Q45 Supercharger Project: From Conception to Reality.

[elwesso]

Im not exactly sure what youll "get" as its all up to the customer to decide... It will include everything you need, sans ECU as you have to get that thru JWT (or one of our fine sponsors)

The SC should come ready to bolt on.

[Heath]

So since my birthday is coming up on Friday you're going to give me one for my upcoming acquisition right...

[MJC]

I understand you're going to be limited by the injectors right off the bat at around 400whp...

I'm wondering what the next road block would be...fuel pump is an easy fix...the question is, does the engine run into any power issues above 400whp...what about 500whp?

I'd like to take the car to a nice decent power level and keep it there...I'm really not trying to build the motor or anything crazy at this point in time...but if I'm told that everything is fine aside from the fact we are limited by the fuel system and compression, I probably wouldn't have a problem putting a fuel system and custom thicker headgaskets on the car to turn it up.

In which case the 350-375whp limited M90 (even the M90s [ported] probably wont crack 400, although I could be wrong) wouldn't be enough for what I'm looking for...I'd probably go with a centri blower like a Procharger.

Just trying to gather information. Great job pioneering the kit.

[elwesso]

Another problem you run into is the high compression ratio... Really you cant do much more than that without running into major downfalls.. At least all the major hurdles happen together...

Youd want to upgrade to lower compression pistons and then some 550CC top feed injectors... Then fuel management becomes a biznitch

[Heath]

Ignoring my question won't make me go away!!!

[elwesso]

Ignoring my question won't make me go away!!!

Curses... *covers face* if i cant see him, he cant see me...

I actually had to put my kit on hold due to financial difficulties... We need someone to step up to the plate and be number one.. if anyone wants the FIRST supercharged Q45, email me for COMPLETE details.

[PoorManQ45]

In which case the 350-375whp limited M90 (even the M90s [ported] probably wont crack 400, although I could be wrong) wouldn't be enough for what I'm looking for...I'd probably go with a centri blower like a Procharger.

The ratings that are put on Superchargers and turbos, in terms of HP maximum, are NEVER accurate. It all depends on the engine. In this case it "only" takes 4~6psi to make 350~400HP. Now compare that to an SR that requires 15~20psi to make that same power

[MJC]

Yeah I know the compression is something that has to be overcome for any type of decent boost on pump gas, my question was more of, if I dealt with that...what would be the next thing to BREAK. Maybe this information just isn't available yet because no one has taken it this far, just I didn't know if you had any clue how strong the bottom end is, or transmission after the upgrade, or differential, etc...

Fuel management isn't TOO hard to overcome, I believe in some of the Japanese E-Manages that I have sold I've seen that they have an application listing for the Q45, and an E-Manage is a pretty inexpensive fuel management system and does a damn good job. My only worry would be a timing map suited for the boost, but that obviously would be taken care of with the JWT chip upgrade.

[PoorManQ45]

Need a Level 10 transmission rebuild if you want it standing up to the increased HP/Tq. The Rear end should be fine.

Bottom end is supposed to be really strong. IIRC the next weak link is the rings. They're good for ~500HP

[MJC]

The ratings that are put on Superchargers and turbos, in terms of HP maximum, are NEVER accurate. It all depends on the engine. In this case it "only" takes 4~6psi to make 350~400HP. Now compare that to an SR that requires 15~20psi to make that same power

Trust me my friend, I understand that paper numbers don't always agree with dynos, but you are incorrect in saying it all depends on the engine. I am BY NO MEANS a supercharger expert, but I do deal with many turbos, on many engines.

The reason it 'only' takes 4-6psi to make 350-400hp is because of the size of the engine (thus why the 2.0 SR needs so much more). The reason I brought up my earlier point of the larger M112 is not only for more power capability, but it will make the same horsepower at a lower boost and lower intake charge...thus safer for the engine. A larger compressor will flow the same amount of air at a colder intake charge, thus more dense, thus more horsepower.

This is the reason that if you put a GT28RS on an SR20, it's not going to make nearly as much power as the same engine with a GT35R at the same boost.

While you may say that the M90 is more than capable of 6psi (which I agree, it is), it does have limitations that will approach very quickly if trying to pass 350whp on your way to 400whp. The GM 3800 guys have been running these things non intercooled up to 11psi (so I am told) and go higher than that with one obviously. My only concern is that I have never heard of one making more than 370ish whp without nitrous. (again, it's very possible that they have, I just don't personally know of one).

11psi on a 3.8 liter would 'roughly' correspond to 9.3psi on our 4.5 liter, which is more than I'd want to run on 10.2 compression w/ 93 octane anyways, but they run this on an 8.5:1 compression motor that with an efficent compressor will gladly stand up to 17-18psi on 93 octane on a daily basis with a safe tune.

