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Discussion Starter #1

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Thanks for posting that article. It has been awhile since I have drooled over a car. I saw the video of the first Option Stream Z, but was not aware of who owned it or the true forces behind its making. I am jealous of that guy. Cruzing at 200mph in 5th gear sounds like a good ol' time :)
 

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Yeah thanks.

Some serious moula has been spent there!!!!!

Looks like they thoroughly built the motor (not just a 'tune') to get some awesome power.

"I’m pretty sure the JUN engineers thoroughly went through this VQ35, balance and blueprinting every piece to exact tolerances. I wouldn’t be surprised if this 3.5 liter has gotten a bump in the displacement category and now houses a few more cubic inches under the hood. "

Whilst on F/I and the VQ engine I also found this little snippet of interesting info:

It is on the G35 May 2004 issue (runs the same VQ motor as the zed).

It was also interesting to see what they said about F/I and the VQ engine.

" The stock VQ35 engine was not designed for induction duties so beefier Crower rods were matched to Arias pistons to bring the compression and reliability to an acceptable level."

Seems F/I costs alot more than just buying a kit!

I believe this statement is more than backed up by all the posts on all the 350z forums of the guys that have blown motors.

Cheers
 

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Discussion Starter #5
MickeyBoy Wrote:

Looks like they thoroughly built the motor (not just a 'tune') to get some awesome power.

When your planing on getting this much power out of an engine you dont have any other choice but to thoroughly build up the motor. Show me one example of a production car which was 'just tuned' to get an increase of 500rwhp over stock output.

Seems F/I costs alot more than just buying a kit!

It depends on how much power you want and which kit you get.

If your happy with 300rwkw (400rwhp) then you can get the APS TT kit and providing you maintain the car correctly, it should be fine. Look at the APS TT test Zed they have been running it above this output for a long time without problem. If you wait till the APS kits all around the world have been installed and running for a while then hopefully we'll have more information to back this up. But to be safe if you want more than the stock output of the kit then you should look at upgrading the internals.

BUT If you cant afford to fix it if breaks then dont do it, its that simple.

I believe this statement is more than backed up by all the posts on all the 350z forums of the guys that have blown motors.

I think you will find that most of those blown motors are from the Greddy TT kit which is not a complete kit out of the box so you will definately have to spend more money to get a safe reliable setup with this kit. The Greddy kit is lacking on a number of fronts out of the box. Fuel System, Ignition Timing, Shielded Crank Sensor, BOV, Oil Pan etc.

Also alot of the blown motors in the states could have been caused by scattered ignition, a result that APS noticed when boosting our motor without a shielded crank angle sensor wire. So there havnt been enough motors running without this problem to clearly define the limits of our motor. Time will tell.
 

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Did you overlook this statement?

" The stock VQ35 engine was not designed for induction duties so beefier Crower rods were matched to Arias pistons to bring the compression and reliability to an acceptable level."

It's not my words!

Such high compression in VQ engine, not ready made for F/I..

Yes time will tell????

I am not convinced of any turbo kit. Whether any of them have run them for long enough or on what they have called 'stock' engines is another story!

Who has had a chance to scrutinize them? Furby's run left, right & centre.

And yes, time will tell???
 

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[/quote]

MB - what was the context of this statement. That is, just how much psi were they palnning on running with the stock motor and what power targets did they have in mind?
 

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"The heart of this system revolves around a single Garrett ball bearing snail mounted to custom manifolds which produces a maxed out 410 horsepower".

13psi of boost is regulated by the new HKS EVC which also serves as an in cabin boost gauge.

Answers!

The statement they made about the VQ not ready made for F/I was smack bang at the start of the article. So I assume they saw that any decent power gains thru F/I (300kw or more) meant stock internals had to be beefed up.

However, they say the turbo maxes out at 410 hp but also then state 13psi boost?
Must be achieving more than the 410 hp.

Still, doesn't change the reality of the VQ needing beefier internals for safe F/I.
 

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Discussion Starter #9
MickeyBoy Wrote:

Did you overlook this statement?

“The stock VQ35 engine was not designed for induction duties so beefier Crower rods were matched to Arias pistons to bring the compression and reliability to an acceptable level."


Obviously the VQ35 engine isn’t designed for forced induction, it’s a NA tune motor. When Nissan was designing it they were not thinking about a turbo or supercharger.

