supercharged sentra

[Twilight sentra tuner]

question. what do u guys think about putting a centrifugal supercharger on a sentra, doesn't matter what engine u got. opinions???? Cause i'm thinkin a/b it.

[Twilight sentra tuner]

http://www.turbomagazine.com/t...art_1/#.

on a spec-v. hopefully the picture shows. just scroll down and you'll see it. what do u think?

[nametakennow]

I've seen videos of the supercharged Spec. It's interesting, but IMO not worth it. For the money it takes (given that, at this point, no one really makes a kit) you might as well shoot for turbo.

[Twilight sentra tuner]

i wouldn't imagine it would cost too much besides the price of the supercharger. with a turbo u gotta buy a turbo manifold, blow off valve, wastegate, extra exhaust piping, the turbo itself with the intercooler piping and the intercooler and so on and so forth. supercharger ( i'd imagine) would be cheaper. but i haven't looked up prices though for the CS itself. i'd just try to find one that would manage to fit. i could take out the a/c compressor. that would make room. and i don't use the damn thing anyway so its not a loss for me at least.

[b15chik]

it isn't really cheaper, traction sucks, and it sounds like a whiney airplane

[VMPhil]

S/C is just as expensive is turbo and depending on your setup Turbo would yield better results.

[nametakennow]

Superchargers for pretty much any car are about the same cost as a turbo setup. A Sentra would be no exception. You still have to have all the intake piping and everything, you SHOULD still use an IC, albeit that it can be considerably smaller, you still need engine management/fuel upgrades, etc, and, really, if you run a stock exhaust mani/midpipe/catback with a supercharger you're an idiot because you're not giving all that air anywhere to go. You also need a custom belt setup (assuming it's belt-driven).

[Twilight sentra tuner]

yeah i was doin some research and nothing that great. and by the way the stock exhaust will be swapped out for a high flow setup. the backpressure would kill. i'd definitely be doin an engine management unit, IC,and probably get a walbro fuel pump, upgraded injectors, aftermarket fuel rail along with a FPR. i know all the stuff i need to do before the hypothetical installation. just curious mainly on the comparison and cost.

[NSR_s30]

If you're looking for forced induction, I think your best bet would be a turbo.

[Twilight sentra tuner]

but thats the thing. i want to do something different. everyone is runnin a turbo on the se and spec's. ( dont get me wrong, i love turbochargers. their the best example of recycling and they kick *** with lots of boost.) i want to try the supercharger though. it hasn't been done much. i don't think ever for a qg. it would be interesting tosee results and hopefully not end fatal.

thank you guys for ur opinions and inputs.

[nametakennow]

We're just saying that, purely from a cost standpoint, it has nothing over turbocharging. If your goal is more instantaneous power, then, arguably, supercharging is more effective than even a small turbo.

Personally, I take issue with adding MORE belt/crank-driven equipment to take away rotational energy from my crank when I could just spool up with exhaust gases that are on the way out anyway.

[Twilight sentra tuner]

that is one thing a/b the turbo. no rotation off the crank. for the supercharger what a/b an underdrive pulley to relieve some of the stress? it would be less rotational mass. drop out the a/c compressor too. even better. that is if u don't need it. me? windows down all the way. lowers the car's center of gravity. i culd live without the luxury.

[nametakennow]

Lowered windows actually hurts performance/efficiency too thanks to additional drag. I used to be hardcore about just windows down, but nowadays, especially with GA's humid summers, there are times where AC is really the only tolerable way to go.

Anyway, underdrive pulley and AC removal would help, sure, but why compensate for the supercharger's effects when you could turbo and avoid them altogether?

In all honesty, a supercharger's stress (especially if it uses ball-bearings) on the engine isn't really squat compared to the gains if you're running a decent pressure. I just think the turbo's efficiency of using waste to generate power makes more sense.

[Twilight sentra tuner]

well the underdrive pulley decreases rotational mass and dropping the a/c does too but the main reason i'll lose the a/c is because of weight. its coming out regardless of what i do. the a/c loss won't compensate the supercharger, its just less stress off the crank. i want to put a UR crank pulley on the engine too.

believe me we get some hot ones up here too. i just learn to handle it.

