[n37tt]

Well, the main problem with turbos espescially on the older skylines is turbo lag. If you slap twin t88's on a rb26dett, you literally wait till 7500 RPM before they spool properly, assuming they reach full boost. It'll make 1000 WHP, but at 9000 RPM. Obviously this isn't very useable power on the street as most of us dont' shift at 9000 RPM, or anywhere even near that on the street.

Well, this idea has been kicked around MANY times, but i'm surprised nobody has brought it up. Regardless of whatever technologies nissan is going to use, this is something ANYBODY who can actually afford a GT-R can do.

Bolt a twin-screw supercharger onto the engine. A twin-screw supercharger provides FULL SUPERCHARGER BOOST off idle, so imagine getting 8 PSI as soon as you floor it. The instant supercharger spool will allow you to spool up those rediculous turbos MUCH faster, and not to mention if your at ANY RPM above idle, you'll be seeing at least 10 PSI of boost from the supercharger and turbo.

Now, I've kicked around the idea in the past before on other cars. The only way this would work effectively is by having the two turbochargers FEED the supercharger. On a skyline, the supercharger itself will run out of huff up top, thats quite a common thing. On a skyline that can rev to 9000 RPM, a supercharger will kill any high end gains. Well if you have two turbochargers cramming more and more air into the supercharger at the higher RPM, and the supercharger compressing that boost even further by another 8 PSI, you will have a very fun car in deed.

Best thing about this? you need someone whos good at mounting a supercharger. Redo the piping which isn't that hard, and there you go. Very little lag. All this can be done for $7-8k if somebody actually develops a kit. You get response of driving a big block v8, but the high RPM of a v6.

BTW, the next GT-R engine will be a v6 more than likely. The body itself is much larger, and i'm assuming the engine bay will be much larger as well. You could dump a rediculous large turbo on each side of the engine and have the supercharger sit on top where the intake manifold is.

Did I mention you get the whine of a supercharger with the sound of beautiful turbo wastegates?

 

[tekknikal]

Well, the main problem with turbos espescially on the older skylines is turbo lag. If you slap twin t88's on a rb26dett, you literally wait till 7500 RPM before they spool properly, assuming they reach full boost. It'll make 1000 WHP, but at 9000 RPM. Obviously this isn't very useable power on the street as most of us dont' shift at 9000 RPM, or anywhere even near that on the street.

Well, this idea has been kicked around MANY times, but i'm surprised nobody has brought it up. Regardless of whatever technologies nissan is going to use, this is something ANYBODY who can actually afford a GT-R can do.

Bolt a twin-screw supercharger onto the engine. A twin-screw supercharger provides FULL SUPERCHARGER BOOST off idle, so imagine getting 8 PSI as soon as you floor it. The instant supercharger spool will allow you to spool up those rediculous turbos MUCH faster, and not to mention if your at ANY RPM above idle, you'll be seeing at least 10 PSI of boost from the supercharger and turbo.

Now, I've kicked around the idea in the past before on other cars. The only way this would work effectively is by having the two turbochargers FEED the supercharger. On a skyline, the supercharger itself will run out of huff up top, thats quite a common thing. On a skyline that can rev to 9000 RPM, a supercharger will kill any high end gains. Well if you have two turbochargers cramming more and more air into the supercharger at the higher RPM, and the supercharger compressing that boost even further by another 8 PSI, you will have a very fun car in deed.

Best thing about this? you need someone whos good at mounting a supercharger. Redo the piping which isn't that hard, and there you go. Very little lag. All this can be done for $7-8k if somebody actually develops a kit. You get response of driving a big block v8, but the high RPM of a v6.

BTW, the next GT-R engine will be a v6 more than likely. The body itself is much larger, and i'm assuming the engine bay will be much larger as well. You could dump a rediculous large turbo on each side of the engine and have the supercharger sit on top where the intake manifold is.

Did I mention you get the whine of a supercharger with the sound of beautiful turbo wastegates?

wow. well first of all, welcome to the forums!
your idea sounds very intriguing. on the one hand the logical side of me doesnt think its very likely to come out the box like that due to history, cost, etc. On the other hand, looking at the car itself, it seems very plausible. the hood seems much higher than on the Z/G, which required special hoods for some FI setups. in addition, the car is much wider, leaving more space on the sides of the engine. all in all the idea sounds like it could work well, and combined with AWD, would be absolutely monsterous on the streets. It would be very nice to see something like this make it to the streets...

 

[toykilla]

Welcome to the site.. Good topic for discussion. I would argue that Nissan would never do such a thing. Two small turbos that are fully spooled by 3k rpms would be a more likely option.

Let me wake up and come back to this topic.

