turbo identification/codes

i am wanting too know how do some of yall identify turbochargers. 4 examp., the Greddy turbo kit 4 my car is a TD05H-18G. Ive heard of the T3/T4 and so on but i dont understand the lit on them.

TD, TC = Mitsubishi

K = KKK

T = Garrett/AiResearch

# first = Schwitzer

HC = Holset

so does that mean Mitsu makes Greddy's turbos? Or Stingin Si's turbo at least?

Originally posted by buh_buh
so does that mean Mitsu makes Greddy's turbos? Or Stingin Si's turbo at least?


Greddy uses mitsubishi turbos

i have been trying to figure this out for a little while now as well. what i want to know, is what does the number part have to do with it? what makes it a t4 versus a t25 versus a t76? is it boost, spool up time , physical size or what?

Originally posted by b16a3sol
i have been trying to figure this out for a little while now as well. what i want to know, is what does the number part have to do with it? what makes it a t4 versus a t25 versus a t76? is it boost, spool up time , physical size or what?
good ass question

those #s are refering to the size of the compressor and turbine. A t3/4 turbo has a t-3 turbine thats smaller and spins faster reducing lag. The compressor is a t-4 thats bigger, so more air is sucked in while less gasses are used to turn it.



Now I can't remember if those #s are taken by the physical size of the turbine or the amount of air it's capable of moving.

Originally posted by b16a3sol
i have been trying to figure this out for a little while now as well. what i want to know, is what does the number part have to do with it? what makes it a t4 versus a t25 versus a t76? is it boost, spool up time , physical size or what?


it's just a series designator. the larger the number, the more it's capable of flowing. the numbers you used are based on Greddy/Rotomaster/Rajay/AiResearch turbos.

T2 series are the smallest, with T3 next, then T4.. T5... T6... blah blah blah. T25 is obviously smaller than a T28. some of these designators were taken over by Garrett when they bought out the other brands and consolidated their lineup.

it's all based on it's airflow capability, but there are T3's that you can buy that are generally named "T3", but have different wheel trim sizes, increasing it's output or efficiency. many turbos are built to OEM requirements, thus having a lot of turbos all based on one design, but slightly altered to meet the OEM's requirements... T3 for example: T3's are used by Saab, Volvo, Ford, GM, and Nissan to name a few. Saab, Volvo and Ford all use the T3 as designed by Garrett... they may have different trims to meet their purpose, but most parts are interchangeable. Nissan on the other hand used T3's but have a different exhaust and flapper valve design, which arent interchageable with any others. they even stamped their name on the turbo compressor housings.

it's hard to squarely identify a turbo without knowing and seeing lots of them before.

i am starting get it a little i think. a car running 1.6L at 8 psi and 6000 rpm is going to need more airflow than a car running 2.8L and 6000 rpm at 8 psi. but a 1.6L at 8000 rpm at 8 psi would start to equal a 2.8L at 6000 rpm at 8 psi, thus making the same turbo suitable for two applications. so do they just classify them by the amount of airflow they can run at a certain range of boost or what? and if so, is there a table i can look at somewhere that would be able to tell me what the specs are for a turbo with a certain classification? with that kind of information anyone should be able to figure out what size turbo they need by using their displacement and redline to find out what turbo fits, helping to remove a lot of the guess work. just my thoughts, please tell me where i am wrong and add anything, because i want to learn about this.

there is air flow graphs for turbos. You can find them at technical turbo web sites (retailers, manufacters) and with some math formulas you can find what size turbo is the best for youe engine. There was an article in SCC a while ago, otherwise I'll post it when I find it.