Precision Billet Turbos

[HarrisRacing]

The 6466 see's over 600kw under 30psi on 2.6 and strokers.

A stroker means less rpm more than anything

As for blocks need grout etc. Many cars over 1000hp don't and haven't

sorry to keep steering this away from turbos, but BC (and myself as a mechanical engineer) feel that a billet chromoly crankshaft is considerably stronger than stock based on materials selection alone. The marginal increase in stroke (73.7mm stock to 79mm BC) therefore does NOT reduce overall usable powerband on the RB26 (ie I will not have to LOWER the rev limiter over stock when using this crankshaft). This is one reason you don't lose RPM with a GOOD stroker crankshaft in these engines. I think I will see how the car acts on the dyno and will likely still be keeping mine at the 8250 factory redline, but after talking to BC (prior to ordering mine) I'm pretty sure I recall discussing a figure in the 9k-9,500 on the crank with an insane HP rating...and I went with the lower duty "sportsman" rods...because I wasn't going to make more than 200HP per rod. The only difference between their sportsman and +625 rods is the fasteners. Rods are exactly the same.

[jangles]

sorry to keep steering this away from turbos, but BC (and myself as a mechanical engineer) feel that a billet chromoly crankshaft is considerably stronger than stock based on materials selection alone. The marginal increase in stroke (73.7mm stock to 79mm BC) therefore does NOT reduce overall usable powerband on the RB26 (ie I will not have to LOWER the rev limiter over stock when using this crankshaft). This is one reason you don't lose RPM with a GOOD stroker crankshaft in these engines. I think I will see how the car acts on the dyno and will likely still be keeping mine at the 8250 factory redline, but after talking to BC (prior to ordering mine) I'm pretty sure I recall discussing a figure in the 9k-9,500 on the crank with an insane HP rating...and I went with the lower duty "sportsman" rods...because I wasn't going to make more than 200HP per rod. The only difference between their sportsman and +625 rods is the fasteners. Rods are exactly the same.

Requires less rpm to make same power with any given same turbo.

Stock cranks will go to 10k no worries

[HarrisRacing]

Requires less rpm to make same power with any given same turbo.

Stock cranks will go to 10k no worries

Oh there are always worries at 10k rpms of boosted rotating mass at your heels!

But yes, everything I have picked for my setup is to keep the rpms lower and powerband more responsive. Cams, turbo, stroker, etc. I honestly think my bottom end will handle anything this turbo can give it. I have calculated that the 8374 EFR on my 2.75L stroker will start dropping boost sustainability (only 22 psi) at 8,500 rpms (max air flow of 79 lbs/min) but will be dropping power earlier at 7,500 rpms. Maybe I'll set the boost drop threshold as redline, but after seeing videos of how well the RB28 in the Z-tune responds (and from what it looks like an 8250 rpm limit), I'm thinking I'll be right there with their response level which will be fine with me.

And thank you for your input...it is appreciated. I don't want to sound like a know-it-all. After pulling an engine that suffered such massive rod bearing failure from my car, I'm thinking lower rpms and more displacement is what I wanted to go for - IE reliability. Of course I do not know the circumstances under which this engine failed as I purchased it with a rod knock.

Edited July 7, 2015 by HarrisRacing

[QUP29]

Requires less rpm to make same power with any given same turbo.

Stock cranks will go to 10k no worries

it's not just the crank that will let you rev, need good head. Also dual valve spring will help to make it safe to rev. Edited July 7, 2015 by QUP29

[QUP29]

I made just shy of 500kw at 6300 rim with a 6466 while still tuning top end. That block died a painful death, along with my wallet. The 6466 at 35+ pound should see 600+ on a well built stroker with a good head. I love good head.

like this guy says... Expensive lesson, I'm not risking it as its taken me over 1yr already!

[jangles]

it's not just the crank that will let you rev, need good head. Also dual valve spring will help to make it safe to rev.

There was never any mention of head components, just capacity.

[Hattori Hanzo 69]

doing 740hp/550kw with a 7,250rpm rev limit HKS 2.8 with a 6466

[jangles]

RB30, 6466, 23psi

With the 235/40R17 195km/h is ~6850rpm, 115 is ~4000

[GTRNUR]

I like the look of that graph. It basically proves my goal of 24lb +E85 will produce 550kw on a soft tune with my 6466.

On the stroker/rev topic. The full counterweight 90mm crank engine I have now feels way smoother than the modified 87mm stroke RB30 crank I ran in the previous engine.

The limit for most motors these days is what rod bolts are used. Piston metallurgy/forging and designs are being proven to 11,000 rpm on short stroke engine, however you need to look at the piston acceleration rates from TDC of an RB26 vs RB3X engines to see the difference on engine stresses. From memory, 8000 in my motor is close to 10000 in a 2.6. Longer rod engines have more mass swinging around too, which puts more loads on the rod bearing and bolts at higher RPM. (Correction) Less of a factor for the 2.9lt and less crowd though.

Beyond revs though is when your cylinder pressures start causing issues like lifting the head (stretching head studs), grinding rod bearing/journal contact due to compression of the lubricating oil film, and pushing the journals out of round for the really insane power levels. When you think about it, it is these last few things that make the 2J the stronger performer as the big power engine typically run 1/2" 625 head studs and the bottom ends are like a diesel engine.

Edited July 7, 2015 by GTRNUR

[jangles]

I like the look of that graph. It basically proves my goal of 24lb +E85 will produce 550kw on a soft tune with my 6466.

On the stroker/rev topic. The full counterweight 90mm crank engine I have now feels way smoother than the modified 87mm stroke RB30 crank I ran in the previous engine.

