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400 real whp from a VG33ET @ 15psi boost


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Talking about a corrected real SAE power figure with a nice actual 3000rpm torque spread, not 'calculated', real and actual. I actually had one built one with a GTX3582R turbo, engine failed so it was removed and I sued the excuse for a builder and won. But the Z did go on a dyno and while the power was not too bad it was never going to make 400 as it was, with the usual hot off the shelf parts, head job, etc.

 

I'm a bit obsessed with these engines and after consulting a real performance engine builder have a pretty fair idea what it would take to get the required power, which incidentally my stock VG30DET engine exceeds with the same turbo at 15 psi boost. So, to sort the engine men from the boys, tell us what would do it. To make it simple, assume that the exhaust and basic intake systems would do the job if you like.

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I don't know that much about the VG engines. I know there's a lot you can do with one, but they're an older model these days.  I, myself, like the VQ engines. Unboosted the VQs pull in around 300 horses +/- depending on model just stock. That's nothing to complain about.  I've heard of TT applications pushing 500HP on low boost. 

 

There's not really an Ideal way of powering up your car beyond making sure the tune is good. All the quality parts and money won't save an engine that's badly tuned. Just putting it on the Dyno is one thing, but using that dyno as a tool to help properly adjust the fuel tables is the best idea. 

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Well Nissan did manage to make 1200+ hp with them back in their  IMSA GTU/GTO/GTP hayday.  They are getting a bit long in the tooth by today's standards, but they are still plentiful enough, pretty bullet proof, and make gobs of power over a nice wide rpm range.

I'm a bit obsessed with these engines and after consulting a real performance engine builder have a pretty fair idea what it would take to get the required power,

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The VG33ET I had built used a MoTec M600 engine management system, going on the dyno involved a full tune. The engine had 1mm oversize Ferrea valves, big JWT cams and so on so it was maxed out using off the shelf parts, not much point going above 15psi according to the tuner because the power gains there were poor.

 

As I said, I do have a bit of a thing about these engines which does not make any bang for buck sense. At a guess it would probably cost about $6000.00 or so more, using what I already have, to get 400whp.

Edited by 260DET
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Talking about a corrected real SAE power figure with a nice actual 3000rpm torque spread, not 'calculated', real and actual.

 

First, your requirement for SAE power is kind of weird. It's not applicable to turbo cars, you should be using uncorrected to get a more "accurate" reading. Second, if the difference between 'making' your required 400hp is the difference between STD and SAE correction factors, there are other issues.

 

Second: 400hp across 3000 RPM? Not going to happen on the single cam. At least, it's not going to be usable. You'd have to make a peak 600+ HP to have any powerband like that, and that would mean wild cams and a completely unusable lower end.

 

I made 400+ ft-lbs. across 1000 RPMs, and that was at 18psi. With cams you could extend that out 500 RPM, with some headwork maybe 200 more... I just don't see it going to a 3000 wide torque peak. If you want that, get an LS. They can do 400 HP plateaus with intake, headers, cam and a tune.

 

To even approach this you would have to spend enourmous amounts of time and effort on the heads, which is the limiting factor. After 5000 RPM, the VG can't breath very well. At 7000 RPM or higher, you better have a solid valvetrain or you will have problems. So that limits you to what? 4000-6000 RPM to make all that power? Not going to happen.

 

Change your criteria to 1000RPM wide, 400+ HP and I can show you plenty of examples.

Edited by BLOZ UP
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I did say in the opening post over a 3000rpm torque spread BLOZ UP, which incidentally the present VG30DET engine does very nicely. Other than the VG33ET obsession, if the DET was going to be changed it would be for a na LS for sure.

 

Yeh, it's the single cams heads which are the problem, both as to fitting the required inlet valves and cams in. Electramotive et al used NISMO heads so those race engines are not really comparable. But I don't know if the required valves and cams would give the required torque spread even though I'm satisfied that 400whp is possible with those mods. The comment about SAE corrected etc stems from my unpleasant experience a few years ago when horsepower figures were being quoted that I knew damn well were not possible with the mods quoted then.

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I did say in the opening post over a 3000rpm torque spread BLOZ UP, which incidentally the present VG30DET engine does very nicely. Other than the VG33ET obsession, if the DET was going to be changed it would be for a na LS for sure.