And needing to upgrade the rods or pistons, as I mentioned, its dependant on what you want to achieve, if you want to run 1psi of boost producing a bit more power than stock then you don’t need to upgrade pistons and rods, if you want to run 24psi of boost producing 700hp then you will need to upgrade the rods and pistons, somewhere in the middle there is a safe limit or compromise between power and reliability. And once this limit is confirmed it’s up to you whether you want to go pass it or not. APS has chosen 400rwhp to be a safe limit to set all their TT kits at based on years of engineering experience, testing on their own 350z and the fact that allot of people will putting it in their expensive cars, as a result I think they would have erred on the side of caution.
 

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Maybe they erred on the side of caution with the 400hp limit, or maybe that is where the marketing people needed the 'safe' limit to be?

As a daily driver of the zed, I don't think I would feel safe with any TT kit boosting power to 400hp without knowing that my engine was built to handle it. I can't take the word of the people building any kit, they just have too much of a vested interest in talking it up as 'safe'.

It's the same with the zed now as it was with the wrx's years ago. Many kits came to the market, all 'safe', and many motors blew! Do some research and see for yourselves, then you will see where I am coming from.
 

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Discussion Starter #11
http://www.jtuned.com/content/templates/st...eid=34&zoneid=2

This is the link to the article that MickeyBoy is referring to.

Some of the choices made by garage who worked on this car are questionable and the resulting power figure achieved is very disappointing. I would not use this article as a guide for anything.
 

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Discussion Starter #12
mickyboy wrote:

Maybe they erred on the side of caution with the 400hp limit, or maybe that is where the marketing people needed the 'safe' limit to be?

Well they have invested around $380,000+ into development and testing this kit so to then let the marketing department chose the boost level would be a bit silly from a business point of view but I understand what your saying.

As a daily driver of the zed, I don't think I would feel safe with any TT kit boosting power to 400hp without knowing that my engine was built to handle it. I can't take the word of the people building any kit, they just have too much of a vested interest in talking it up as 'safe'.

Thats fair enough, FI isnt for everyone.

FYI the Unichip does have a fuel, timing and boost control so you can indicate the state of tune you wish during installation. i.e Take out timing, richen up air fuel ratio and reduce boost. I personally wouldnt mind trading 50hp for a extra bit of safety margin.

It's the same with the zed now as it was with the wrx's years ago. Many kits came to the market, all 'safe', and many motors blew! Do some research and see for yourselves, then you will see where I am coming from.

I see where your coming from but I think you need to take each example as a new one. Do your homework so you know what is acceptable for your engine that way you dont have to rely on what a company says it 'safe'.
 

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Scary, all starting to write like davidm!

Yeah, I'd rather let someone else be the guinea pig for these kits!

Remember, these F/I cars will be owned by people, not companies that can write off a blown motor as R & D.

Would like to see them running for a few years!

Why do you say that the garage made questionable choices????? in post 11.
 

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Discussion Starter #14
Scary, all starting to write like davidm!

Ive been writing like this since I bought my car two years ago. But your very observant as it is like Davids.

Why do you say that the garage made questionable choices????? in post 11.

Their choice to replace the 'drive-by-wire' system with a mechanical throttle body. I have heard of no one having any problems with this system and some are running up towards 700hp. Then there are the things you loose by doing this; throttle response and the traction control system.

Also the fact that they've built the motor up with rods, pistons, cams, fuel system, exhaust, designed a custom single turbo kit and it maxed out at 410rwhp. This number is probabally a bit less on an Au dyno.
 

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The guys that did the G35 is Blast racing. They actually built a Lexus sc400 that did 7.38 sec for the qtr mile & one some award for that in 1991. So they are no backyard boys.

So they went around tuning the G by ditching the drive-by-wire
"the new G comes with a “drive by wire” throttle system which makes it quite difficult to tune due to the computer having so much control. Blast ditched the stock unit in favor of a mechanical throttle body and custom plumbed throttle cable"

Just a different way to get around the ecu & tuning.

They built the motor up because they want the thing to last!
Interestingly, they get the same power (410hp) as APS keeps stating is 'safe' without having to change any internals. (given one is the G35 & the other on zeds, but essentially the same motor)

I would imagine that they (APS, Greddy, etc) would not sell many kits if zed owners were told that they would need comprehensive engine upgrades to enjoy a happy, safe and long life with their chosen car.
 

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Discussion Starter #16
Just a different way to get around the ecu & tuning.

