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Discussion Starter · #1 ·
thinking about how much an 800+bhp Skyline lags (or relies on sky-high RPM and in any event delivers power in a peaky punch), and how I'd like to see a usable 800bhp in my car, as well as reading A. Bell's books on engines and forced induction lately - he's a huge detractor from using turbos on the street, and argues fairly convincingly that supercharging is the way to go (makes some other arguments about turbocharging being the most common form of forced induction due to marketing/economics instead of being the best method)...and being bored with a car that works...

How about developing a Lysholm supercharger kit for the Skyline GT-R? We could use this thread to bounce ideas around and sort out issues.

First, we'd need to select a blower. They are compact enough to fit where a topmount turbo would go, and with no turbo plumbing at all, that opens up a lot of space there. Most screwchargers are 22~25cm in width, and vary mostly in length, 30~45cm. Heat shielding the exhaust headers would be required, or at least a Good Thing.

Second, where would the drive belt come from? The front? If so, the air intake is in the rear....how about building an airbox behind the glovebox (and also behind the firewall) and have the box suck in air in the same way as the climate system does (beneath the windshield wipers), just on the passenger side. Then connect the rear of the supercharger to the box..on the hot side of the firewall. Cold air intake.

Going back to the drive belt - if the drive could be taken off the flywheel, then the screwcharger could be mounted backwards and the air intake filters could be in front as normally seen.

Screwcharger output: from the bottom...the output pipe would run near the exhaust headers going to the intercoolers, but then again, come to think of it, so do the pipes of topmount twin turbos. If we decided to throw out intercooling altogether, we could mount the screwcharger upside down and then send the air across the top of the engine like an RB25.

MAF or MAP?

The only two downsides to a screwcharger deal with cost - constant heavy parasitic power loss, and cost of the unit. But the second...well, in the GT-R game power comes at a price!

Otherwise, the unit can push enough air to more than triple the displacement of the engine, with power coming in VERY early.

Could be a lot cheaper than stroker/RB30 kits, and we could dump the FMIC.

Maybe a 2.6 liter engine simply can't drive a screwcharger at low RPM?
 

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If the intercooler were to be ditched then there is not much chance of getting anywere near 800hp with a supercharged 26.
At the end of the day there is no subsitute for cubes, and since superchagers take a lot of power to drive they are commonly used on big engines with great results.

What your after is a nice flat power curve with good power down low and huge top end. It could be done with nitros controlled by the ecu and a big turbo, or with antilag but I dont think there would be much chance of a 2.6 litre engine driving a big enough supercharger to make 800hp and still have plenty of grunt down low.

If you were to supercharge, the easiest place to run the drive belt from would be the front of the engine. It wouldnt be simple tho as the effect of a belt that big running off the harmonic balancer could have adverse effects.
 

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If the intercooler were to be ditched then there is not much chance of getting anywere near 800hp with a supercharged 26.
Correct, especially as a Lysholm SC is not as efficient as a Turbo charger, meaning more heat for the same boost, and therefore a need for a bigger IC.
 

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Discussion Starter · #4 ·
according to whipple a screwcharger is equally efficient as a turbo, the problem is in the raw horsepower required to drive the thing. basically what I'm challenging is the notion that turbos are inherently the best way and that we've been using them more out of convention,habit and cost efficiency..$5000 for a compressor doesn't look so good next to $2000 for turbos especially from nissan's point of view..but for the enthusiast it's worth looking into
 

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Not quite true.

The best Screw SC's are comparable with older TC's. And only over a limited speed range (the slow end).

The modern turbo is more efficient and more importantly, has a wider efficiency island at the point where it matters.
 

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Superchargers are less efficient because of the power loss to the wheels that is used to turn the supercharger,simple. I would never use one on an engine less than 4L trying to make over 700hp but I have to say I love the supercharger on the Mini and am considering putting one on my Lupo, but the costs are huge, I'm looking at £5K bill.
 
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Looked into this a number of time s, never managed to make myself believe it will work, so it has never been started.

S/C,ed a 33 GTS worked out pretty good, but to make big BHP from a S/C on a small displacement motor will be very hard work. Got some figures around somewhere, will try to sort them out.
 

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Positive displacement blowers are a dead end IMO..