What this says to me is that this M90 is extremely inefficent. And again, I applaud the drive to make this kit, I'm just trying to play devil's advocate so I hope you don't take offense to any of my comments. Hopefully someone that knows more about this blower than I do can step in and set me straight but if my observations/assumptions are correct then *I* personally would think that either the M112 or a centrifugal supercharger is the better course of action.

Of course, just my thoughts on the matter after one day of thinking about it.

[350zQ45a]

This is all from Mr. Knight

" THE REASON I CHOOSE THE M90 IS THAT IT CAN SPIN FASTER THAN THE 112, AND FLOW NEARLY THE SAME AIR. THE GM VERSIONS CAN HAVE PULLEYS MADE AS LITTLE IS 2.25", SO AIRFLOW IS NOT A CONCERN. ALSO, AN AIR-TO-WATER INTERCOOLER SPACER IS AVAILABLE FOR THE GM3800 SERIES 2 BLOWER. THEY RAISE THE BLOWER 1" AND WITH A BUILT ENGINE WILL DROP DELTA RISE 150 DEGREES @ 15 PSI BOOST. THE GM CARS ARE RUNNING 11'S. SEE ZZPERFORMANCE.COM"
Modified by 350zQ45a at 11:16 PM 5/24/2005

[350zQ45a]

I WILL SHARE WITH YOU THE BLACK ART OF RACE-PORTING AN EATON. IF DONE THE WAY I SHOW YOU, THERE IS AN EXTRA 8% ADIABATIC EFFICIENCY HIDDEN IN AN EATON ALLOWING FOR 20+ HP GAIN AT 5 PSI, AND ABOUT 50 MORE AT 8-10 PSI. THE Q WOULD REQUIRE WATER-ALCOHOL INJECTION TO RUN ANYTHING OVER 5-6 PSI BECAUSE OF THE HIGH COMPRESSION. FORTUNATELY, THE W/A INJECTION IS AVAILABLE FOR $100-$150 ON EBAY ALL DAY.

[350zQ45a]

WATER/ALCOHOL INJECTION IS GASSEOUS INTERCOOLING, AND EXTREMELY EFFECTIVE. THAT IS WHY JACKSON RACING RECOMMENDS IT ON ANY KIT OVER 5 PSI. I HAVE USED IT FOR YEARS. IT ALLOWS FOR HIGHER BOOST LEVELS WITHOUT THE PRESSURE DROP THAT AN INTERCOOLER CREATES, AND ALSO ELIMINATES CARBON BUILDUP AND HOT-SPOTS IN THE COMBUSTION CHAMBER.

[350zQ45a]

THE FORMULA IS SIMPLE:BOOST + 14.7/14.7 = PRESSURE RATIO. P.R. X STOCK HP = BOOSTED HP. ADD EXHAUST, FILTER, AND TUNING FOR AN ADDITIONAL 7-10% POWER. DRIVE POWER IS CFM X PSI/229. SO:280HP STOCK. 6 PSI. EXHAUST, AIR FILTER, AND CHIP.6+14.7/14.7 =(1.41 X 280) + 10%=HP - DRIVE POWER. 500CFM X 6 PSI /229= 13HP. SUBTRACT ANOTHER 5HP FOR FRICTION LOSSES, AND YOU HAVE 416 FLYWHEEL HP. THIS FORMULA IS ALSO ASSUMING WATER/ALCOHOL INJECTION OR THE DRIVE POWER LOSSES FROM SUPERCHARGER EFFICIENCY LOSSES WOULD BE 40-50HP INSTEAD OF 13.

[PoorManQ45]

It's a high revving DOHC engine, that has to move 4,200+ pounds off the line, with unoptimized gears.

It's a fat pig with an undersized engine

No i recommended the eaton because it matches up with the powerband

the Q has an incredibly high powerband, and an eaton suits it perfect. The Q doesn't need help up high, it needs help down low

Ryan: Turbo chargers have there place too. The VH's powerband is actually PERFECT for a larger turbo charger sinse it requires them a little bit to spool up. It'd be awesome to have a turbo matched up to kick in around the same time as the VVT.

The reason that you're going with the roots type charger is because you want LOWEND torque mainly. That was the whole problem with the Q

[PoorManQ45]

NOte: I would suggest that everyone remove as much weight as possible before doing any performance based mods.

[PoorManQ45]

YOu make a good pint about the money.

