Precision Billet Turbos

[zebra]

Cheers

How does the .68 T4 compare size wise to a GT30 .63?

3" outlet?

Sorry for all the questions lol just trying to figure out whether I should lump it with a custom manifold for a td06, use my TD07 or sell it and get one of these.

Plus im a bit of a geek when it comes to this stuff lol

[Rolls]

LOL only just noticed the intake temp, went to post and you had already posted...

So dodgy temp correction and boost wound up so high the dyno can't even read, INTERESTING

this is a stupidly high ramp rate to smooth it out lol, don't doubt the power, just how smooth it is lol

[juggernaut1]

It's not real, you have just hit the map sensor limit of a DD dyno!

Look at this for reference of the same thing happening...

and another example

http://www.xtremefordtuning.com.au//images...0F6%20Boost.jpg

[Ryan1200]

I attempted to enter a negative figure into a DD Dyno to check correction factor but it didnt except it. I tried IT of 1 dergree C, 12.5 and also tried unplugging the temp sensor and got the following corrections. Wishful thinking but imagine if the dyno was removing another 10% from the figure...

[juggernaut1]

I attempted to enter a negative figure into a DD Dyno to check correction factor but it didnt except it. I tried IT of 1 dergree C, 12.5 and also tried unplugging the temp sensor and got the following corrections. Wishful thinking but imagine if the dyno was removing another 10% from the figure...

Thats generally been my understanding - the greater the intake temp exceeds the ambient temp the greater the correction (inflates power) and vica versa (deflates power). So there is no correction where intake temp and ambient temp are the same.

[Ryan1200]

25 IT 25 AT.

[juggernaut1]

Just as I thought...thanks for that.

Edited October 15, 2010 by juggernaut1

[DVS JEZ]

After looking at the graph this morning, Chea though there was a bit more in it

Starting to lift the head at that power so we're gonna have to leave it there for now. Have the Motive drag challenge next week, after that put a Tomei head gasket on and a 6262SP!!

I'll start making the vid

awesome results PJ well done,

but

Look how the power drops up top....

Quick everyone should start hating precision turbo's like you hate Hypergears...

[zebra]

Its not hating hypergears its simply pointing out they have a 1500-2000rpm power band.

The interseting thing would be to see what boost the motor actually saw...any engine ECU datalogs?

[juggernaut1]

Quick everyone should start hating precision turbo's like you hate Hypergears...

But the boost curve of a Precision Turbo is rock solid table flat .

[PJ.]

This engine doesn't have valve springs, don't think they'd be loving life right now. It would be to interesting to see if the power would hold flat then (some studs and a head gasket would help us too)

We'll log it @ the track for you Can't wait it should see close to 135mph trap speed!

[Powertune Australia]

Well we've since replaced the head gasket in the S14, and while it was apart installed ARP head studs and a BC valve spring and a retainer kit, which has allowed us to rev the engine a bit harder.

The result was 392.3kW at the wheels with a 35psi spike which fell down to a stable 33psi.

For the guys who were sceptical before, we ran it at 29psi and got 367kW at the wheels. So there it is, the limit found of a 5557. Pretty crazy stuff really from a baby .63 exhaust housing!

If the weather is good tomorrow we'll be taking the car to WSID on full slicks

Here are the sheets

And now for the Skyline lovers, here are some pics of the R34 that we're building, you can check out a full spec list on our site at: http://www.powertune.com.au/projectcars-gtr.html

It now features a BC 2.8 and Precision GT4271R ball bearing billet turbo, Powertune twin scroll manifold, hopefully we'll have it run in and tuned by the end of the month, then of course straight to the drags

[N1GTR]

Whats the target for that one?

[Powertune Australia]

So far every Precision turbo we've seen has gone beyond its power rating comfortably, if we can do the same with this one is will be a genuine 1000hp car, so I guess that will be our aim

[SimonR32]

For the guys who were sceptical before, we ran it at 29psi and got 367kW at the wheels. So there it is, the limit found of a 5557. Pretty crazy stuff really from a baby .63 exhaust housing!

Was not skeptical before... Was just noting that you had used more boost than you were claiming!

I myself am super impressed with your results, so much so that if you get your ass into gear and test a 5557 0.63 on a RB25 I would be very interested in purchasing as I'm just about to do a 25 conversion on my 32 this month and looking at a few options for turbos at the moment

Edited November 2, 2010 by SimonR32

[XRATED]

Bit of an update for my rb25+5557 combo...

Picked it up last week (arrived in aus the day before) semi tuned.... still having dramas! Electrical/ignition, burnt the clutch the first night, no vct still, only 18psi atm on a verrrry conservative tune.

Feels good to drive with off boost, it starts making good power from 3k onwards.

I'm glad powertune has pushed this turbo to it's limmits... I wasn't going to push 30+ psi into my stock rb25. I'll see where we go at 250-260 odd on 98.

Cheers

Justin

[Powertune Australia]

Was not skeptical before... Was just noting that you had used more boost than you were claiming!

I myself am super impressed with your results, so much so that if you get your ass into gear and test a 5557 0.63 on a RB25 I would be very interested in purchasing as I'm just about to do a 25 conversion on my 32 this month and looking at a few options for turbos at the moment

Yes the results are awesome, this time we turned it back to show that we were telling the truth about the boost though, as I can't show you the log on the Haltech... well I could but it's too much mucking around for a busy workshop.

As mentioned previously, we will offer free tuning to a donor RB25DET owner wanting to put one on a 5557 purchased from us. Don't be shy guys If we had an RB25 as one of our project cars it would be on it!

The turbo's and all other info can be found on our website.

And the 6262SP will be going on the S14 next after we race it, 40psi here we come. Wonder how/if the standard bottom end will let go!!

[Lithium]

Is that 392kw on fully stock bottom end??

[Powertune Australia]

Sure is, Lith

[Rolls]

How long do you think that will last?