Whipple claim 30psi is possible but take a look at a compressor map for a whipple. The PEAK efficiency is only around 55-60%! At high boost levels it drops off sharply.

Best way to combat lag is more displacement IMO. Talk to rob @ rips about VH or TB conversions ;)
 

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Discussion Starter · #9 ·
well, I put it out there and figured there must be some reason why it hasn't been done (like Claire's R33 is the only example I know of).

I handled lag on the drive home tonight by...revving the shit out of my engine! Did in a CL63 AMG twice in a row off the line and once running chaser (starting behind him). That third time when I just reeled him and sailed past while on boost in 3rd - no replacement for displacement eh? :chuckle:
 

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Now that is my next engine project. The Merc 63 engine with a pair of decent turbo's.

I just love that engine, one of the best modern engines in existance today. Pity it is wasted in a 2 ton tank.
 

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Can't see it working either....Too smaller engine to produce that sort of power from a supercharger....If you could crack the twin charger setup, that would do it.

HKS made a twin charger kit a few years ago for the 4agze, It came with a electronic box to adjust the switch off point for the clutch on the supercharger, and a turbo about the size of a T04!

....But me, I would be looking at something like a RB30 (or RB33 if you had the dosh) and a couple of these Hybrid 2530's from NZ!! 750hp at all 4wheels....And shat loads of torque!!
 

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Discussion Starter · #12 ·
no power until 6000rpm? no thanks :p
 

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Best way to combat lag is more displacement IMO. Talk to rob @ rips about VH or TB conversions ;)
If someone made a VH iftting kit with a pair of plenums and manifolds for a pair of say GT-RS you'd have something pretty impressive. I'd guess that you start to see boost from 2-2,500. Could potentially weight less than the RB but would certainly pull the weight further back in the engine bay.

When I looked at the Whipple chargers they were very expensive. Several thousand pounds for just the unit. A VH would be cheaper to buy so the increased fitting costs could well balance out.
 

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no power until 6000rpm? no thanks :p
I'm pretty sure that with a RB33 (700cc more) you would be knocking back to 3500-4000rpm

What you are talking about is possible....But hugly complex, just drop a V8 in as mentioned then!!
 

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Discussion Starter · #15 ·
the problem with the VH41 and twin GT-RS turbos is the aluminum block. Can that block really take 200bhp/liter output? The VQ35DE is a very well-developed engine, but as soon as builders go for big boost, they have to sleeve the block. That gets complicated.

But ATTESA does exist for the VH41DE (JDM car, forget which model, I think Cima or President or something), so adapting it into a GT-R while retaining AWD is possible.
 

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From what I've seen (which isn;t that much to be honest) people can get silly outputs from those engines. I've seen boats (with these engines) with 900bhp odd quoted.

I know that the Lexus/Toyota V8s (which are very similar I understand) don't have any problems producing silly power figures.
 

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Discussion Starter · #17 ·
hmm, I'll ask around on Nissan forums, see what has been done with twin turbo VH41s. Could be an interesting swap if it doesn't add much weight on the front axle.
 

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Kismet, im doing it ;)

The engine itself is a fair bit lighter than an RB. Easy to move it around on the floor on your own anyway.

Power outputs in excess of 1000hp are possible. Set of forged pistons and some of the aussie power boat guys are producing that. I think more should be possible if you are a total nutter.

There was a 4wd Cima with a front diff in the sump, you need to really think about gearboxes though, as the kind of torque a 4.1 turbo motor can produce will render any conventional gearbox scrap pretty quickly!
 

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Discussion Starter · #19 ·
you've got my attention! lighter, more displacement, minimal internal work needed?

With a V8, only one exhaust option to go with - SIDE EXIT, both sides!!! :D
 

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kismet,
last year I developped a celica 4wd with a 3s-gte running a GT40 and a mercedes eaton supercharger (the one with the magnetic clutch from the 2.3 liter 4 cylinder mercedes). The car goes very very well. It is responsive as hell and has boost in all gears under all situations. The supercharger operates from 2000 RPM to 4500 RPM the turbo from 4300 RPM to redline.
I'm currently building a 2jz-gte with a GT42r and a 3.2 mercedes supercharger (lysholm alike) also with magnetic clutch. Here are some pics:

 
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