Lets talk superchargers + gas mileage (z32)

[xXxRocker5150]

Alright guys, well as much as I love my z31, today when I was driving to the train station to drop my mom off, she says to me "so if you had the chance, would you rather have a 90's+ model z? or yours???" and I said to her... "you know, I really don't know." Well when my mom says this kinda stuff, it usually means that she'd get it for me... AKA as a high school grad. present (if I get good grades)....

Therefore, my question is this; do they make supercharger kits for the z32s or not??? If not, how hard would it be to make a kit for it????

My question about gas mileage is this; what kinda gas mileage do you guys get (or did you guys get when you were stock)??? Right now I average about 17 or 18 in the city and anywhere from 25+ on the highway. Thanks for looking!

[k3smostwanted]

there are no supercharger kits for the 300zx because it is offered with Twin Turbos. most people just stick with the turbos because they are more efficient and the engine is already built for it.

as for gas mileage, with my N/A i got about 17-18 mpg city and a little over 20 on the highway. but keep in mind...i never went under 90mph on the highway.

[DeleriousZ]

why in the hell would you want a supercharger?

[xXxRocker5150]

I like instant boost... but I was also looking for an alternative to TTing an n/a becuase I wanted a 2+2 with forced induction, and it just seems like the TT swap would be a btich

[DeleriousZ]

would probably be easier than trying to get a crazy custom twin supercharger deal to work... and it'd probably be even harder to get a single one to work (probably have to steal wes's single plenum design )

[1viadrft]

Originally Posted by xXxRocker5150

I like instant boost... but I was also looking for an alternative to TTing an n/a becuase I wanted a 2+2 with forced induction, and it just seems like the TT swap would be a btich

You are better off TT'ing the NA or just buying a TT Z32... Supercharger? You won't be happy with it even if you could afford it. A few people have done it and the HP gains are not great at all... think nearly stock TT power. You'll have to worry about lowering compression since the NA is not meant for boost. That means new pistons. Totally not worth it IMO. If you want boost... buy a TT. If you want a TT 2+2? Talk to Jason about that 'cus that crazy son'bitch is doing it. I wouldn't mind doing it myself but my current situation will not allow for that much down-time. Hell... or you can be a crazy son'bitch like me and make an 11-second VG30DE powered Z32. That may not be the most efficient way though either though.

[ExTrEmEDrIfT]

pfft i dont care about boost at this moment i just got a new job and gas prices suck ass so much its getting ridiculous

[1viadrft]

^ Tell me about it! ^

[xXxRocker5150]

hmm, well in that case, if I were to swap in a TT engine, are there any other parts I'd need to change along with the engine?

EDIT: nvr mind, I read jason's TT swap, lol maybe I should just say forget it and just get a TT... do the 2+2's really have that much more cargo room/space????

[k3smostwanted]

Originally Posted by xXxRocker5150

hmm, well in that case, if I were to swap in a TT engine, are there any other parts I'd need to change along with the engine?

EDIT: nvr mind, I read jason's TT swap, lol maybe I should just say forget it and just get a TT... do the 2+2's really have that much more cargo room/space????

my backseat makes a nice bookshelf for when i attend school. if you absolutely have to give somebody a ride, it is doable...but you better hope they are a petite female.

do yourself a favor and buy a TT...it would probably be easier to incorporate soem more space out of the 2-seater than swapping to a Twin Turbo. and yes you will need ALOT more parts besides the engine...easiest way to do it is to buy a front clip. if you decide to do a swap, you will thank yourself later. trust me...

[apostrophe28]

if you know the right people you could always go for the custom single turbo job

[1viadrft]

Fabrication cost's for a single turbo would equal the same for a 800rwhp+ TT... why bother with a single?

[xXxRocker5150]

I just thought of somthing guys... I know in Europe they have left hand drive z's (the fairladys)... and aren't those turbo models 2+2s??????

How much would it cost to get a left hand drive model into the US???? Not a JDM one, but just a Euro one.

[DeleriousZ]

too much... unless you're importing a car from canada it will cost you very large amounts of money to import from anywhere else... you might as well import a skyline for the price you'd be paying

[longlivetheZ]

Originally Posted by DeleriousZ

why in the hell would you want a supercharger?

: Amen, brother *in a really red-neckish voice*.

Here ya go...here's all you wanna know regarding Turbo vs S/C and S/C gas mileage is even talked about quite a bit in there. All in all, S/Cs blow...no pun intended. If you can read all of that and still want an S/C, then go for it...

