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Hey everyone, I just got the call today that my GTR is ready with new garrett 2860r-5's, On the phone he said i gained a bit of midrange power than the previous setup i used to have trust t517z's. Its making the same peak power as before but im just a bit spectical for some reason after that that he has used -7's i figured that i would have no gain in midrange and a better topend. I havent asked him what the top end is like he know's that i like a bigger kick rather than response so i figure if it is making more midrange that the top end will drop off. I know that with -5's the Topend should Definitely should be there and start to pull from higher in the rev range and not lower and die off. Any ideas? i havent asked him when its making full boost yet and if it does pull hard to redline. Thanks for some advice.

Depends on what spec the 517's were in.

You've really provided no info dude... what power it has made, dyno sheet with boost plot etc etc.

Only way to check it the turbo ID tag, good luck getting a look without taking half the car apart

Haha yeh thats what im afraid of mate. Thats why im hoping he doesnt screw me knowing that you know. I have aftermarket induction piping so i can get all that off Pretty easy i didnt think the garrett's came with anything on the ID?. The t517z's where the 8cm Version brand new.

I know that the -5's arnt that good for a standard rb26 my internal's are standard i decided on the -5's because im planning on doing a rebuild later on and using them for what there capable of alot more boost. Right now i think its running 19psi so they should have alot more in them yeh? i will ask the tuner on 19psi they shouldnt run out of puff at 75000rph yeh? im not saying they are i havent seen the dyno sheet yet im picking the car up this afternoon. I guess if it comes on boost early and has a gradual power increase that doesnt hold till redline there not -5's. I have cam's just about ever bolt on mod accept internal's. Just makes me really wonder about gaining in the midrange you know i just dont think it should gain in the midrange if i have big turbos that should have a bit of lag. BTW it made about 400hp on 18psi like the t517z's did at 18psi.?

What - why did you change from T517Zs to GT2860-5s? I was always pretty sure the T517Zs are a slightly larger turbo than the GT2860-5s/GT2530s? Also if you are maxing neither out you're not too likely to see gains, need more info on your setup but I am getting the feeling you just did a side step if not a downgrade in flow potentially and wondering why you didn't get more power.

Mate i changed the turbos because they siezed. ill get the dyno sheet up tonight.

wouldnt it have been easier to get them rebuilt rather than buying 2 new turbos of poorer quality????

i never said they were no good just maybe not as good as the t517

just an opinion.

and dont they have a warranty to die after 4000km i would imagine the supplier would have some sort of warranty...

Also i dont think the -5's are the same as 2530's thats the -7's

*shakes head*

I think you really need to get your turbo part #'s, and specs correct before you go saying you think you dont have what you paid for.

-5's are similar to a HKS 2530

-7's/-9's are similar to HKS GT-SS/R34 N1

There is enough info on the forum stating the above im not sure how its even something that you could get wrong.

Even Garretts website will tell you the HP rating for each.

If the reciept has the part# of -5's on it, then thats what you have. Have you even checked it yet?

Also did you fix the problems that causes the 517's to seize? Because if you didnt, it'll happen with the -5's... turbos done just "seize" for no reason, especially not near new ones.

Yep x2 ^^ Thats exactly what I was going to say on both fronts. The Mitsi/Trust turbos are strong as hell and aren't inclined to just seize - especially both of them!! It would have been cheaper and easier to take them to a turbo expert to look at what caused them to fail and then get that address fixed and the turbos rebuilt.

Depending on the dyno you are using you probably could do with more work to the engine itself as neither turbo combination should be limited to 300kw @ wheels, makes me think the engine itself is the let down.

Edited by Lithium
*shakes head*

I think you really need to get your turbo part #'s, and specs correct before you go saying you think you dont have what you paid for.

-5's are similar to a HKS 2530

-7's/-9's are similar to HKS GT-SS/R34 N1

There is enough info on the forum stating the above im not sure how its even something that you could get wrong.

Even Garretts website will tell you the HP rating for each.

If the reciept has the part# of -5's on it, then thats what you have. Have you even checked it yet?

Also did you fix the problems that causes the 517's to seize? Because if you didnt, it'll happen with the -5's... turbos done just "seize" for no reason, especially not near new ones.

Just for reference for those playing at home(GCG has a run down and a link to the Garret flowcharts)

2530- http://www.gcg.com.au/turbo/ViewProduct.aspx?ProductID=15

GT-SS- http://www.gcg.com.au/turbo/ViewProduct.aspx?ProductID=11

R34 N1- http://www.gcg.com.au/turbo/ViewProduct.aspx?ProductID=16

Lists the differences in HP and the turbo itself, and GCG specify the -7 as R34 N1 with the other two as "upgrades" with the -5 having a higher HP rating.

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