The limit for most motors these days is what rod bolts are used. Piston metallurgy/forging and designs are being proven to 11,000 rpm on short stroke engine, however you need to look at the piston acceleration rates from TDC of an RB26 vs RB3X engines to see the difference on engine stresses. From memory, 8000 in my motor is close to 10000 in a 2.6. Longer rod engines have more mass swinging around too, which puts more loads on the rod bearing and bolts at higher RPM. (Correction) Less of a factor for the 2.9lt and less crowd though.

Beyond revs though is when your cylinder pressures start causing issues like lifting the head (stretching head studs), grinding rod bearing/journal contact due to compression of the lubricating oil film, and pushing the journals out of round for the really insane power levels. When you think about it, it is these last few things that make the 2J the stronger performer as the big power engine typically run 1/2" 625 head studs and the bottom ends are like a diesel engine.

Your setup will be next level again to mine

[GTRPSI]

A balanced stock crank will take far more than what most believe.

RIPs is turning standard factory RB30 cranks to over 10,000RPM and holding well over 1200+Hp reliably.

Similar reports with factory RB26 cranks.

The biggest limitation when using aftermarket forged rods and pistons is the rod bolts and pins used, from there the distortion of the bores is a major player, thats why people use part grout fills, most block cracking between cylinders 3 and 4 is from the front diff forces on launch going through the block.

How many have seen a RB crank that was crack tested actually snap?

And if so was it the crank material strength itself that caused it? Think about it......

[SimonR32]

A balanced stock crank will take far more than what most believe.

RIPs is turning standard factory RB30 cranks to over 10,000RPM and holding well over 1200+Hp reliably.

Similar reports with factory RB26 cranks.

The biggest limitation when using aftermarket forged rods and pistons is the rod bolts and pins used, from there the distortion of the bores is a major player, thats why people use part grout fills, most block cracking between cylinders 3 and 4 is from the front diff forces on launch going through the block.

How many have seen a RB crank that was crack tested actually snap?

And if so was it the crank material strength itself that caused it? Think about it......

The front diff theory interests me, has anyone got proof or is it just a theory? Also does it apply to launches or cornering? Stock or aftermarket diffs...

I've seen a few RB30's cranks snap so they are not infallible, I know RB26 cranks are often unusable second hand because they are bent as well

[iruvyouskyrine]

In what application where the 30 cranks snapped? I know of 2 snapping in big powered 26/30 drift cars in NZ. As far as I am aware at least one of them was an untouched NA bottom end.

[iruvyouskyrine]

[ohno1]

Opinions on a 6466 w/ .84 TS on a built 2.6 with 272/272 10.2mm lift cams?

I have poured through this thread, and as such was leaning towards the 6262 or even considered the 6062 Gen2 thats just been released - but my engine builder is telling me the 6466 is 100% the go

I trust the workshop, but just want to double check other's results; dont want something that comes on at 5k or later.. id rather it come on hard at 4.2-4.5k rpm

Its concerning seeing people say a 6466 outflows a T51R

Edited July 9, 2015 by ohno1

[Blackkers]

with 272 cams and a 6466 on a 2.6L i'd be surprised if it comes on before 5k RPM but I have nothing really to base that on. Hopefully someone can weigh in.

edit: it would be and absolute weapon on boost though

Edited July 9, 2015 by Blackkers

[HarrisRacing]

Opinions on a 6466 w/ .84 TS on a built 2.6 with 272/272 10.2mm lift cams?

I have poured through this thread, and as such was leaning towards the 6262 or even considered the 6062 Gen2 thats just been released - but my engine builder is telling me the 6466 is 100% the go

I trust the workshop, but just want to double check other's results; dont want something that comes on at 5k or later.. id rather it come on hard at 4.2-4.5k rpm

Its concerning seeing people say a 6466 outflows a T51R

Depends on the engine build, max RPM, fuel used, and purpose of the car - but I would look into the 6062 Gen2 for a street 2.6L. Rated at 750HP, the 6262 is 705HP [edited], 6266 is 800HP, and the 6466 is 900HP. I wish precision published compressor maps...It would make it easier to help pick a turbo that matches your goals.

FYI I went with BW 8374 EFR and divided internal wastegated .92 housing and I'm on a stroker 2.75L with milder cams for a better powerband for the street. I'll have dyno information soon, but if you search some of my threads I posted some 2.6L vs. 2.75L stroker match-bot (BW's turbo selection software) potential power graphs to show what the turbos do differently on these engines. If only we could compare them to the precisions.

http://www.precisionturbo.net/Street-and-Race/ss/600-800HP/details/Street-and-Race-Turbocharger---GEN2-PT6062-CEA%C2%AE/582

Edited July 9, 2015 by HarrisRacing

[JH32]

I would look into the 6062 Gen2 for a street 2.6L. Rated at 750HP, the 6262 is 800HP, and the 6466 is 900HP.

Interestingly the 6262 is actually rated at a lower power figure than the 6062: http://www.precisionturbo.net/Street-and-Race/ss/600-800HP/2

[HarrisRacing]

Interestingly the 6262 is actually rated at a lower power figure than the 6062: http://www.precisionturbo.net/Street-and-Race/ss/600-800HP/2

My apologies. You are correct about the 6262. Gen 2 added a lot of power. I edited my response. Thanks.

Edited July 9, 2015 by HarrisRacing

[QUP29]

Opinions on a 6466 w/ .84 TS on a built 2.6 with 272/272 10.2mm lift cams?

I have poured through this thread, and as such was leaning towards the 6262 or even considered the 6062 Gen2 thats just been released - but my engine builder is telling me the 6466 is 100% the go

I trust the workshop, but just want to double check other's results; dont want something that comes on at 5k or later.. id rather it come on hard at 4.2-4.5k rpm

Its concerning seeing people say a 6466 outflows a T51R

6266 would be my choice.