It’s a different way but IMO if you are doing it to get around the ECU it’s an unnecessary way which would cost more money and result in a loss of functionality.

Based on your posts here I think you would not be happy if that was your car and they did all that extra unnecessary work which loss some functionality, took longer to do and it cost you more money when they could have just left it stock without issue.

For your info they didn’t have to get around the ECU as the ECU solution they used was a HKS FCon V-Pro, which is one of the best ECUs for tuning engines. So there must have been another reason like they thought the stock one was a restriction and the only larger Nissan throttle body was mechanical.

They built the motor up because they want the thing to last!

I wasn’t questioning why they built up the motor, I was saying that they've done all this work and only managed a MAX of 410hp. Once again I think if you (MickeyBoy) paid for all this work and it was maxed out at 410hp when guys with a stock kits are getting the same numbers and have the potential for 700hp+ when they build their motors you would not be pleased.

Interestingly, they get the same power (410hp) as APS keeps stating is 'safe' without having to change any internals. (given one is the G35 & the other on zeds, but essentially the same motor)

Not interestingly at all because THERE IS NOT CORRILATION BETWEEN THE TWO.

I don’t think you've been reading, APS has invested more than $380,000+ into the DEVELOPMENT and TESTING of their twin turbo kit and the other was a once off small single turbo custom kit made by some tuner who has possibly invested zero dollars. You can't compare the two.

I would imagine that they (APS, Greddy, etc) would not sell many kits if zed owners were told that they would need comprehensive engine upgrades to enjoy a happy, safe and long life with their chosen car.

No they wouldn’t sell as many kits if that was the case, but thats not the case.
 

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Single snail producing 410hp with 13psi boost and we are comparing to a TT producing 400hp with 7.5psi. Can you even compare boost levels and subsequent power between a single and Twin turbo systems?

Perhaps the internals were upgraded as the owner had TT and 650hp in mind down the track as stated towards the end of the article.
 

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Mate, I posted #15 responding to your comments about them being some small tuner or the like (reading between the lines).

I couldn't give a rats arse about them, but they did win the 01 IDRC National Championships (whatever they are).

Nah, on second thoughts, they don't know jack about anything!

Sorry to try and bring some actual non marketing, 'safe', 'tune', no need for upgraded internals, yes VQ engine is low compression perfect for F/I, never a blown motor, non brainwashed thinking to the table!
 

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Discussion Starter #19
mickyboy wrote:
Nah, on second thoughts, they don't know jack about anything!

Im sure this isn’t the case but even the most experienced tuners will not always make the best decisions when their actual experience and knowledge on a specific engine is limited or zero.

mickyboy wrote:
Sorry to try and bring some actual non marketing, 'safe', 'tune', no need for upgraded internals, yes VQ engine is low compression perfect for F/I, never a blown motor, non brainwashed thinking to the table!

MickeyBoy, what you were saying in your posts is that the VQ motor needs forged internals to get safe reliable forced induction.

MickeyBoy Wrote:
"Still, doesn't change the reality of the VQ needing beefier internals for safe F/I."

What I was saying is that there is a reliable limit somewhere and that more time will show us exactly where that limit is.

mchapman wrote:
"And needing to upgrade the rods or pistons, as I mentioned, its dependant on what you want to achieve, if you want to run 1psi of boost producing a bit more power than stock then you don’t need to upgrade pistons and rods, if you want to run 24psi of boost producing 700hp then you will need to upgrade the rods and pistons, somewhere in the middle there is a safe limit or compromise between power and reliability."

These are our opinions.

Manufacturers build a certain amount of extra strength into their engines so they can withstand a certain amount of abuse and run under extreme conditions (Fact). So it’s just a matter of finding out how much more abuse they can take without compromising reliability.
 

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Murray, I think you are forgetting one thing. No two engines are going to be the same. Some are going to be stronger some are going to be weaker. You don't want to have one of the weaker engines and do FI on it. And in an N/A engine like ours the tolerances are built with that in mind, that some engines are going to be weaker and other will be stronger.

Right now I'm of the opinion that the only relible way to increase power in this car, without changing internals is to go N/A. If you decide to go with F/I, I'm of the opinion that the motor has to be build.

Also you guys are forgetting that relible might mean different things to different people. Some people want a weekend car which they can drive fast on weekends. What I want is a car that can drive 25,000km+ a year and so I can step on the loud pedal every day wihtout worrying that the engine will blow.
 
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