Here's the bulk of what you care about...it's all good reading, though:

Originally Posted by Exerpt from above link.

Online Editor’s note: The November ’01 issue of Hot Rod featured an extraordinary twin-turbo ’66 Mustang owned by Bill Watson, a jet engineer with Garrett/Honeywell. He generously supplied us with way more detail on his project car that we could fit in that issue, so we decided to include this question-and-answer interview that explains why he considers turbocharging superior to either supercharging or stroking an engine for more power. You may not agree with all of his points, but he knows his stuff. (After all, his Fastback runs in the 11s on—get this—SlimFast 215-section tires!) Blower buffs are invited to email us their alternative views on the best way to obtain boost.

Q: Other than the fact that the company you work for makes turbos, why go the turbo route? Why not use a supercharger or build a stroker? Are turbos simply the most efficient way to go?

A:There are four main reasons why I think turbos are superior to a blower, but of course I can’t argue that the supercharger isn’t easier. It is. I can appreciate why supercharger kits are more popular for the bolt-on crowd. But here are the reasons that I prefer turbos:


1) Turbos always will outperform supercharged cars when it comes to power production. It’s simple—you don’t have to spend (for instance) 70 crankshaft horsepower to drive compressors by taking engine horsepower right back off the crank. True, you back-pressure the engine on a turbo car, but much of the compressor horsepower comes from heat—and that is "free." The bottom line is that you don’t sap as much power out of the engine to get your pressurized air.

2) Easily adjustable boost! It’s a breeze to set up a knob inside the passenger compartment to adjust the wastegate setting up or down. When I drive in the mountains, I can raise boost to get back the power lost at higher altitudes. On the other hand, if I buy cheap gas I can turn it down, or change boost to compensate for summer or winter air temperatures (or for that matter, morning or evening temps too!). With a blower car you have to change pulleys—not that hard, mind you, but very few people are going to change pulleys as they’re climbing mountains, or at a gas station after buying a tank of cheap gas.

3) Midrange torque!! Boost vs. rpm is far superior on a turbo car. With a belt-driven centrifugal blower, you have to choose a pulley size so you won’t overboost at redline. But that means that at every rpm below that, you aren’t running as much boost as you can. The nature of centrifugal blowers is parabolic, meaning at half the redline rpm, you make less than half of the boost. So on a typical 5.0L, you might only make 3 psi of boost at 3,000 rpm, where a turbo car can easily be on the wastegate for 11 psi. That’s why I make 550 lb-ft at 3,000 rpm. Hey, if you cut my boost to 3 psi at 3,000, my torque would be down to 340—that’s 200 lb-ft less! To me, the best way to optimize a belt-driven centrifugal blower car would be to loosen the torque converter. Then you can hit the gas, immediately be at 4,000 rpm for example, make boost in an instant, and have a bolt-on car that just hauls. The only downside there is the economy will take a hit unless you can design in a lockup converter when you want to just cruise down the freeway. The turbo doesn’t have any of these compromises.

4) Finally, turbos run proportional to demand. What I’m getting at is that compressor speed is dependent on airflow, which comes from two main variables: engine rpm and throttle position, if you will. Now, a belt-driven blower car’s compressor speed is dependent on only one variable: rpm. So why care? Because when you’re just maintaining speed on flat and level ground, trying to make some mileage, a turbo car’s compressors are going very slowly and hence don’t increase pressure before the throttle body. But a belt-driven blower car has no idea what the throttle position is; the compressor is simply geared to the crankshaft, so it’s spinning much faster and making, say 2 psi in our example here. (And if it’s a Roots-type blower, it’s making 6, 8, or even 10 psi!)

So what do you do? You have to back out of the throttle even more. That means throttling losses are up (bad for mileage), and you’re pumping hot compressed air through your intercooler all day if you have one, and you’re using crankshaft horsepower to compress the air—then throttling it back anyway! At least put the throttle body before a blower; you can see why positive displacement (Roots or screw compressors) blowers have the throttle plate before them to avoid this problem. Then it’s much more of a non-issue.

You’ve also asked why I didn’t go to more cubic inches. Of course that works, but as you note the mileage wouldn’t be as good, plus I’d still have to build a 7000rpm motor to make this kind of power on something under 400 cubes. Then that requires all the money for rpm-related hardware to accommodate moving the operating range up, which I have spent zero dollars on. The turbo approach was different, in the sense that you spend the same money but on different hardware. I’ve done the cam/carb/intake/heads/headers/loose converter thing before. It was fun, but this time I wanted something that was a real sleeper until you lean on it.

I love turbos!