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Good post, this should set some people straight....
Its a shame most of the people in here won't understand what they're looking at. A lot of turbo selection and 'myth' is based on hear-say instead of facts like these graphs...
which is why I'm going to take it upon myself to explain to people a little bit... I hope notec doesn't mind.
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dragracemyz24
Monday, January 02, 2006 6:45 PM
^^ he is correct. I have burnt up two of them allready. Great turbo for street use and low boost . But anything above 8 or 9 psi , I would upgrade to a t04e 57 trim as stated above.
I dunno how you burnt up 2 turbos... but I'd put my money on bad luck, bad oil supply, or crappy turbo(s), or a crappy rebuild(er).
a t3 super 60 will have the best spool characteristics of any of the above, and make more power HAPPILY up to about 16psi or so if not more. 20 is right around where you hover above peak efficiency and are just heating up air before it gets into your engine. I'll elaborate on the images posted by notec to illustrate my point. Thanks to notec for doing the work for me =)
as notec stated, the dots are as follows:
Red dots = 5psi
Blue = 10psi
Green = 15psi
Orange = 20 psi
the dots at each boost level are in increments of 1000rpm starting at 3000 from left to right.
A compressor map reads like a topographical map, but instead of elevation, it shows efficiency. The middle most island is where the turbo makes peak efficiency, surrounding islands are progressively less efficient. The dashed line all the way to the left is the surge line... if you're over that line at 3000rpm or so.. you shouldn't be using that turbo period. If the dots fall off to the right the turbo is too small. If your dots don't go thru the peak efficiency island, the turbo isn't proprely matched for your boost level.
This image shows a t04e-57 trim turbo on a 2.4.
looking at this map, you can clearly see that this turbo is WAY TOO BIG. The dots at 5psi are barely on the graph at all which means you'd probably see little to no power increase since you won't be spinning the turbo fast enough to generate boost
at 10 psi you're dangerously close to the surge line at 3000rpm, and you're still barely on the graph since this turbo is designed for higher rpm or larger engines.
at 15psi you're over the surge line substantially
at 20psi you're even further into the surge area, a very bad thing. and at this point, the turbo is beyond its peak efficiency.
This turbo would be better suited on a larger engine or one that spun higher RPMs (requiring more cMF (the numbers across the bottom... corrected mass flow... aka how much air ur engine can flow in lbs/ min))
In this picture, we have a t04e-50 trim
Again the same as above takes place... You can clearly see from the oritentation of the dots that this turbo is better suited from a larger displacement, or a higher revving engine. The 2.4 cannot flow enough air in order to use this turbo effieciently. Using this turbo on a cav that doesn't spin higher rpm is stupid and basically a "my cock is bigger than yours" move. You will sacrafice spool, and will not make as much power as a smaller turbo at the same boost level. Case in point:
t3 super 60
as you can see, all the dots are on the graph in relatively good positions. This is what we want to see
as you increase boost, the dots move, but within the area that was mapped on the turbo.
5 psi is a little low for this turbo, but will be ok
10 psi you'll be making about 230whp if not slightly more or less depending on individual set ups.
15psi you'll be making quite a bite more power i'm not sure exactly, probably in the neighborhood of 270 to 280 or so but as you can see the turbo is still happy with a little bit more head room
at 20 you're over the surge line which again, you want to avoid like the plauge. 20psi is too high for this turbo.
keep in mind, this turbo will be FULLY SPOOLED by 3000rpm at the latest.. give or take 200rpm remember more boost takes longer since the turbo has to spin faster in order to generate that boost.
I can't even remember how many discussion/ arguments/ questions have been brought up about the t3 super 60 being a good match or not but frankly, on a street driven, mildly modified or otherwise stock engine the t3 super 60 is THE BEST CHOICE FOR 8-16psi (garrett turbos anyway)
if you want to boost higher, there's other turbos that would be better suited but a good rule of thumb is 10psi is kind of pushing engine internals and drivetrain limits. So keep this in mind when choosing what you want to do.
my buddy's turbo ecotec with a t3 super 60 runs 13.5 @ 105mph on 9psi of boost. which has plenty of room for improvement.. but launching is a bit difficult. The car makes 225whp and 250wtq
