Precision Billet Turbos

[PJ.]

I picked up my 6870 on Saturday. Will be going on a 10:1 4L v8 on e85. Keen to see how it compares to the old t04z!

Liking the sound of this! Hoping you're gonna stuff some boost into it!

[QUP29]

any results?

i should have some results on my pt7275 0.81a/r fairly soon i purchased it before the 6870 came out, i wouldn't mind doing a back to back test against the 6870.

Edited January 31, 2015 by QUP29

[silvianc]

Finally got my car tuned.@19 psi, 93 octane 611/449 tq on precision 6262. Lmk what u guys think

[QUP29]

After some consideration I'm trying to swap my 7275 for 6870. Fingers crossed

Also it's going onto

N1 RB 2.7 JHH Racing built block

Edited February 2, 2015 by QUP29

[Buraz]

I'm currently doing a single turbo conversion on my GTR with a 6262. What have people done with the water lines since these turbos don't need them?? I'm trying to figure out best solution.

[Joshbigt62r]

Just loop it to it self? Idk

[Buraz]

So the one coming from behind the head connected to the one from the front?? I'm a bit lost here not much info out there.

How about the one on the block down the bottom, just block that one off?

[GTRPSI]

Block them off, simple.

If you look at a RB30 series 2 block, its what was done on the non turbo models.

[Buraz]

Okay I guess that's easy enough

[czy18e]

I can't get my head around how a 6870 can make more power than a 7275?

Are they going to make a gen2 71 or 72mm turbo?

[SimonR32]

Mate finally bit the bullet and is ditching his GT3076R for a 5858 on his R34 Gt-t, was making a touch under 500 before so I'm guessing it will bump up to around 550 with not too much more lag

Went in for a tune last night. 525rwhp on 1.4bar and 555hp on 1.6bar before it started having valve spring issues top end. Higher boost looked like it was heading just under 600hp with 1.8bar.

Boost comes on around the same as the 3076R but makes a bit more power earlier (200rpm in lower range when ramping boost) and makes an extra 70-90hp on the same boost through the mid range and top end. Overlay with the T67 on my old green car and they were very similar but the 5858 will smash it with the valve springs sorted and some more boost.

Forgot to get a graph printed (will get one when valve springs are done) but it's probably the best mid size turbo I've seen on a RB25

TLDR; Comes on earlier and makes shit loads more power than a GT3076R

Edited February 19, 2015 by SimonR32

[dr phil]

What exh housing was in use with the 5858? Other specs? Great result...

[methz]

very interested in 5858 now

[MrFijiGold]

Awesome results. I thought the 5858 would be laggier then the 3076 by miles and that the 5558 would be a closer match. Apparently not!

Im guessing .82 rear? BB version?

[SimonR32]

Awesome results. I thought the 5858 would be laggier then the 3076 by miles and that the 5558 would be a closer match. Apparently not!

Im guessing .82 rear? BB version?

Technically boost builds a little slower on the 5858 but I guess it's flowing a bit more air so more power down low. Owner says it feels better low down on the road than the GT3076R as well

Yes and yes to the other questions

Edited February 24, 2015 by SimonR32

[MrFijiGold]

Thanks mate. Interesting indeed!

[SimonR32]

Damo over here just got his 2.8L and 6466 tuned. Don't think they have pushed it too hard up top but the mid range is stonking!

[Hattori Hanzo 69]

As i couldnt find one prior to deciding turbo (simon assisted in decision) read most of this thread to find it.

overlay of RB26 6262 V RB28 6466

[SimonR32]

Will give an idea of response and acceleration from a 6262, 700hp for the first run through gears and then around 600hp when mucking around on track.

[Nismo 3.2ish]

did I notice a little wet spot on the passengers lap,lol

Looks like fun, not much room for error with that power