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Did you measure them up Trustr32?

Na not yet got a set of Verniers on the weekend and I'll pull the front housings off on Wednesday night and measure them and let you know. I Have been too busy lately to get to them and I'm still waiting for my manifolds so haven't been in a rush.

Well I pulled them apart tonight and got to measuring and unless the tolerences are next to none then I think they're the same turbo's. I measured the bottom width of the comp wheels and they were 60.00mm and 60.06mm. The length of the longer fins are exactly the same at 23.35mm but the gap between the tips of the smaller and larger fins were a bit all over the place ranging from 5.83mm-6.11mm but even on the same turbo they varied. The only other thing I measured was where the wheel tapers up to the part that the nut sits on with one being 15.53mm and the other 15.6mm. I mean I dont know much about turbo technology and just how precise or not it is but both "look" the same and both comp housings fit on each other turbo with the wheels still spinning so I cant see that they are different. The only things I did notice is that both wheels have a different set of numbers/markings around the base of the fins with one having "294 A w R" and the other having "294 A C R" and one had what looked like an assembly lube and the other didnt. I aslo stumbled across another thread the other day where someone mentioned the same thing as me about one turbo having 2860 and the other 2560 and someone said that as long as they both have 707160-5 they're the same. Anyway here's a few photo's any idea's would be appreciated.

Cheers Brodie.

post-58307-0-06556000-1314270261_thumb.jpgpost-58307-0-45915500-1314270283_thumb.jpgpost-58307-0-10150000-1314270310_thumb.jpgpost-58307-0-70849600-1314270218_thumb.jpgpost-58307-0-50407200-1314270346_thumb.jpg

Sounds good so far.... disco may be able to shed some more light on the numbers

Have you compared the turbine....if not, you should

I have never done it but maybe you could get some modelling clay or similar and make impressions of one and compare to the other

Sounds good so far.... disco may be able to shed some more light on the numbers

Have you compared the turbine....if not, you should

I have never done it but maybe you could get some modelling clay or similar and make impressions of one and compare to the other

Turbines look identical and both measure the same at the base 53.03mm they also both have the same numbers "166 A 01 H"

Yeah hopefully it wont come to that but I will if i have to I guess.

post-58307-0-92587400-1314275449_thumb.jpgpost-58307-0-66253700-1314275489_thumb.jpgpost-58307-0-18625000-1314275527_thumb.jpgpost-58307-0-76832500-1314275409_thumb.jpg

Hey guys sorry to keep hassling everyone but can anyone shed a bit more light on the situation now with these measurements? Disco? Nizmoid? I'm at the stage where I think they're about as close as you'd get without bring exactly the same but id still like another opinion or two.

  • 2 weeks later...

Ok here goes...

My next turbo arrived and it has the "S" on the pn. (GT2859R - 780371 - 5001S)...This turbo however was made by Honeywell the other one which the supplier had from before, and have to pair up with (GT2859R - 780371 - 5001) was made by Allied signal.

I measured up the wheels and both measured the same, visually looked the same and even had the same numbers stamped on in the same spot.

However the comp housing on the Allied signal was visually larger (fatter) where the text is printed on to the front and just had "garrett" and M24 printed where as the Honeywell had "garrett" M24 and .42A/R and some other stuff on it....You could clearly notice a difference between size of the comp housings.

I taped up the comp inlet and outlet with duct tape and filled them with water and they both basically measured up the same

I was thinking the difference is just due to different casting, as u could feel the bigger housing (Allied signal) was thicker and heavier.

Both housings are .42A/R so does this mean technically that they should flow and perform the same even though one is physically larger looking on the outside??...Inside bore looked the same but hard to tell.

Not my pics but this seems to be the newer castings for the gtss/-9/-1

post-42272-0-10631500-1315712398_thumb.jpg

This is the older style casting

post-42272-0-47964800-1315712560_thumb.jpg

I have one of each

You can see the difference in the "hump" on the comp...the older style is definitely larger but both are 0.42A/R

Trustr32 not hijacking,.... just want to keep this info in one place

Not my pics but this seems to be the newer castings for the gtss/-9/-1

post-42272-0-10631500-1315712398_thumb.jpg

This is the older style casting

post-42272-0-47964800-1315712560_thumb.jpg

I have one of each

You can see the difference in the "hump" on the comp...the older style is definitely larger but both are 0.42A/R

Trustr32 not hijacking,.... just want to keep this info in one place

Na thats no probs at all man if this is going to become a more regularly asked question it's good to have 1 place to find answers wel hopefully anyway lol. So it's only different externally? Like the inner chambers look/feel the same?

Well thats the thing....the comp outlet at he end is the same but its really hard to measure otherwise.....Thats why I filled both with water to check the volume, which basically measured the same.

Hear this....

I did measure the depth at various points around as shown in the pic on the Honeywell (newer) casting and even though it was smaller on the outside, it actually measured deeper at some points than the other casting which was physically larger watching it from the outside, so that means the extra bulge was in fact due to the thickness of the casting itself...I would say almost 3/8" thicker around where the rectangle is printed close to the outlet.

post-42272-0-89202000-1315794006_thumb.jpg

You could clearly tell the difference between manufactures as the newer housing was much cleaner / smooth / neat than the older style gtss / -9 which everyone knows

I'm not clear how A/R is calculated, but seeing that both are the same 0.42A/R and both hold the same volume of water, even though the shape is not 100% the same internally does it mean that it will flow the same?

It should have the same comp map right?

  • 11 months later...

It's just Garrett adding a new classification far as I'm aware as they do from time to time (although, it's not exactly "new").

Could be more-so that people stocking the turbos were simply not listing them correctly after the ID tag change, given there is only one option for 2860R's for bolt-on GTR :)

For the GT Series, model GT4082SN translates as follows: GT40 = (77mm turbine); 82 = 82mm compressor wheel; S = single passage bypass turbine; and N = ported shroud.

http://garrettbyhone...identification/

Garrett-Turbo-GT-Series-Model-Designations-.gif

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