 

[bonzelite]

good speculation. and welcome to the forums.

i'm more inclined to believe in an electric/electronically assisted spool-up w/ variable geometry TT setup, personally. it will be entertaining, at long last, to see who was closest in their guesses about the entire GTR package. some of us will have been way off, some close, some on the money. and some a combination. i will venture to say that you are correct 100% that the GTR setup, whatever it is, will be "zero lag." it must be zero-lag, or virtually zero, in response to the Porsche 911 TT/AWD which does have lag, but barely any. for sake of argument, the 997tt has no lag. and anything less than this standard appearing in the new GTR will not be acceptable and stand as an embarrassment to the GTR heritage and nameplate prestige.

 

[willy]

my money is on electronically assisted

 

[bonzelite]

yes. i will bet money it will be:
http://www.350z-tech.com/forums/Steady-sta...GTR-t17150.html

 

[theminel]

but I'm quite sure it's been done already on other cars, so anything's spossible (was it the Lancia Delta Integrale using this?? I read it on a Italian magazine last year but can't remember the car that used the SC to spool up the turbos )

 

[Ronin Z]

The practice of using a turbocharger and supercharger in series on the same engine is commonly referred to as "twin charging" and has been done many times over the years. In fact HKS used to market a turbo kit which was specifically designed to be fitted to the supercharged 4A-GZE Toyota MR2 motor.

The prime motivation behind twin charging is to have an engine that develops an impossibly broad torque curve. A secondary consideration is that having a supercharger already fitted to the engine allows the builder to employ a turbo much larger than would normally be possible with an engine of a given displacement. Which as we all know, big turbos tend to lead to big horsepower.

With that being said, it's rarely used because it's expensive and, at high boost levels, becomes a plumbing nightmare. Plus the efficiency is inherently terrible.

In any event, Nissan will produce a fairly seamless and well sorted setup for the GT-R. I’m sure it'll be some ultra slick engineering marvel... which will rapidly get yanked out by tuners and get replaced with some lag-happy Frankenstein setup that makes 1200 HP.

Regards,
Ronin Z

 

[n37tt]

I will begin by clarifying a few things for all of you.

Do I think Nissan will "twincharge" the GT-R? No. It's too expensive on a limited production scale to provide this kind of technology and still keep it under $100,000. Is any enthusiast whos going to mod their GT-R willing to do this? Of course. And here's why.

The twincharge setup itself isn't as hard as many would believe it to be. We've all heard the nightmares of plumbing, but it isn't that difficult, and the concept itself can be applied ot just about any vehicle. I stated earlier that the turbochargers should feed the supercharger, this itself is a very important concept. Most people reverse this, only to see the mistake that the turbocharger can suck a lot more air than the supercharger can blow air. Thus, the supercharger impedes airflow into the intake. Turbochargers feeding the superchargers will NOT have this problem, as lets say your turbos provide 10 PSI of boost, well, the supercharger will compress that 10 PSI by another 8 PSI (or whatever you have your pulley at) and you have 18 PSI.

At 9000 RPM on a skyline, your turbos will continue to spin rather easily because they are in their power zone, while the supercharger itself has lost its breath. But if you continue to cram more and more air into the supercharger, it gets rid of the negative effect of having no top end on a supercharger.

Plumbing isn't difficult at all, just take a look at this. (keep in mind this is for an Inline-6 RB26DETT Skyline)


Turbos suck in air like usual, which goes to the supercharger, which goes to the intercooler, which goes into the intake plenum/throttlebody. You SHOULD NOT use a blow off valve because the pressure relief is very abrupt and violent, you try to put on a BOV on a twincharge car and you'll see what i mean. The pressure relief must be consistent and steady, the best option is to rig a turbo wastegate for this. As the throttle is left off, the excess boost is re-directed into the supercharger intake and thus re-circulates. The supercharger uses the own boost it creates to power itself, thus reducing the amount of hp parasitic loss. I'm not sure about how much, but the theory sounds good. Note where the Bypass Valve is located, thats the only spot you can put it.

If you had $7500 US and someone good at mounting a supercharger. This shouldn't be a problem at all. Purchasing a high quality supercharger is I would say a must. Opcon Autorotor or Whipple makes some nice units. Use *ONLY* twin-screw superchargers, as roots isn't as effective and centrifrugal superchargers take WAY too long to spool.

Everybody says there will be virtually no lag, or very little lag. With this setup, there is not only NO LAG whatsoever, you'll have an impeccabe amount of torque available on tap at just about any RPM.

