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cheers for those prices. Although they claim to be a 'bolt-on' kit, is it still quite a time consuming job? I realise it will depend on the workshop etc., but are we talking 2 hours, a day...longer??

i say if u have a weekend free, and the right tools you could do it :D it many take you 2days :) but it will be free. You will be amazed what you can do when you put your mind to it ;)

the basic tools you would need i would say be a good socket set, plus jack and car stands, and maybe 2friends to help you out :)

The beauty of trust turbos is that they come on boost quickly, unlike 'old school' bush bearing turbos.

Added to the quick spool is that they work better at high boost, in that they dont wear as quickly as BB turbos.

Most HKS BB turbos are recommended by HKS to run between only 0.9 and 1.1 bar according to the goodsmaster catalogue. They do of course work well at alot higher boost, but the longevity is effected (according to a Jap mechanic I had a chat with once)

EDIT: 2xGTRS on GTR = LAG, big time.

The Plain bearing T517Z's are far less reliable than the GT style ball bearing turbos.

Plain bearings have far higher friction than ball bearing = lots more heat.

The Trust turbos are not water cooled = more heat.

More heat = more wear.

More wear = less time before failure.

On top of that the ball bearing turbos response time is faster over the exact same plain bearing design.

Also the lower the boost pressure the better. If I can acheive the same horsepower at a lower boost why wouldn't I go that way. Longevity is effected on everything with higher boost not just your turbo, this is true of any turbo including the trust units. Boost = heat.

Having said that the guys at Trust have chosen good matches of housings, compressors and turbines despite the fact that they are done on the cheap, they don't pass on the saving to you though.

I understand all the points you have made, and they do apply 'theoretically' on their own, but once applied to the context of the posts above, they start to fall apart...

The Plain bearing T517Z's are far less reliable than the GT style ball bearing turbos.

Where did you get that info from. I have spoken to a couple of prominant tuners in SA that both SWEAR the trust turbos are more reliable than BB. I have seen trust turbos that have had alot of abuse without any reliability problems. I have seen a BB turbos that have shown signs of wear (CHRA getting loose) after 10,000kms.

Plain bearings have far higher friction than ball bearing = lots more heat.

The Trust turbos are not water cooled = more heat.

More heat = more wear.

More wear = less time before failure.

This may be true if you were comparing two BB turbos or two bush bearing turbos one with and one without water cooling, but otherwise you just arent comparing apples and apples.

The bush bearing is designed to run without water cooling, the BB is designed to run with. Agreed if you were to water cool a bush bearing it MAY last longer, but you cannot compare the life of the two without actually doing tests.

On top of that the ball bearing turbos response time is faster over the exact same plain bearing design.

The 'exact' same bearing design???? They arent the exact same bearing design.

Yes BB design works well, but from what I have seen, bush bearings have come a long way. If you had the same spec turbo and used two different CHRAs, you may have a valid point - but at the end of the day, they arent the same spec. The GTSS works well, so does the T517

Also the lower the boost pressure the better. If I can acheive the same horsepower at a lower boost why wouldn't I go that way. Longevity is effected on everything with higher boost not just your turbo, this is true of any turbo including the trust units. Boost = heat.

Very true, but you also need to take into account MANY other factors, such as the compressor efficiency, etc, etc, etc. But still, if a turbo is 'limited' in its ability to make boost (due to longevity reasons) why wouldnt you buy a turbo that has extra potential, ie, can be boosted higher without having to worry about the turbo needing to be rebuilt.

If you had a choice of two turbos, both flowing the same amount a 1 bar whilst being 80% efficient. Both of the turbos will flow the same amount of power at 2 bar, with 75% efficiency, but one will last 5000kms, the other 20000kms - which would you choose. Of course the one that is capable of producing more power with minimal reliability issues when compare to one that WILL have reliability issues.

Having said that the guys at Trust have chosen good matches of housings, compressors and turbines despite the fact that they are done on the cheap, they don't pass on the saving to you though.

Hmm, when you consider that you can now buy a performance turbo, that lasts well, and works very well for under 3k bolt on kit, all gaskets, adaptors, hoses, clamps, lines etc, I dont think they are bad at all. Especially when compared to what if available for a few dollars less in generic turbo form that just doesnt give anywhere near the same performance. After all the heart of a turbo charged car is the turbo - a good one will keep the smile on your face every time you drive the car.

Once you take into account duty, gst, broker fees and shipping, importing a HKS GTSS turbo kit is more expensive than buying a trust T517Z kit that is being retailed in australia for under 5K.

GT turbos are good, no denying it, you do need to keep the boost down if you want to get a long life from them, they are FAR more expensive to rebuild than bush bearing. As long as you buy a performance setup for the style of driving you want (street, drag, drift etc) you will be miles ahead of someone running a generic turbo.

GTSS and T517Z are both excellent turbos, just dont rule out the T517Z because they have bush bearing instead of BB. They are bloody awesome turbos.

they dont compare, they are cheap generic turbos, not performance turbos.  Good if you want a cheap upgrade, not so good if you want to realise the best from your car.

Gee Steve, not sure that the folks at Garrett would like their Gt 25-30 referred to as cheap generic. Particularly given the close link Garret has to other turbo suppliers...

My post was meant to refer to the pricing and the inclusions of all the fiddly bits you need to properly bolts the things up.

IMHO Garrett 25-30's are a very good thing on an RB26.

Well, we need to get something straight, HKS make GT2530, garrett dont - places like Horsepower in a box seem to be jumping on the HKS bandwagon by naming their turbos the same.

A garret 25-30 is not do the same as a HKS 2530 - PERIOD. The combination of wheels and turbine/compressor housings is ONLY sold by HKS. they started naming them, then others do the same or tell you they can do the same - its just not possible unless they buy the parts from HKS and put them together, which is more expensive than just buying it complete from HKS.

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