VQ37HR block limitations?
 

Hey guys,

Well after checking out some of the TT threads I was wondering if anyone knows the limitations of the stock VQ37HR block? From what i've seen up to 12psi has been run on at least one so far. Its really too bad that its an open deck block :( That said considering that 12psi TT set up I saw put out around the 500rwhp mark I guess its no limitation for most people. So standard internals and block seem to be alright for 12psi+ and 500rwhp though I imagine a safer number would be around the 450rwhp mark.

Has anyone got water injection set up on their VQ37 yet? FI + 11.0:1 CR and water injection would work quite nicely for a bit of safety margin.

EDIT: I just found some pictures of the stock block that I had on my computer, it looks pretty good even though its a open deck design. A guy I know is currently building a high CR turbo engine so it will be interesting to see how it does, he is using a closed deck v8 with 11.5:1 CR and hoping for 12-14.7psi though he hasn't mentioned if he has chosen single or twin yet.

David

Size of turbo matters more than lbs of boost.

I knew someone would mention that haha :P I guess it would be better to ask what kind of combustion pressure can the stock block handle. I haven't really had much experience with open deck blocks but closed deck seem more than happy to pack in quite a lot of air without any issue any idea what the limits of the VQ37 are?

It's all in the tuning. Plan to go all out when I turbo my car inlcuding an wideband and likely a standalone.

Well from what the vendors have been saying, it's not a good idea to go beyond 550whp. Although they have taken it past 600whp just fine.

mrmixitup by all out do you mean just a stand alone ecu and wideband etc or do you mean a full bottom end build? If the bottom end build will you be keeping the 11.0:1 CR? Honestly from what i've seen if you can tune the factory ECU its better as you can retain factory features and past Nissan ECU's have been very easily tuned so I guess we will just have to see what comes out to tune it with. I'm sure NisRom or whatever will have a set up for the VQ37HR soon enough. Stand alone starts to get ahead when it comes to additional sensors or extra maps etc as most factory ECU's haven't been designed to expand on what they come with stock. I can't see any reason why the factory ECU wouldn't be fine for most builds not to mention save you the $2k for a good stand alone unit. I know older nissan ECU's can be made to work with a wideband so I would assume it should be possible with the VQ37HR as well.

Based on the internals from previous Nissan engines I would say 500rwhp would be about the safe maximum which is still pretty impressive, it means that 95% of people will be able to get their goals on the stock block.

I wonder what results will be had once people start fooling around with the VVEL on the intake cams, its a shame they didn't bother to put any valve control system on the exhaust side, I can see reason for it but I guess the cost/benifit wasn't in it by Nissans thinking or penny counting.

The safe maximum is 550whp as per GTM and some vendors.

400hp N/A on a stock block seems very, very possible, lol. People are hitting 340-350whp with just I/H/E and a tune...CAn't wait for some more mods to come in and take it to that 400hp mark. ^_^

I am quite impressed with the easy N/A performance out of them so far. Once a bit more time is spent on them I don't doubt 400whp N/A will be possible without going to extreme lengths.

Has anyone started working on the VVEL yet? Seems like once people can tune the VVEL there is an easy 5-10% more power on top of the basic mods.

Some of the sponsors/vendors on this site, not to vilify them, don't give a sh&t if you get a TT set up from them, and shortly thereafter you blow the motor despite them tuning it to "safe" levels of boost. They're here to make money.

They say 500hp is "safe." These vendors are gonna tell you anything you wanna hear. I honestly don't think 500hp streetable is realistic, more like 400hp. C'mon, a VQ motor is a corporate motor in a truck, passenger car, minivan and whatever Nissan makes. On the other hand, a Ferrari motor is engineered to take 12:1 compression ratio, use certain alloys for its block, etc. to get their motors to pump out 500hp all motor, they're high-performance motors per se whereas VQ's aren't.

But the caveat is that you know that building your motor aftermarket is risky despite anything vendors say is "safe."

I think that is a good point that you can't trust vendors to give the most accurate information. From all the pictures i've seen the VQ37 is quite a bit beefier than the VQ35 which seemed to be good to around 400-450hp before breaking stuff. If you just bought a brand new G37/370z are you really going to risk loosing an engine over 50hp or take it a bit easier and be safe.

