on a carbed sled. I find no argument with Shains success.
 

WyoBoy1000

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Doo it,
are you running a external waste, is that the difference here or does it matter and the diff is the .64

Gus and Doo it, you two are more of an all out style from what I get, whimp and myself are more of the 5-12lbs max and off and on the throttle. So just exactly what would you recommend, 28, 30 - 71,76, 84, -- .82, .64 --tail, internal, external. I am a less is more person and my riding rarely allows more than 10sec WOT usually it consists of 2 sec bursts so response is needed and as much as I can get.
 

Whimp

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I will be trying a few turbos this season for fun....

2867 will be the first ... it has better flow characteristics than the 2871 and its a sweet turbo no doubt.....

Then I will try either the 3071 or 3076 with the .64 ar and compare all of them.....

Should be a fun year!!!!
 

WyoBoy1000

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I will be trying a few turbos this season for fun....

2867 will be the first ... it has better flow characteristics than the 2871 and its a sweet turbo no doubt.....

Then I will try either the 3071 or 3076 with the .64 ar and compare all of them.....

Should be a fun year!!!!
2867 or 2876? You sticking to the internal, any head or engine work.
 

Wheel House Motorsports

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if your staying internal, i got a .64 housing i could sell you as im switching setups.

as for all out, I am far from that, just super efficient at low boost is what i shoot for. riding buddy rocks a 3071 tial .63 and external, only runs 3.3# of boost and runs right with most turbos at 7. honestly, i rarely run WOT for more then 30 seconds, mostly 10 sec max brapping through the trees. i like seeing what sort of trouble i can get into DEEP in the woods. so throttle response is paramount.


as for volume, nothing you mentioned is really "big" in my mind, nor terrible efficient. 3" mandrel bends from the turbo y'd off about a foot before the t-bodies into silicone reducers right at throttle boddies. each runner has more volume then most normal airboxes and gets stellar flow when you lay into it.


and whimp, if you ever get over bozeman, livingston way to ride we should get together and see how they stack up, compare ideas. always fun to ride with people who like to try and make everything better.
 

Whimp

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2867......

havent decided on internal or external.... I like both of them but still up in the air.... Im not sure if the external will fit with how I am building my next sled.....
 

Whimp

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Dooin-it...

I ll take you up on that!!!!!!

Just moved up here awhile back and I need to learn the country and find some guys to ride with.....

Hope I can keep up!!!!

Whimp
 

KMOD

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turbos

Hi Gus.
Listen to this guy he has by far more experience than most of us combined.

I ran a 3071X on my 925 last year, it had instant response and no lag. I run the
.64 on the hot side, this turbo has the bigger exhaust than some of the 3071s., 60mm. I'm sure that the bigger pistons helped with the response but I think it would be fine on a stock 800. (May try that by year end on a XF).
It was as high as 7-8lbs over on pipe but never detoed and pistons look sharp, this was 10-15 max boost(very fast at 15lbs)
That being said my 1200 has a 3082 and I been thinking of trying that on the 925 what do you think of that gus? to big?.
Then a 3582 on the 1200, what ar on the hot side gus? most of the 1200s I have rode were laggy on the bottom even mine with the 3082 but all had the .82 ar on the hot side.
Good discussion, all in all you cant go wrong with the 2876 on the 800 bore.
Kevin
 

av8er

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My 09 M8 Twisted extreme kit ran better with the 2871-2 than the 2876

the 2876 had too much turbo lag on low end
 

everytime5.9

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This was a good topic discussed last season as well, which led me to the 2876 Tial. I understand all the concepts which led to my purchase but the best way is to compare side to side. While it did spool good and it provided a very linear power curve, i think i would still prefer a smaller GTX 2867 series over the larger GT30 for personal riding preference. But like anything its a preference, same as light tip vs heavy tip weights... Should be a good season we have quite the assortment of these turbos running around. 2871-2876-3071-3076.