[nametakennow]

I don't doubt that VA can be vicious as well, I just age more quickly than my years and, therefore, have lost my tolerance for weather already.

Anyway, I get that you're looking at taking out stress from the crank, but adding the supercharger on basically undoes all/some of that to put you back near zero net loss in rotational mass. Though, if you get deep into those arguments, many people will claim that the changes will mess with the crank balancing and eventually destroy your engine. I tend to side with those who say that since Nissan uses internal balancing, the pulley really isn't a harmonic of any kind and, therefore, a lighter one won't hurt.

The best place to drop rotational mass is at the wheels.

[Twilight sentra tuner]

haha u made a funny

basically yea. i'm tryin to take the stress off the crank. use the crank pulley for less rotational mass, drop the a/c which decreases it some more( and also for the weight) and use an underdrive pulley for the supercharger. the underdrive would be smaller than the pulley for the a/c so rotational mass would go down right?

i just recently put on a set of wheels. 17" 5 spoke motegi racing wheels wrapped in sumitomo all season performance sprint tires. they're lighter than the factory wheels so one up!

[nametakennow]

I think you're missing my point.

Before I get to that, though, I must admit that I have no idea what those Motegi's weigh off the top of my head. I know that my stock wheels weighed in at ~22-23lbs a piece, and my 17X7's are 19lbs. Of course, many will argue that the distribution of the mass factors in since a larger wheel spaces the mass further away from the hub and, therefore, causes more stress per lb. My stockers were 16in, so I figure that since 4lb/23lb is larger than 1in/16in, I still made progress, though, really, I wish I could find some 16X7.5s. I'd have to dig up my notes from physics class to figure out whether or not my quickie math actually works out. All the same, I'll probably pick up the NISMO 17X7.5s that weigh in at 16 or 17lbs, if I recall, in the next year or so along with slightly wider and stickier tires for even better performance and less of a "steal me!" look.

Anyway, back to your engine.

Yes, an underdriven pulley on the supercharger and AC removal and/or an underdriven pulley set will mean less rotational stress on your crank than stock. However, my point is that simply adding the supercharger is going to be more stress than if you removed the AC, used an underdriven pulley set (set being crank and water pump pullies... they may have a power-steering pump pulley as well), and used a turbocharger instead of a supercharger. I doubt that reduction of mass would entirely compensate for the turbo lag, but I can't be sure. However, the increase in midrange and top end would make up for it with ease, IMO.

However, I hope lag wouldn't be much of an issue in turbo land since I'm assuming that you wouldn't use anything bigger than a Garrett T25 or Turbonetics T3. If you had big bucks, you could use Garrett's T25/28 hybrid and get the quickness-of-spool of a T25 and the top end of a T28. Of course, if you had big bucks, I'd question why you're working on a Sentra this much anyway, particularly if it's your only car. That is unless this is an exercise in showing what can be done just for fun.

[Twilight sentra tuner]

how would adding the supercharger be more stress by taking bigger components out( a/c)?

i'm still looking at the turbos and the t25 would be perfect for me. i wouldn't have to beef up the pistons but its just the process of finding all the other parts to make it work. and the price...

i'm working on the car not for speed or attention, but mainly out of curiousity. i want this car to be all that it can be( not relating to the army). basically i want to show people that anything can be done with determination. that and also its for my thrill of what this car can ( and i mean can) do with a little time and effort.

[nametakennow]

IMO, there are plenty of examples of determination out there. However, automotive philosophy, if you will, is completely individual, so have at it.

Your plan is:Crank - ac, etc. + supercharger running off crank

That is less efficient than:Crank - ac, etc. with a turbocharger hanging off the manifold.

I'm not saying that the supercharger itself will be MORE stress than the other components. With your plan there should still be a reduction in rotational mass off of the crank. However, there will still be more rotational mass connected the the crank than if you still removed those components, but used a turbo instead.

[Twilight sentra tuner]

i got ya . makes sense now. i am still debating the turbo. its not a dead possibility.

as u said it is a/b making this car me. turbo is nice. but the SC sounds pretty nice too to me (in my opinion ) either one of them will show a bigger significance to the cars power. but i am lookin for a faster takeoff (SC).