Imagine this, your on a race track. As you slow down to take a corner, your RPMS drop off to say 3000. Well, you have some larger turbos that dont fully spool till 5000 RPM. Well with the supercharger, your ALWAYS sitting on your base boost (which is whatever your pulley is at) + whatever boost your turbos contribute. In many cases, if your pulley is set at 8 PSI, your turbos will probably be pushing at least another 4-5 PSI at around 3000 RPM at least in the worst cas scenario. Your looking at never dropping below 13-14 (1 Bar) of boost at ANY engine speed. Well, if your sitting at 1 Bar at 3000 RPM, just think how much faster you'll pull out of a corner.

This technology has lots of pluses as well. You don't need variable geometry like the porsche do, you do'nt need to detonate fuel to spool up the turbos, and possibly causing damage to the turbos. It's like having an unlimited shot of nitrous all day long.

 

[toykilla]

I see too much going on there. Adding more components to an already complex system (turbocharger) is asking from problems. We are not running an RB motor. There are pros/cons to this.

Pros:
New light weight aluminum block
Torque!

Cons:
RB was built like a tank

I think the twin charged idea is cool, but it is not practical.

 

[scathing]

Its amazing how many people don't get the concept of lag, or they have a definition of it that differs from my understanding.

By n37tt's description of the twincharger you can see that in his cornering scenario the engine lag. It may not be as bad as if it was running just the turbos, but it will be there.

 

[bonzelite]

i just doubt Nissan will go twin charger. a turbocharged supercar from Nissan is a leap enough for most americans in the GTR buying range. you start slapping more go-fast stuff on it and it's just too unrelatable. and more failure prone.

but, hey, who the **** knows anymore what is up or down.

 

[waitin407]

I'd say twin charging of the GTR is a pretty far fetched idea and doesn't sound feisable on any level, I'd lean way more towards electronically assisted turbos to provide "lagless" boost and power delivery. I'm sure someone who has the money to blow (pun intended) would be interested to consider this avenue, but I think it would be very un-reliable considering the technology that we are all hoping is going into the development of this car.

 

[bonzelite]

i will say again that the GTR must feature --at all costs-- a virtual zero-lag turbo charging system or it will not be taken seriously. Porsche has already done it (with some very slight discernable lag, mind you), and if a later-arriving GTR does not exceed or at least match the responsiveness of the 997tt, it will be seen as a total failure of purpose.

in my opinion, the quickest and most efficient and cost-effective OEM solution to this will be electronically-assisted variable geometry turbos (assuming the GTR is turbo-charged at all).

 

[n37tt]

Edit.

 

[n37tt]

2/3.

That's a magical number that Ghosn has promised to deliver. 2/3 the cost, at 1/1 the performance. There will be some advanced technology going into the GT-R, thats for sure, but don't expect anything revolutionary. The original GT-R was less than 1/4 the price of other supercars, but performs like any true legend would. This next GT-R will do the same, but on its own term.

The twincharge concept isn't a difficult idea at all. The fact that some of you are afraid of it is a good indication that it is a good solution to our lag problem. This idea will probably never make it into production, although it did with the Nissan March (1.0L SC/TURBO). It's something that any GT-R owner can do right now to help themselves.

Do'nt tell me that if you spend $75k USD you can't afford $10k to bolt on a supercharger to this. Of course, you need to mod the GT-R to see the full benefits, but having high potential in mods is what the GT-R is known for.

I garantee you, a twin-turbo supercharged gt-r will be nearly invincible on the streets. The grip of the attessa, the handling of the lotus tuned suspension (rumors of course), and the high rpm of the cosworth powered engine will send most people into seizures. Now, add the supercharger and your powerband seemingly limitless.

Even if nitrous costs $10 to fill up, it still wouldn't compare to the power/cost ratio of a bolton supercharger.

Just look at it this way, the GT-R will probably be at least $20k cheaper. Bolting a supercharger and doing some custom pipe work is much cheaper than doing this on a '911 Engine. You don't need to work for Porsche to realize that. Porsche doesn't have that luxury for modification without MAJOR dollars. GT-R's do.

I don't care what kind of variable geometry turbo, etc etc etc Porsche has. It doesn't compare to having a blower providing that blast of 8-10 PSI at anything just off idle. Nothing porsche could do would even compare to that, unless they put a blower on themselves.

I'd like my world to dissappear as I reach redline. All 9,000 revolutions of it.

 

[waitin407]

I would have to go with bonzelite on this one with the variable turbo's rather than sticking so many belts and blowers and suckers under the hood to get the power and lack of lag that the GTR should have to compete with the high-end cars.

