Precision Billet Turbos

[PJ.]

Yeah those numbers seemed high for a 6766 on a Mustang, though I am still shocked that people are taking hp ratings as some kind of gospel. How much did you make atw on your old GT3076R? And what are GT3076Rs rated at?

The 6870 is certainly looking the goods, no matter how you slice it. Would have loved to have seen FPs Super94/99s on more things - they are in T4 twin scroll and imho until this came along the best thing since sliced bread for the ">6766 power without going BIG frame".

Ha, you stumped me on that one, I'm one of those guys. It was a 3037S, HKS rated to 480PS, Garrett 525hp, I made 503whp. In saying that, we pushed it to 25psi with a T2 1.12a/r housing, it had a held a flat boost curve unlike the .73 which would fall from 24>22psi (458whp). Car full weight went 10.4@136mph 2870lb.

The figure for which I base my decision on turbo selection is what the manufacturer rate them to anyway, as long it is capable of making that then it's all good. Going gung ho and trying be superman by making a shitload more that what they rate them to usually means that you're just reducing the life of the turbo in the first place. Hit your goal with the smallest turbo possible by all means, get greedy and you might find yourself with nothing left on your shaft. Hmm that sounds kind of funny...

In saying that, even with their massive claims, the yanks are doing some damn impressive stuff. I'll be ordering a 6870 in a couple of weeks depending on a call tomorrow. 1100hp at the crank should see my car trap 168mph. I'm feeling a bit excited.

[Ryan1200]

PJ did you mention earlier that the JW automatic GTR ran 8.7 on a 6766? GST or not that is making some serious power from a 67mm

[Lithium]

In saying that, even with their massive claims, the yanks are doing some damn impressive stuff. I'll be ordering a 6870 in a couple of weeks depending on a call tomorrow. 1100hp at the crank should see my car trap 168mph. I'm feeling a bit excited.

Fwiw FP's closest equivalent to the PT6870 has pushed a couple of AWD Mitsis to very low 8s and over 180mph in cars which probably aren't hugely different in weight to your car, 168mph shouldn't be a massive ask from a PT6870 by any stretch

[PJ.]

Ryan, absolutely impressed with that result, as I was with the STM Ricer at 2850lb and 8.75@167mph!! And I'm not having a dig at what the cars have achieved, only how our figures compare to overseas. At the end the day the track is what tells the truth to me.

Lith, totally agree, if I was turbo sponsored, I'd be happy to try and push the 6766 to 167mph (ran 154.86 on 36psi). The 7175 is pretty much tapped on 52psi and it went 164, the only thing I can really do is go out again, with more power and the longer gearing it has now 4.11. I think 170mph is possible, high 170's though? Not gonna happen.

[PJ.]

PJ did you mention earlier that the JW automatic GTR ran 8.7 on a 6766? GST or not that is making some serious power from a 67mm

Just to elaborate on it also man, the car setup has a massive influence over the ET. The car trapped 153mph, that is a very good time for the trap speed.

I don't know of the weight, but it's an RB30/26 auto and it launches like a bat out of hell. Pretty sure when I spoke to Justin they had maxed it out, my 6766 showed signs of boost falling off @ 42psi (850whp) and the 7175 is showing 920whp with nothing left.

If I was a betting man I'd say that I was at the limit of the 6766's 935hp rating and probably sitting on 1000hp at the crank (7175 rated to 985hp).

Only sure way is an engine dyno. Rather wear my engine out on the track.

Edited November 12, 2014 by PJ.

[Lithium]

Lith, totally agree, if I was turbo sponsored, I'd be happy to try and push the 6766 to 167mph (ran 154.86 on 36psi). The 7175 is pretty much tapped on 52psi and it went 164, the only thing I can really do is go out again, with more power and the longer gearing it has now 4.11. I think 170mph is possible, high 170's though? Not gonna happen.

Oops yeah sorry I wasn't saying that you would go near 180mph... I still think those cars are lighter and possibly generally more hard core set up to run those higher traps so not apples and apples, but still pretty amazing stuff compared to what people were doing similar times and traps with not that long ago considering.

[PJ.]

So my 6870 will be on the way shortly, I plan to push it until it has nothing left to offer which according to its 1100hp rating should be a nice gain over the 7175. Certainly won't sound as good or hit as hard but that's not the reason I'm putting it on.

I would expect it to need at least 55psi to get it to a point where it won't offer any more power.

I'm chasing more response and the driveability that the 6766 offered. This is a custom 1.00 divided T4 housing we are using, so it will be a good comparison as the 7175 was running a .98 T4 divided.

It packs the goods to run low 8's in my car, I will try and better my time in the coming few weeks with the 7175 through better car setup before retiring it for turbo # 9 and the 6th Precision turbo since 2010.

[Rbdirty30]

Is the test for the 6766 somewhere in these pages ? I want to see the difference between the .81 and .96 rear housings

[SiR_RB]

Precision just released a t4 divided rear for the new 6870

[eXquiSit]

whose going to be the first to use one of the split rear 6870s and post results?
=)

[Rbdirty30]

I called powertune today and there happy to swap over my 6766 (still in the box new) for a 6870 and I pay there difference between the two, I'll be putting it on a 26/30 but I've got to finish building my motor. I'm going to get the divided .83 rear housing . Just have to wait for the turbo to make its way over to aus pretty sure?

[SiR_RB]

My mate will be running a t4 divided 6870 on a nitto 2.8 stroker

Won't be ready for afew months still

Aiming for 600-650kw

[Rbdirty30]

This might be a dumb question but what is the difference between a ported 's' cover and a ported 'h' cover?

[jangles]

This might be a dumb question but what is the difference between a ported 's' cover and a ported 'h' cover?

2.5" outlet vs 3" outlet

[Rbdirty30]

Cheers jangles

[G37Sam]

Anyone manage to get their hands on a 6870 yet?

[FJ 720]

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!

[Nismo 3.2ish]

What are you hoping to get out of it, rated @ 1100HP, that will be mad

Love to see the Dyno on this against the T04Z

[FJ 720]

At this stage it'll be limited by standard 1uz bottom end (just head studs, mls headgaskets, porting, cams and valve springs) so I won't push it over 400kw. When I get the built bottom end back under it and a trans that can handle the power I'm hoping it will do 600kw.

[Nismo 3.2ish]

At this stage it'll be limited by standard 1uz bottom end (just head studs, mls headgaskets, porting, cams and valve springs) so I won't push it over 400kw. When I get the built bottom end back under it and a trans that can handle the power I'm hoping it will do 600kw.

Yeah everything has to be able to handle it, with the 4Lts that should be fun, when you do the bottom end and turn it up to 600Kw, hold on tight

Put a 6262 CEA on my R34GTR , wanted to get rid of some of the lag from the T78, worked OK but not good enough, so got a 3.2Lt stroker going in and the 6262 should work great with the extra torque and rated around 700hp it will be more than plenty for what I want from the car.