Whats your opinion about the GT3540

[ATMO_BT1]

300rwkw is 400rwhp and in a 1200kg car that should trap 133mph Plenty fast

For 250rwkw, you can either HF stockers, push the stockers till they break, gt3071R will do that with similar response to stock, gt3076 HG TR44, KKR 480 at around 16psi. (latter 2 being less responsive)

Or HG TR43 HF or KKR 430 are similar but cheaper versions of the gt3071.

I was after 300rwkw initially and went for tr44. It made 236rwkw@15psi and I ran 12.1@118mph at similar weight to your car. With a better 60 foot, that power is good for 11.3's. That is "only" 236rwkw so don't get caught up with dyno numbers too much

133mph is enough for a very low 10 depending on gearbox, so i'd say that's perfect for a streeter

I agree the HG TR44 or KKR 480 would do the job for 250rwkw although i would hardly call them "similar yet cheaper versions of the GT3071". The Hypergears and KKR turbo examples are both journal bearing and neither have the same wheel combination as the GT3071r (i don't think!, from memory the 430 is a bit bigger out the back and the HyperGear turbo is much bigger all around?). HP wise they may be "rated" at a similar amount although i believe the usefullness of such "HP" ratings for the sake of comparisons to be drawn accross different companies is limited.
In my opinion they are excellent turbos for somebody on a budget (ie cannot afford a GT series turbocharger and wastegate to match).

[The Real Roadrunner]

The difference in lag will be very minimal as the housings are exactly the same so volume wise the turbo is ingesting the same amount of air from the rear, it just spins in a more aggressive manner with the 35/40 due to wheel design and inducer/exducer size.

there is a BIG difference in the way a 3076r and a 3582r will respond on a 1j.

if its a daily well mannered car or a circuit car your after go for a 3076r with a .82 and with the right driver could get you a high ten anyway (gas may be needed but only a 50shot)

if you want to go quicker and mainly plan on drag racing the a 3582r with an .82 or 1.06 would be the weapon of choice.

if it was a 2j then i would just head for a 3540r as they have an extra 500cc to lug you along off boost.


there is NO common part as far as housings and wheels go between the GT35r and GT30r series of garrett turbos.

cheers
linden

[Smokey228]

300rwkw is 400rwhp and in a 1200kg car that should trap 133mph Plenty fast

For 250rwkw, you can either HF stockers, push the stockers till they break, gt3071R will do that with similar response to stock, gt3076 HG TR44, KKR 480 at around 16psi. (latter 2 being less responsive)

Or HG TR43 HF or KKR 430 are similar but cheaper versions of the gt3071.

I was after 300rwkw initially and went for tr44. It made 236rwkw@15psi and I ran 12.1@118mph at similar weight to your car. With a better 60 foot, that power is good for 11.3's. That is "only" 236rwkw so don't get caught up with dyno numbers too much

See i saw this as an option, but i am trying to build a somewhat reliable 250rwkw...
I know about happy dynos, and im happy to see this number on a happy dyno, provided it makes me smile when i drive it and maybe my pants a lil tight would be nice.. But not damp, thats going to far for me!

Reason im looking at gt3540 now is, put simply, im buying it off jack(atmo)... lol
So if i was going single without this fact, i would still, for comforts sake, end up with a GT30 or 35...

Cheers,
Jase

[ATMO_BT1]

there is NO common part as far as housings and wheels go between the GT35r and GT30r series of garrett turbos.

cheers
linden

Common parts between GT3040 and GT3540:

-Front housing (seen)
-Compressor wheel (seen)
-Rear housing (seen)
-Shaft (have heard)

I have owned and dissasembled both this week and with the examples i saw, the only difference was the rear wheel.

I was under the impression that the 3076r was the same as the 3040r (i thought the 3040r just denoted it was an earlier-production model before Garrett changed it's naming structure to accomodate an expanding range of products) but if you are saying the 3076r shares no parts with the 3540r then it must not be, as the 3040r and 3540r are VERY similar i saw it with my own eyes!

I was at GCG last week with the dissasembled GT3540 and they even agreed, they then said the 3540 would give a real-world gain of roughly 10-15rwhp on the same boost as the 3040.