FYI the VQ30DET is good for 500rwhp standard but that was an engine engineered for forced induction from factory. As there isn't much actual experience with the VQ37 yet I'd assume the safe limit is in the 400-500whp range.

Whoa 400Whp is not what I said, lol. 400 at the crank. 400 to the wheels though? Maaannnnnn...That's crazy. That's V8 territory.

Not exactly the vendors. It's the company that makes the kit themselves. GTM has said that 550whp is just where you want to be safe with this block.

I don't know why I said vendors. Pardon the stupidity.

**** if it were me, I'd do full bolt-ons, tune, and a 100shot.

i am very ignorant when it comes to tuning and so forth, but from a 330hp @ crank to 400 @ wheel without FI sounds like a joke to me. could you entertain me a bit and explain how anyone could reach 400 @ wheel without FI?

For the lack of better things to do I have been following M3's FI section on m3post.com. the engine puts over 350 hp at the wheel (414 at crank) and everyone finds it a stretch to even reach 400 hp without FI on that car...

edumacation, please!

Well I cleared myself up earlier. I meant 400 to the crank, not to the wheel.

People are hitting 340-350 whp (if drivetrain loss is %15 it's about 391-403 to the crank) with just I/H/E and a tune. Stock intake manifold, stock throttle bodies, a few other stock things that MIGHT bump the power to 400 CRANK hp or get very close. At least I would think so.

It comes with 336 hp and the intakes and exhausts on the 370 are extremely restricted. This VQ is different from all of the other ones. It's bigger. Comes with a bottom end that, according to paper, lol, can handle 1000whp. Has a different type of valve control unlike what I've ever seen in a vehicle.

But here's the specifics on the motor and where that 1000whp claim came from. http://www.370 z.com/MagazineArticles/tabid/57/articleType/ArticleView/articleId/14/370Z-Engine-VQ37VHR.aspx (take out the space after "370")

Crank HP doesn't really mean **** in the end though. Power under the curve > *

Luckily, no VQ37VHR block has failed yet from boost (that I've known of) so one can't really tell yet the actual limit. But again, there are short term & long term stresses which can cause failures to the block. Yes, crank up the boost on the dyno to even say 700whp your block might not go airborne, but take a 500whp tune and live on the track for sometime and you will kiss it goodbye. GTM said you should be safe with a stage 1 on a stock block (500whp almost) but only time can verify that.

Funny how a TT'd 350Z (in Dubai) brags about pushing 500 ponies to the wheels calls himself the stock block killer when he doesn't even know what his car sounds like at 5k rpm lol

:tup: sounds good! i think if it hits 300 rwhp i'd be happy :D

shooting for the stars, are we? :icon17:

hahaha i dont even got a Z :happydance:

That, and money, are exactly why I plan to wait a few years before doing any sort of Forced Induction. Let the nuts that have the money to do so, do so and blow up their stuff...if they don't, good for them! :)

Didnt GTM just Release a G37 coupe pushing 611 rwhp and 474ft/lbs just a lil while back on a stock block? Thats roughly 700+hp at the crank!!! We really need GTM or Forged performance to step in here and tell us what they have experienced with the G37's and that should give us an indication of the capabilities of our engines...

Besides the block, there's other limitations for RWHP - clutch/torque converter, transmission, driveshaft, differential, differential shafts/cv joints...

Limitation nahhh breaking points yes! The car will put down the power but the real question is at what point do those parts go kaboom and fail?

I will agree, however the limits of driveline components are more so a function of traction (too much of it). Given there are no issues with weakness in the driveline in stock form as you see sometimes in other cars, a Z with double/triple the stock HP won't necessarily break anything if the tires spin. Shock is what breaks parts, and that can happen in a huge HP-range.

Which begs the question...who has launched stock or bolt-on Z on proper drag-tires? :)

Trans onwards is a lot easier to figure out than the engines limitations. The new 6 speed box seems to be beefy from all accounts so I don't see 500rwhp for FI applications being any real issue but stock clutch etc will have to go.

