turbine characteristics

P

Ph4tty

I'm nobody
Joined
Jun 28, 2007
Messages
1,090
For an easy example we'll use a 62mm. Compare the characteristics of the 62 with the 65, 71, and 74 mm turbines used by II.

I've heard the 65 spools quicker than a hx35, the 71 will lag but cool better on top, while the 74 cools as well or better while offering a broader powerband.

Or another example could be a super 66 vs silver bullet vs FI 66 SB vs k31,...

Just someting I've been trying to get my head wrapped around. And yes I did have to include FI :fish: :hehe:

Or the gt4088 vs gt3788 :fish:again :hehe: I looked at garrett's webpage and the bigger turbine increased the pressure ratios and the rpms, but the lb/ min looks pretty close.

And on an unrelated note- did you know you can get a stainless housining for a hx35 and hx40?? These guys are almost down the road from here too :rockwoot: http://www.timsturbos.com/SSTurbine_Housing_-_MHI_Inlet.html
 
Ph4tty said:
Or the gt4088 vs gt3788 :fish:again :hehe: I looked at garrett's webpage and the bigger turbine increased the pressure ratios and the rpms, but the lb/ min looks pretty close.
Click to expand...

That's easy...while I don't know the turbine specs on the GT3788R (it's not listed on the Garrett site other than a "stage 3") I do know about the GT4088R.

The 4088R is a 11 blade, 77mm Exducer turbine wheel, I don't know where the S300 wheels are measured, so this ones bigger regardless! I've ran it in a .68A/R, and .85A/R housing...spool isn't great, but once it lights, you're off! Sounds similar the the LDP wheels the S300's use. Hopefully I'll get my fueling straightened out and spool will get better!

I haven't played with a GT3788R, but I have with a GT3782R...next size smaller. They use a .89A/R housing IIRC, but I don't know the wheel specs. It spools great...I would guess the Stg III is similar to Stg II in spool, maybe a bit later! From talking with member "Hammer," it runs out of steam on the top end...I can't say that about my GT4088R. It keeps pulling until I let out above 115mph!

Chris
 
Smokem said:
Most Garrett base turbochargers use too large of a turbine to compliment spool-up, it just comes down to sizing the wheels properly for the fuel and AR.
Click to expand...

I know we've had this discussion before...and now I tend to agree! Garrett did their homework with the "Stage I, II, and III" but they overestimate their ratings on a 12v. Still, I think I'll like this charger once I get the rest of the truck squared away.

Chris
 
Signature600 said:
I know we've had this discussion before...and now I tend to agree! Garrett did their homework with the "Stage I, II, and III" but they overestimate their ratings on a 12v. Still, I think I'll like this charger once I get the rest of the truck squared away.

Chris
Click to expand...
I thought I saw that charger for sale somewhere?
 
So the turbine on my ps64 is a high pressure wheel, the 71 wheel is a low pressure wheel, then is the 74 a high pressure wheel? How about the 73.4/80mm or 74.3/83.4mm fi wheels being discussed on the s366 thread? How does the different trims effect performance?
 
trik396 said:
I thought I saw that charger for sale somewhere?
Click to expand...

Not mine...but how much you offering??:hehe:

Rods said:
So the 4088 is 88/77 on the turbine ??
Click to expand...

I'm not positive Rod...without pulling the thing, I'll just retract what I said earlier, and say it's 77mm "somewhere" I really hate to pull that tihng just to measure it!

Chris
 
What is boost creep as discussed above? Would this be when the wastegate can't support any more airflow so it must go thru the turbo and then cause the boost to go higher and higher?
 
GOT-Torque said:
What is boost creep as discussed above? Would this be when the wastegate can't support any more airflow so it must go thru the turbo and then cause the boost to go higher and higher?
Click to expand...
Yes. The wastegate can't flow enough so the drive pressure increases causing a small amount of boost; hence 'boost creep'.
 
joefarmer said:
87.18 or ~88mm for a 78 trim.
Click to expand...

How's that figured...I thought I knew, but I keep coming up with something different.

Of course since the truck is down, I can measure it for you once I pull it off there!

Chris
 
Can't you just use a manual boost controller to minimalise boost creep?
When you're talking about the ss housings, are you talking about htt?
And what is this loophole you're refering to?

:pop:
 
From the turbo I have now I feel usen alot bigger turbine wheels with small housings do pretty good coupled with smaller inducers close to the Gt40/88 even usen a mid frame charger mine is lit b4 2000 rpms and gets 1400+ @55lbs on the road with M6.5 and 1200 on the trac with homemade water system
 
You must log in or register to reply here.
Top