MyE28.com

[QUOTE="345is"]264 cam in M106. turbo Cold side .50 a/r Hot side .83 a/r[/QUOTE]

Did you change your manifold to accept the new turbo??

[QUOTE="Jesse "]Dan - What controls system are you running????? What rear end gear are you running???[/QUOTE]

Im running the Miller MAF conversion kit, and a 3.25 diff

Todd Its a t4 comp. with .50 A/R t3 hot side.

Todd what size injectors are you running?

[QUOTE="345is"]Todd Its a t4 comp. with .50 A/R t3 hot side.

Todd what size injectors are you running?[/QUOTE]

But what are the compressor wheel and turbine wheel?

I currently run 65lbers and MS. Previously I have run 30, 36 and 42lbers with Motronic and our chips.



[Edit by TCD on [TIME]1137935014[/TIME]]

[QUOTE="Jesse "]Dan - What controls system are you running????? What rear end gear are you running???[/QUOTE]

[QUOTE="345is"]
Im running the Miller MAF conversion kit, and a 3.25 diff[/QUOTE]

Okay so........now I'm going to assume that you are running the 745i Motronic stuff as your base control system???

yes

i think u guys skipped over the most important thing, THE EXHAUST MANIFOLD SUCKS
the collector todd mentioned before is almost the same size as one of the ports on the head (which would make it much smaller than a T3 turbine port )
, the stock k27 turbine is matched to this port ( for quicker spool up ), so for the factory boost levels this setup is perfect, but when your talking about going 3 times more boost, not even close .
theres where all your backpressure is.
345is, r u still using the same manifold? or hav u made any mods to it ?
because a stock T3 wont bolt onto it.

[QUOTE="papajetta"]i think u guys skipped over the most important thing, THE EXHAUST MANIFOLD SUCKS
the collector todd mentioned before is almost the same size as one of the ports on the head (which would make it much smaller than a T3 turbine port )
, the stock k27 turbine is matched to this port ( for quicker spool up ), so for the factory boost levels this setup is perfect, but when your talking about going 3 times more boost, not even close .
theres where all your backpressure is.
345is, r u still using the same manifold? or hav u made any mods to it ?
because a stock T3 wont bolt onto it.[/QUOTE]

Good point. I think you may be correct, but it begs the question why they did not just go with a K26 unit instead. If they tried to make the K27 spool up fast, I'd say they didn't do so well. BTW you must remember, gas path restriction is due to the smallest cross sectional area encountered in the path. Even though say the T3 has a bigger inlet, it skinnies-down in a hurry inside the turbine housing. It's a good observation, but I'm not sure if that's the whole enchilada.

[QUOTE="papajetta"]i think u guys skipped over the most important thing, THE EXHAUST MANIFOLD SUCKS
the collector todd mentioned before is almost the same size as one of the ports on the head (which would make it much smaller than a T3 turbine port )
, the stock k27 turbine is matched to this port ( for quicker spool up ), so for the factory boost levels this setup is perfect, but when your talking about going 3 times more boost, not even close .
theres where all your backpressure is.
345is, r u still using the same manifold? or hav u made any mods to it ?
because a stock T3 wont bolt onto it.[/QUOTE]

[QUOTE="Jesse "]Good point. I think you may be correct, but it begs the question why they did not just go with a K26 unit instead. If they tried to make the K27 spool up fast, I'd say they didn't do so well. BTW you must remember, gas path restriction is due to the smallest cross sectional area encountered in the path. Even though say the T3 has a bigger inlet, it skinnies-down in a hurry inside the turbine housing. It's a good observation, but I'm not sure if that's the whole enchilada.
[/QUOTE]

I think your right Jesse, I will find out when I dyno it if the manifold makes that much difference or not. But what you said about the turbo skinnying down in ahurry is exactly what I was thinking when I used the stock manifold with a t3 ehaust housing, The majority of back pressure between the exhaust valve and the turbo is from the turbo. not the manifold.

well they all skinny down pretty quickly, but u have to look at it a little closer,
remember, having a:
0.5 a/r turbine is not the same as a 1.5 a/r turbine.
at least according to corky bell this can make a big difference in spooling time and in moving your power from the middle to the top of the rpm curve
does anyone know the a/r ratio for a 745i k27 turbine housing?

i'm pretty sure it's a tasty number --

MILLER -
do you sell just the adaptor plates to adapt a T3/4 on the manifold? I don't need anything else but that.

Really? What A/R is the TO4? The SAAB turbos I want to run are .42s and some book I read said you can half the A/R of a single to aproximate the ones for twins.
I really wish there was some equation for figuring A/Rs. I'll work on one. :p

[QUOTE="TCD"]So what are the specs of the compressor and turbine? T3 with a .83 a/r on a 3.4L should spool like, immediately!

Is this a Chinese Garrett copy sold by SS Autochrome?[/QUOTE]

[QUOTE="altus22"]Really? What A/R is the TO4? The SAAB turbos I want to run are .42s and some book I read said you can half the A/R of a single to aproximate the ones for twins.
I really wish there was some equation for figuring A/Rs. I'll work on one. :p [/QUOTE]
The turbine A/Rs are simply the ratio of the cross sectional area of the port at a given point relative to that points distance from the center point of the scroll. A T3 and a TO4 can have the same A/R but the TO4 will flow significantly more volume as it is simply bigger.

[QUOTE="Tjn182"]i'm pretty sure it's a tasty number --

MILLER -
do you sell just the adaptor plates to adapt a T3/4 on the manifold? I don't need anything else but that.[/QUOTE]

I could posibly sell you just the adapter plate, but I would have to talk to you more about how it works first. do you have the turbo you are going to use yet? and how long until you want to mount it? let me know.

Hey 345is,
Can you post a K27 dyno vs T3/T4 hybrid? That would be really interesting to see? If Im I wrong I guess the proof is in the pudding. Since you got the dyno plots to compare. I hope the dynos are just the turbos compared, with the same fuel/ignition systems, and hopefully from the same dyno.

Look forward to the results,
Thanks,
RussC