I know an engine builder near where I use to live who got 580rwhp out of an old 4L toyota v8 though it was a pretty serious build, for the same engine for street use he thinks around 480rwhp as the one he built wasn't really tuned for street use. Besides being an open deck the VQ37 is better in basically every way and makes substantially more power stock. Considering Cosworth was getting 380-400rwhp out of the VQ35 those number should be much easier with the VQ37 not to mention more usable with the VVEL.

As the stock BHP is 330ish 380-400bhp should be easy if not more. As for the M3 engine are you talking about the latest 4L V8? The problem with that engine is that its engineered to be perfect how it is and doesn't have much room to improve in its current form without going to larger valves and bigger bore etc where as the VQ37 seems to have plenty of room to move up stock.

I guess we can only wait and see but I would imagine we will see 340rwhp+ N/A in the next 6-12 months. All depends on the design of the std of the head and how far the VVEL can be pushed.

Hey

Curious to know what kind of limits the block would go to with the Darton MID sleeves and possibly a billet girdle (I know ERL performance make them for the VQ35)...

The HR was designed after the GT-R motor with some of the same internals. The HR does handle boost just fine. If the VQ35DE can handle 400 safe, the HR can easily handle that safely. 450-500 I would say is the safe zone for any HR powered car, 3.5 and 3.7.

The other cars in Nissan's line up are not the same engine, yes they are a VQ, but they are completely different.

Maybe this is a dumb question, but I've seen several posts noting that an open deck is something desirable (and I assume this is in relation to the interface between the cylinder heads and the cylinders/block) - why?

Depends upon what you're shooting for. An open deck allows for a more free flow of coolant around the cylinders, but a closed deck is stiffer and can handle more abuse from pistons that have more off-axis loads. Open decks are often easier to cast, but they're also often not as accurate tolerance-wise.

I/H/E and a tune.

That was done a while ago, lol.

Translation: You're going to be spending alot of money in the long run whenever running forced induction on a factory N/A car.

Got a link to this 340rwhp+ N/A 370? I remember seeing a 300rwhp+ one but can't remember how far they got it. I can't wait to see 400rwhp N/A.

EDIT: The standard 370z gear box seems more than able to handle 400-500rwhp so just a new clutch there. No idea about the diff and rest of the drive train but if your not doing really hard launches I can't see it falling apart considering how power many older vehicles can handle on the standard drive train. The clutch is the number one thing that would need to be upgrading, after that I would think the diff before getting new cv joints etc, I haven't really seen any CV joints fail its usually the actual shafts from hard launches from what I have seen.

My pleasure. This one is actually ~345rwhp.

http://www.the370z.com/tuning/4594-i...o-results.html

A baseline of 302whp is a little too generous though

Yep, that's like only a 7 or 8 percent drive train loss....not likely.

Yeah the drive train loss seems a little low, 15-20% is more reasonable. Most stock dynos i've seen are in the 280-288 range which indicates a relatively low ~15% drive train loss.

On a dynojet that will be around 20 or so less. Those dynos always read high and need to be taken with a grain of salt.

"There are no small accidents on this circuit." -- Ayrton Senna
317.2 WHP & 247 ft/lbs TQ (Dyno Dynamics (4/22/09) | 330.2 WHP & 264.24 ft/lbs TQ (DynoJet (5/20/09))

^^^That's Semtex with no tune. That's the lowest reading dyno vs. the highest reading dyno. Maybe the Mustang dyno is the most accurate?

I dunno, I don't really care about numbers.

Yup, it's all about the %gains and area difference between the two curves

i dont doubt they can hit 500 whp safely on stock motor. But you have to look at what kind of manifolds and turbos are used. Im coming from FI'ed S2000s and before people thought the block was limited to 400 at most. Well while tuners push the limit and understand the car better they realize you can boost a lot more!

I see no reason for this block to be able to hit 500 whp reliably. **** in my S i can hit 400-450 with a stock block. What im curious is known what the max this thing can put down. Oh and open deck is fine for boost. A lot of engine builders use open deck builds on high hp (700+) cars.