 

[bonzelite]

yes, and it is important to realise, too, that ferrari, mercedes, and porsche are getting astonishingly high torque and horsepower curves with naturally aspirated engines. for example, the amazing Ferrari 599GTB is N/A, delivering a shocking and neck-snapping 448 lb/ft of torque @612bhp. Porsche GT3 is N/A and it's "only" 6cyl. and it is a homologated race car that happens to be street legal. and it's rated 300lb/ft tq @415bhp. non turbo. this already proves that forced induction is not necessary but is a matter of design ethos and choice, as there are pros and cons to both n/a and turbo and supercharged, and twin-charged.

certainly, the tt setup for GTR has become a tradition. and i am not saying that the tt setup must be sacred and "we've figured them all out." i'm not saying that at all. i am just as open to new stuff as a non-purist would be. but i am not convinced of an alternative at this point. i'm just not.

a large part of my bias comes from the years of Nissan's racing and track time since the rise of the racing VQ variant series to JGTC in the R34 GTRs (of all cars). and those were not supercharged. to some extent we must look back at heritage to see where the GTR may be going next.

supercharged GTRs may emerge as time goes by, but this in my opinion will be in the domain of the aftermarket only, at least at the very outset. will Nismo develop a GTR-specific supercharger? i have no idea. i've never really seen Nissan as ga-ga over a supercharged engine. but all bets are off. the secrecy is killing us all.

 

[scathing]

certainly, the tt setup for GTR has become a tradition. and i am not saying that the tt setup must be sacred and "we've figured them all out." i'm not saying that at all. i am just as open to new stuff as a non-purist would be. but i am not convinced of an alternative at this point. i'm just not.

The KPGC10 was NA, and RWD. The only thing it shares with the R3x series cars (aside from being the 2 door version of a sedan) is an inline 6 engine, the stove-top lights and the red "R". And that it was bloody fast in its day.

The R33 and R34 were design enhancements of the R32. The RB26 was tweaked, but fundamentally the same. Same with the ATTESSA, which got software and minor hardware upgrades but wasn't a complete revamp. There was no major change to the suspension design (its not like it went from a live rear axle to IRS, or from IRS to inboard).

In software terms, mechanically the R33 and R34 are "dot releases" of the R32. Tweaked and updated, but no fundamental changes.

In that way, having a TT GT-R isn't exactly a tradition in my books. It hasn't been there since day one, and the only reason its been retained for so long is because they were working within a limited budget and so couldn't "clean sheet" design the R33 and R34 when the R32 reached the end of its life. The next GT-R is a clean-sheet design, and so if they can make good power while keeping it NA I think they will. With ever tightening emissions Nissan has killed most of their famous turbomotors (the FJ, the RB and the SR). Their modern turbos are either JDM-only, or in SUVs where the emissions restrictions are far lower. The next GT-R will not have the luxury of either exemption.

However, the stove-top lights are a GT-R tradition since the original. As is being the fastest Japanese production car around a racetrack. But twin turbos are certainly not like Porsche's rear mounted boxer for their 911, the fiberglass body on a Corvette, BRG on any English sports car, or Mazda's rotary in their RX series of sports cars.

 

[bonzelite]

i'm fully aware of the older GTRs being N/A. that is not a secret.

however, the RB series GTRs were manufactured longer, and in greater numbers than any of the C10 or C110 series-based GTRs. and with greater popularity as mass-produced streetable cars. personally, i do not consider a tradition necessarily existing from day one. but, rather, it can come about as a matter of course. in my opinion, "godzilla" really put the GTR on the map like never before seen.

today, the GTR is synonymus with twin turbo even though it may just as welll be N/A in it's new incarnation, as i have postulated in other threads and in other posts, hence my very mentioning of the GT3 Porsche and the 599GTB Ferrari --no turbo necessary --and those cars outperform any stock GTR that has ever existed.

certainly, in accord with you, the GTR could very well have an N/A V8, as is seen in Mercedes Benz and Aston Martin. indeed, turbo charging is not necessary. this has been known for years. and most indeed, twin-charging is absolutely unecessary, and, in my view, overkill and gimmicky.

i'm saying if the GTR is at all turbo charged, we will see electronic assist w/variable geometry --IF it is turbo'd at all. my bias is such that i feel Nissan will directly attack Porsche-related benchmarks, specifically the 997. whether they go N/A as in the GT3 or tt as in the 911 has yet to be seen. but the 911tt is AWD, too. and past "tradition" has been AWD for the GTR. so it appears on the surface that Nissan will "do it again" and attack the 997tt at it's own game. this means AWD and tt, continuing with the full monte' Gran Turismo configuration. but...

if it is a V8, the chances of TT, for me, go way down. if it's V6, TT looks more likely --keeping with "tradition." and i think by large measure, this is what most people want, as it is relatable, and race-proven (although personally i am hoping for a V8TT).

but since, as you say very well, this is a "clean sheet" GTR, pay particular attention to Ferrari and Porsche GT3 and Aston Martin. as this may very well be the next paradigm. why? because the best cars in the world are doing it, and the GTR has now graduated.