I feel the confusion here has come from people like myself confusing the 3040 with the 3071r and 3076r.

And Jason, dude, i'll give you the turbo haha you don't have to pay for it!! You make me sound like a dodgey salesman when you say that


Edit:

Here i will add from Garrett's website, the breakdown for the naming of GT series turbochargers:

A Guide To Garrett’s "GT" Model Numbers

GTxxyyzz:

Positions "xx" refers to the frame size of the turbine wheel inducer.
For example the "GT28" in "GT2860RS" refers to its turbine wheel frame size family. All GT28 units use a turbine wheel with 53.85mm inducer diameter
As a rule of thumb, the larger the number, the larger the turbine wheel.

Positions "yy" designate the compressor wheel exducer (major) diameter in millimeters
The "60" in the GT2860RS example above has a 60mm compressor wheel exducer diameter.
Note: Wheel sizes 100mm and over omit the "1" (hundreds digit)
Example: the 02 in a GT4202 refers to its 102mm compressor wheel exducer diameter

Positions "zz" may be used to designate special features of a particular turbocharger where applicable
Example: GT2860RS
"R" = this is a Ball Bearing unit
"S" = used for units which require some differentiation from units in the same family
Compare a GT2860R to a GT2860RS. While both are ball bearing and externally similar, the GT2860RS is better suited for higher-flow applications than the GT2860R. In this case, the S reflects the higher-flowing nature of the GT2860RS

In this school of thought, doesn't that confirm that the GT3040 and 3540 both share a compressor wheel exducer (no word on inducer, but the wheel is still the same size) however feature different turbine wheel exducers? Perhaps even the same rear wheel size considering they are both offered with the same exhaust housing options (.63, .82 and 1.06), these housings are interchangable so i can't imagine why the exducer would be different either.

EDIT 2: However, i can't see how conclusive the above ruling may be with respect to GT3040rs and 3540rs, as obviously neither have a 40mm compressor exducer..

Can one of you more repped up, more knowledged up people clear it up for me??

[Smokey228]

Haha, no man, im going to pay you for it! lol, but what i mean is i wanna make sure the 35/40 is the best for my application...

Otherwise ill let you sell it on calaisturbo and ill just go the gt30 track...

But what ill probably do, is buy it off you, and try it out... If they are as similar as you say and i decide its to laggy, than it shouldnt be a trouble to sell it off and buy a gt30. I assume they both share the same style and size exhaust and compressor flanges. Inlets and outlets?

Cheers,
Jase

p.s. This has been a good day for me. Im at work, and i learnt lots about turbos! lol

[chris davey]

I don't use the terms 3040 or 3540 as they are too ambigous for me. Stating 3082 with .8 turbine a/r leaves no room for error from my way of thinking.

BTW I don't know the stats for 3071 but HG tr44 and kkr 480 are very close to a 3076. same comp wheel and housing. turbine wheel is bigger though resulting in the smaller .63 or .58 turbine a/r.

I think the Koreans thought it was a better idea to copy a good working turbo and take out the BB centre than try and re-invent the wheel (pun intended )

Having not worked on either the 3082 or 3582, why would the compressor wheel be any different? Same 56 trim 82mm exducer, 61mm inducer I thought. And if the comp housing is the same then it basically comes down to exhaust housing, wheel and a/r differences only. Hmm...

BTW if you need to get rid of it, I know a little yellow Rona that could do with it

[ATMO_BT1]

Having not worked on either the 3082 or 3582, why would the compressor wheel be any different? Same 56 trim 82mm exducer, 61mm inducer I thought. And if the comp housing is the same then it basically comes down to exhaust housing, wheel and a/r differences only

This is what i have been trying to word (although not very well ). Assuming that the GT3040 i had (sold today) is really a 3082r for the sake of accuate naming purposes and that the "GT3540" i now have can be titled as an 3582r, then the only difference between should be the rear wheel (denoted by the 30 and 35 in the names of the turbos respectively!). This theory is completely supported by what i experienced this week when comparing the two turbos in the flesh!

