^^ Grammar Police

The world of Turbo Vs. Supercharger is sometimes tough to realize....the truth is...when making power there are many ways to apply it. Some engines are low reving torque monsters and some rev to infinity....some cars are driven in varying situations...others live in a narrow powerband....and the same goes for turbos and superchargers...some compressors make very little boost....but move enough air to fill a football stadium in 10 seconds....lol...others can push air into 7x atmospheres....Diesel engines are a prime example of this use. Some pulling trucks make 100+psi of boost and turn 3500rpm max...LOL...insane!....and they use compound compressors to achieve these elevated pressures. On the other hand a Top Fuel motor's blower runs into the 45psi range but the motor is getting to 8500rpm...both extreme examples of each type of compressor...but the Turbo is applied to achieve ultra high boost compared to the supercharger....and the parasitics at these levels can be astonishing....with the Top Fuel motor taking a 900hp hit to spin its "Iron Lung" ....

.....on the lesser more realistic and practical end of the spectrum, there are some interesting qualities for each as well. With a smaller compressor on board...the turbo can achieve efficiency quickly with little or no lag noticed...but will quickly expose its limits as the motor swallows the air on its way down the track...which can be tolerable in less power demanding scenarios...the Supercharger will continue to build power in a linear fashion directly proportional to engine speed. This can be great for on/off throttle events....but believe it or not...the smaller Turbo will develop more low-end power with Load present. There is a fine line in finding the sweet spot for your individual needs...but careful analysis of your vehicles purpose/needs could prevent you from choosing the wrong avenue to follow.... either way...positive pressure is positively fun!

-Jack

This is a fantastic writeup, although it is a bit on the length(y) side.

Would you like some help with the abridged version? :D

-Clay

I wouldn't call it "length(y)". I'd call it thorough. ;)

Nice work. One question that you may or may not know the answer to--are the Stillen supercharger performance numbers for a Stage I or II?

+ Rep! Great insight!

Thanks for the write-up on F/I.... I read it over and over (yea, I'm a noobs...). I learned a lot.

Much Thanks, again.

This all sounds pretty incredible. 332 horsepower it more than plenty of horsepower for me. And to think that it is all naturally aspirated to insure longevity. But hey, it's a free country. Different strokes for different folks.

In my humble opinion as long as it's not the little boy racer graphics or skater stickers on the paint job then it is all good. :tup:

Haven't there been issues with some of the sleeved DE engines??? What if any drawbacks are there to a sleeved engine??

sleeving an engine can cause problems if they aren't taken care of properly. If the machinist that modifies the block doesn't hold his tolerances correctly there can be misalignment between the pistons and the crank, in the case of the darton sleeves, the cylinders may actually move around if it isn't machined correctly, the head may have trouble sealing, the difference in heat dissipation can cause hotspots to form because the iron sleeve won't shed heat like the aluminum block would have, and if you are using a forged aluminum piston in an iron sleeve but aren't running enough clearance the piston can out-expand the cylinder and seize it's self tight in the block (you have to pretend the whole block is iron and run appropriate clearances). So basically if you fork out the cash and have the block sleeved correctly by a reputable shop that has done it before and they don't make any mistakes then you're good assuming the sleeve was designed to work in the block, and dissipate heat correctly.

Think of it this way to my knowledge every single commercial semi truck has a sleeved block and they run for over 300,000 miles with over 20:1 compression ratio's often making well over a 1000 ft/lbs of torque.

turbo charger or super charger
 

The other guys didn't answer you correctly.

What makes OEM companies choose a turbo design or supercharger design for a specific car... Personally I think it solely depends on what group of consumers the car is for. If the car is for sports enthusiasts who will likely play with the engine, go for turbo. If the car is for upmarket buyers who aren't likely to alter their engines, such AMG MB's, then supercharger is the way to go. We can talk about engine longevity and which platform is responsive or more efficient and all that, but at the end it is the consumer base that the designers will think about. So, a supercharged GT-R or Z would be a hard-sell, a disaster to quarterly reports.

We know that a N/A or a turbo-charged engine design is easy to fiddle with when we try to squeeze more power out from it, and there's a lot of freedom in equipment choices and 'potential of power gains' with stock design, which are not the case with super-charged design.

So, the early 90's we saw Supra, 300ZX, 3000GT, Skyline R33, all were turbo-charged design (also offered in N/A), and those great platforms were easy to go upwards of 400+whp with "stock" turbos. (That's a nice figure back in the 90's)

Based on earlier experiences, car companies knew that owners of these cars WILL modify these 280PS crank horse power cars. So turbo-charge was the only way to go, because they didn't want to make larger than 3 liter engine, and to get that power they must go FI, while in the meantime provide a simple route, with a lot of freedom in engine modification.

A factory supercharged Supra or Z design might have been chaotic, because without changing the whole supercharger system there's very little room of improvement from factory design (only smaller pulleys with ecu reflash result in small gains of power).

Now that's my simple opinion, and one thing I can't understand is that it seems to me Chevy's small block v8's crowd prefers supercharger. I personally think that is probably due to tradition and culture.

no see the reasoning behind it is the power characteristic they desire from the motor. US cars use positive displacement superchargers on the v8s because people that buy a v8 here in the US like the way v8's snap, it's all about low end, high torque grunt that is driveable and acts just like a bigger motor. Most foreign import turbo cars have turbos because the people that buy them like the power coming on and feeling like it's going to keep going forever. highend track cars tend to use superchargers because of the same driveability reasons especially so in track duty vehicles because a supercharged car is much more controllable in a corner where as turbo cars have to worry about when the turbo's will begin spooling spinning the rear out. Superchargers aren't found on most import vehicles for another reason and that is the displacement tax and fuel economy regulations. Plain and simple a turbo is more fuel efficient, so if you are trying to up the power without having to levy a higher vehicle tax class a turbo is a better way to go. Of course when your talking about AMG Merc's do you think a guy that can buy an $80,000 car gives a rats @$$ if he has to pay 1000 a year more because it guzzles fuel? they want driveabillitiy and power they can take to the track, not an unrefined rocket that hits 3200 and takes off like it has a mind of it's own.

Edit: OEM's could careless about people who mod their cars as the percentage of owners is low, it leads to higher warranty costs, and proof enough of that is that they keep making the ecu's ever harder to crack and their proud of it. not to mention that in most places modifications like upping a cars boost is illegal if not in a legal grey area. They have divisions like GMPerformance parts, Nismo, TRD, Ford Racing, to take care of the users that do feel like modifiying their cars so in initial design there is little to no consideration to that point. Look at the oil cooler issue with nissan, the car is equipped with big brakes and a track minded transmission, and 332hp, it gives the image of a real track car which is what sells cars. Then you find out that they don't really care wether you track it or not because most people won't, so it doesn't matter to them if the brakes fade right away, or the engine over heats (making you look like a B*tch on track) they will just say it wasn't intended to be used that way, even if they market the car differently.

How much power can the automatic transmission on the 2011 370z handle?

well a few guys have blown them up rompin around the 400 mark for a while think GTM is starting to do some work on it but they busy as hell, stage2 supercharger, gtr manifold kit, white dragon, vvel tuning, and regular shop business all at once over there

I believe the Stillen SC is sentrifugal not a roots type.

his information on the kits is only applicable to the 350z engines and the stillen 350z kit was roots. the 370 kit is a vortech centrifugal