The supecharger will be alot cheaper then a turbo setup

[350zQ45a]

MJC: You should hitup 450ZXTT (I think that's his nick)

His name is Slim. He has a 300ZX with a VH45DE with some turbos slapped on it. The car is completely bada$$. He could probably give you alot of good info. He's the only one I know of that's slapped some hairdryers on the VH. He's also running JWT ECU I believe.

[MJC]

MJC: You should hitup 450ZXTT (I think that's his nick)

His name is Slim. He has a 300ZX with a VH45DE with some turbos slapped on it. The car is completely bada$$. He could probably give you alot of good info. He's the only one I know of that's slapped some hairdryers on the VH. He's also running JWT ECU I believe.

Thanks man. I may do that.

[350zQ45a]

That conversation was really too long. I deleted all my posts with useless info.

[AZhitman]

The same thing holds true...it seems to be limited at 350-400whp. Again, maybe I just didn't find the right cars...

My comments aren't to bash, they are to bring up OPTIONS. I don't mean any harm.

If you ever got a chance to drive a Q with 350-400rwhp, you'd see why further pursuits are worthless.

The Q is virtually undriveable (yes, undriveable) at those levels without significant suspension modifications (410 rwhp @ roughly 7 psi).

BTW, the rings aren't the weakness, it's the ring lands (and the engine peripherals) that have been (and continue to be) the bugaboo.

Back to a FRIENDLY discussion.

p.s. Welcome to NICO!

[MJC]

Interesting...do you think the ringlands could stand up to 500 engine horsepower (400whp) worth of abuse for an extended period of time?

Any idea on what the stock rods could stand up to?

This would be just the thing to show my Lexus friends what's up.

Thanks for the welcome.

[Black95Q]

In this case it "only" takes 4~6psi to make 350~400HP. Now compare that to an SR that requires 15~20psi to make that same power

Check out this SR20, 520whp at 20psi... it made 410whp at 15psi.

http://www.sr20forum.com/showthread.php?t=116821

If you ever got a chance to drive a Q with 350-400rwhp, you'd see why further pursuits are worthless.

The Q is virtually undriveable (yes, undriveable) at those levels without significant suspension modifications (410 rwhp @ roughly 7 psi).

Really? I know guys with 400hp 2500lbs fwd daily drivers....without significant suspension mods other than springs and shocks. But they are turbo so it's easy to stay out of boost.

As far as the Q, I mean if you WOT off the line then it'll be burnout city...but why not just modulate the throttle until traction is obtained?? I'd have to drive it to know for sure but 10lbs per horsepower should be very streetable unless Nissan really messed up with the drivetrain and chassis of the G50. I mean it a big heavy rwd sedan with a lsd. Bigger wheels then the laughable 15"s would be a necessity of course.

[Nismo_Freak]

The reason I brought up my earlier point of the larger M112 is not only for more power capability, but it will make the same horsepower at a lower boost and lower intake charge...thus safer for the engine. A larger compressor will flow the same amount of air at a colder intake charge, thus more dense, thus more horsepower.

This is the reason that if you put a GT28RS on an SR20, it's not going to make nearly as much power as the same engine with a GT35R at the same boost.

The problem you face with the Q's engine is that you can't cram more air into the cylinders and expect the engine to hold. You are creating too much cylinder pressure which is what cracks the ring lands, not detonation. So efficiency in this case, is a side issue.

Knowing this, keep in mind larger blowers require more power to turn. They also will produce MORE heat at lower speeds because they are not in efficiency. Compressor efficiency is defined in part by the amount of heat they produce in compression.

Thus I give you MP90 vs. MP112 (4th Gen Blowers)

MP90



MP112



Close inspection reveals exactly what I just said. The MP90 supercharger is not only more efficient (thus cooler charge), but it requires slightly less power to rotate over the usable powerband of the VH.

Hence the MP90 is better suited for the stock VH45DE engine in all regards, which we all seem to mostly be in argreement with.

The GT28RS @ 15 PSI will get outran by the GT35R @ 15 PSI because the GT35R is outflowing the smaller compressor. Flow is not the same at the same pressure for two differently sized compressors. Air temp for the two at a 2 PR are more than likely close to the same temp as most turbochargers in this size range have wide efficiency islands around the 2 PR region.

While you may say that the M90 is more than capable of 6psi (which I agree, it is), it does have limitations that will approach very quickly if trying to pass 350whp on your way to 400whp. The GM 3800 guys have been running these things non intercooled up to 11psi (so I am told) and go higher than that with one obviously. My only concern is that I have never heard of one making more than 370ish whp without nitrous. (again, it's very possible that they have, I just don't personally know of one).