[1JZ.747]

in your average 1550 kilo plus car with 1jz come out in i dont feel they would be capable of a ten second pass at that wieght without a fair amount of gas with a 3040.

hell i had a T04r originally which is slightly bigger than a 35/40 from memory and the best we got out of it was a 10.70 at 128mph with a 1.57 sixty foot. great combo that i miss it.

for sure in a light weight car like a celica with a trans brake or a manual on slicks you would easily hit a 10 which matts hypo77 is plain proof of 10.43 at 133 mph, but matt could change gears pretty well.

[The Real Roadrunner]

ok now we are sort of getting somewhere.

the 3082r (that they no longer make) does share the same comp wheel and cover as the 3582r depending on spec/trim
but the rear wheel is different and so is the housing(different internal machining)

the 3076r runs completly different everything bar maybe the core and bearings

if you use the new garrett terminology it makes life a shitload easier.

any specific Qs feel free to ask as ive been working with them for a while.

cheers
linden

[ATMO_BT1]

Specific GT3582r related question :

At what potential level of oil pressure do you feel that the fitment of a restrictor in the oil feed is neccesary?

[1JZ.747]

Specific GT3582r related question :

At what potential level of oil pressure do you feel that the fitment of a restrictor in the oil feed is neccesary?

now thats another interesting topic, i have never fitted a restricter to a turbo oil feed. we run aroudn 100psi in my current engine with no dramas, the last one ran about 80 psi in the stock 1j never had an issue with a turbo.

yet the guy i sold my gt51r too just rooted it at 120psi of oil pressure. and GCG said dotn run over 60 psi.

any thoughts linden

[The Real Roadrunner]

well its actually an arguement ive had many times bcoz i dont believe a restrictor is needed. i do hower run a filter in the feed line of all the garret rollers that i fit.

my reasons are
1. how much oil can go through the 1.6mm hole in the top of the core?

2. how quickly can that same hole clog up with small bits of metal if the normal oil filter doesn't stop it.

i just had a look at the 45r on the shelf and it has a 2.5mm hole so anything bigger than a 35r may require some form of restriction but only in the form of pressure not flow.

ive asked gcg why they only recommend 60psi but they couldnt give me a real reason it was more like "just because"

i asked fred at turbologic and according to him if the bearings shit themselves its due to lack of lubrication but if the seals shit themselves then its normally due to not having a good enough oil drain on there.

there was never a mention of a max pressure just make sure the feed and drain are well thought out.

the filters i use are for -4 braid and are "FLOW EASY", different micron elements are available for them and when you weigh up the cost to set one up V a recore on a late model roller then it becomes obvious there worthwhile.

cheers
linden

[ATMO_BT1]

How much do these filters cost? I recently killed an otherwise new GT3040 because the restrictor blocked with metal (thus giving me the opportunity to go for the 35).

Do i have to cut my braid and purchase two new fittings with which to insert the filter somewhere along the line? Or can the filter simply attach to the oil feed fitting at the top of the turbo's core and the line run into it from there?

[The Real Roadrunner]

i normally put them inline and mount them on the strut tower or chassis rail but i cant see itcausing harm by floating midair.

about $100 for the filter then another $50-100 odd for the fittings but how much did the CHRA just cost you? its less than a 1/4 of the price of the core and youll at least be satisfied knowing that it is there if something goes wrong with your BE bearings.

cheers
linden

[ATMO_BT1]

i normally put them inline and mount them on the strut tower or chassis rail but i cant see itcausing harm by floating midair.

about $100 for the filter then another $50-100 odd for the fittings but how much did the CHRA just cost you? its less than a 1/4 of the price of the core and youll at least be satisfied knowing that it is there if something goes wrong with your BE bearings.

cheers
linden

I didn't replace the CHRA i went out and picked up an entire new (3582r) turbo and gave the 3082r away with the rooted bearings to someone who will have it rebuilt, i think GCG quoted $800 from memory... either way you're right $150-200 odd for a filtration system that acts as a little bit of insurance is a bargain. I just had my fitting guy around then and he hadn't ever used the filters so couldn't really comment on them.

I'm not worried about the big end bearings specifically moreso about the top end as more is standard up there and any sort of fouling would lead to the oil becoming metallic pretty quickly. The fitting guy said that there is a restrictor built into the bolt that runs from the block.. could this be right?