 

Yeh, it's the single cams heads which are the problem, both as to fitting the required inlet valves and cams in. Electramotive et al used NISMO heads so those race engines are not really comparable. But I don't know if the required valves and cams would give the required torque spread even though I'm satisfied that 400whp is possible with those mods. The comment about SAE corrected etc stems from my unpleasant experience a few years ago when horsepower figures were being quoted that I knew damn well were not possible with the mods quoted then.

 

Ah, I missed that. The title and the beginning of that opening said power, I must have skimmed over the torque part for the spread.

 

So, it seems a lot more possible now, maybe you could get a 3500-6500 spread of torque. I got a 3500-6000 of 300+ ft-lbs. of torque with just turbo, intercooler, intake and exhaust.

Edited by BLOZ UP
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When we ran the VG33ET (that later stuffed up) on the dyno, we got 300ft-lbs between 3500 and 6200 (maximum 400ft-lb), using the parts already mentioned plus an intercooler, custom intake and 3.5" dump into a 3" muffled exhaust on pump fuel, about 92 octane US standard. Exhaust manifolds were stock. There was nothing more in that engine as it stood, it was tuned to the max but just died at 6300rpm. No valve float we think, it had JWT valve springs.

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Yeah they fall off pretty quick after 5500. You can mitigate it with cams, valves, and such but only so much. Mine was 300+ ft-lbs, 440 max:

 

BLOZUP.jpg

 

That's at 91 octane. 12:1 across the board. Crappy front mount log manifolds. I'd really like to see if my tubular manifolds make a difference, as the rest of my setup in my current 280Z is pretty similar to the old setup that graph is from.

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To complete the wheel power figures, max 357whp @ 5500rpm. I'm satisfied that's about as good as it gets with a VG33ET without much more expensive mods. Used the same tuner and dyno with the stock VG30DET fitted and got 420whp with a very nice wheel spinning 3000rpm torque spread. Same turbo and 3" exhaust, similar 3.5" dump.

 

But in my dream garage I'd still like to have a VG30DET equivalent power VG33ET in the engine bay. Look! old school tin valve covers donk.

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What's required to get 400whp (500 at the flywheel) according to the pro I consulted, considering the head only. Inlet valves 3mm oversize out to 45mm (present oversize Ferrea are 43), cam lift up from present S2 JWT lift of 11.76mm to 12.7mm minimum. Followed by turbo specific head work.

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IMHO 357whp is about as good as can be expected from the head restricted single cammer. Stock VG30ET delivered what, a bit over 200hp at the flywheel? 33 as it stands will do very little better than a 30 due to head restrictions. More than doubling stock power using fairly modest improvements is pretty spectacular I reckon. More than that? Hmmmmm.

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Stock vg30et was rated at 250, in theory another atmosphere should get 250 more.  Given some supporting mods many guys get + 70-80% adding 1 atmosphere in the real world.  This is not universal and I haven't done it on a VG but I've seen it on everything from Datsun l6's (sohc) to small block v8's (ohv) to VW i4 (both 16v and 20v).

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IMHO 357whp is about as good as can be expected from the head restricted single cammer. Stock VG30ET delivered what, a bit over 200hp at the flywheel? 33 as it stands will do very little better than a 30 due to head restrictions. More than doubling stock power using fairly modest improvements is pretty spectacular I reckon. More than that? Hmmmmm.

 

 

I'd have to disagree. Put a proper modern turbo on a VG30E(T) or VG33E and you will see plenty of power. A proper turbo and aftermarket cams and valve springs and you can see a nice improvement to the powerband and plenty of power. 

 

My brothers Z is still on a bone stock bottom end with a 1/4 of a million miles. He's replaced the cams and is running a billet PT6262 turbo, front facing tubular manifolds, NISTUNE and E85. Were expecting a solid 500+WHP and similar torque on high boost...already been for a few pulls and it pulls good   :).

 

IMG_20130803_184127_zpscef4f3e2.jpg

 

SHORT vid i took of a quick 2nd gear pull:

http://www.youtube.com/watch?v=X93SP7586mg&feature=em-upload_owner

 

Edited by RedBeauty84ZX
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OK lets look at a couple of modern multi valve highly developed turbo engines in high performance cars. The GTR with a 3.8 liter engine manages around 540 hp while the Porsche 3.6 liter 997 does around 520hp. Knock off say 20 percent for driveline etc losses on a wheel dyno and we have 436 and 416 hp ATW. So the claim is that the single cam two valve VG engine with a lot less displacement and OE heads will do better than the Nissan and Porsche efforts?

 

C'mon, get real.

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