11psi on a 3.8 liter would 'roughly' correspond to 9.3psi on our 4.5 liter, which is more than I'd want to run on 10.2 compression w/ 93 octane anyways, but they run this on an 8.5:1 compression motor that with an efficent compressor will gladly stand up to 17-18psi on 93 octane on a daily basis with a safe tune.

The VH45DE engine is mechanically efficient in all regards to the GM 3.8L engine. It's DOHC w/ VVT valvetrain is more efficient in the upper RPMs where peak power counts. Although engine VE tends to be limited in it's ability to produce power due to the compressor limiting absolute flow.

The kicker between the two is the Q's huge benefit of running a higher compression ratio.

If they are getting 370whp out of the blower then there is no reason a Q can't make 400whp in my mind. However the Q will need alot of dyno time to get to that point and it won't be made on an off-the-shelf JWT tune.

[MJC]

Great post. Interesting maps you posted up there, good info. Now I definitely understand where the choice of blower came from.

As for the 28RS vs the 35R, it's not necessarily about flowing more, it's about doing it more efficently. 20psi is 20psi in the engine, as you know it just means 20psi of back pressure. The 35R is making more power due to the temperature and density of the charge. If you break it down to symantics then yes it's 'flowing more air' but that, again, is due to the efficency of the larger compressor.

Which is where I was drawing my comments on the blowers from. But as you proved above, my assumptions were incorrect. That's what I was looking for ...someone that knew more about the blower to set me straight.

[elwesso]

Great post Alan, thanks a lot!!!

I have one word for everyone who thinks the Q will be "undriveable".. 2nd gear start... I have my 1990 TCU ready, and 2nd gear start will be great for taming the beast within.....

Remember what AZ is basing it off of is Rex's supercharged Q (THAT rex, not to be confused with not that rex ), which was for all intents and purposes a POS. Engine wasnt in very good shape, suspension was fubared, stock transmission (which was questionable) and so on.. I think if you did some minor things like solid rear subframe bushings (or at least poly) thatd really help... I dont see why 400HP cant be made driveable...

Alan mentioned something about additional tuning that would need to occur.... What do you think will need to be done????

I think if I attained 400HP (350RWHP) or so (give or take) id probably stop there...

[AZhitman]

Really? I know guys with 400hp 2500lbs fwd daily drivers....without significant suspension mods other than springs and shocks. But they are turbo so it's easy to stay out of boost.

As far as the Q, I mean if you WOT off the line then it'll be burnout city...but why not just modulate the throttle until traction is obtained??

You answered your own question - the Q was s/c, so it IMMEDIATELY stepped out of line, even feathering the throtte (granted, it had 1st gear start).

Also, Wes is right, the car was a POS on OEM dry-rotted tires and tired suspension.

People who start throwing around numbers upwards of 375hp have usually never driven a car putting that kind of power to the ground, and must realize that at some point, the law of diminishing returns takes over.

410 rwhp was simply too much to make the car "liveable", however, I believe it would have been perfect for a car that has been well-maintained and with proper tires. Remember, that is nearly DOUBLE the stock rwhp.

[elwesso]

Im going to give Rex a call this week and see what he can tell us... I want to hear some from him.....

[MJC]

elwesso - he probably just means extra tuning in the fact that no two cars are idential. You can have the exact same setup and the car will put down different power with different fuel necessities... I.E. the 20+ whp swing you can find on stock LS1 F-bodies of the same year. And the higher in power you go...especially adding FI, the more variables you throw into the mix.

You answered your own question - the Q was s/c, so it IMMEDIATELY stepped out of line, even feathering the throtte (granted, it had 1st gear start).

Also, Wes is right, the car was a POS on OEM dry-rotted tires and tired suspension.

People who start throwing around numbers upwards of 375hp have usually never driven a car putting that kind of power to the ground, and must realize that at some point, the law of diminishing returns takes over.

410 rwhp was simply too much to make the car "liveable", however, I believe it would have been perfect for a car that has been well-maintained and with proper tires. Remember, that is nearly DOUBLE the stock rwhp.

I understand what you're saying, and I don't know if you were partially referring to me, but I've driven cars with plenty more horsepower than that...1000ish, not that I'm a pro with that type of power yet, but I'm no stranger to 120-150mph trapping cars.

As I said before, I'm not looking for a 600whp 2 1/4 ton missle, but a nice calm and reliable 400whp would be perfect.

[Nismo_Freak]

As for the 28RS vs the 35R, it's not necessarily about flowing more, it's about doing it more efficently. 20psi is 20psi in the engine, as you know it just means 20psi of back pressure. The 35R is making more power due to the temperature and density of the charge. If you break it down to symantics then yes it's 'flowing more air' but that, again, is due to the efficency of the larger compressor.

Like I said... it increases flow.