Turbo vs. blower debate w/in

[Lord_Verminaard]

You make some good points Mike. It seems that a lot of the people that post opinions on turbo cars have never driven one and go by what the magazines say. (makes me wonder if the magazines have even driven them!!) Modern Turbo Diesels are even more amazing. There's just something not right about a 7400 lb truck being able to go that fast. [img]smile.gif[/img] So I am biased about turbos, but for my car, the supercharger route looks better and better, just for the reasons of overall cost and ease of installation. You could find a used turbo for cheap, but then need to rebuild it, then fabricate (or pay someone to do it) manifolds which arent avaliable to the aftermarket, run extra cooling and oil lines, lots of plumbing, etc... and the cost adds up. I would REALLY like a turbo 3.8 running about 12 psi of boost for a nice and fun daily driver. But after all that, slapping on a charger and FMU and being done with it sounds nice too. The beauty of the SC install, is that if you get all of the components together and get everything ready, you can do the install in a day if you are mechanically inclined. A turbo setup would take a few days and cause a "car down" situation while manifolds are being fabbed, etc... So there are lots of pro's and con's. It depends on facilities avaliable, people you know, but in the end, MONEY. [img]smile.gif[/img]

Hell, at this point, I'll take forced induction any way I can get it...

Brendan
2000 L36 M49

[mattsv6]

you can build boost in a stick car. jsut need a 2step! [img]graemlins/burnout.gif[/img]

[Tiago]

<blockquote>quote:</font><hr>Originally posted by mattsv6:
you can build boost in a stick car. jsut need a 2step! [img]graemlins/burnout.gif[/img] <hr></blockquote>

I love mine :D

[mattsv6]

\m/

[FlybyChevy]

Yikes...you guys need to keep the topic to turbo Vs Supercharger only, all this other stuff is only going to complicate things.

Okay first things first...

1. HEAT

This is the most likely the biggest issue with FI that can be controlled somewhat by picking the right tool for your car.

What you want to know about first is adabadic efficency...just look that up. At 100% efficency you will still generate excess heat due to compressing gas, this is apart of the ideal gas law. The "in/efficency" of your turbo/super will further increase that. By nature turbos rule here, it has been proven over and over...without inroducing any other factors at equal boost the intake charge of a turbo will be cooler. I have seen some arguement on screw type superchargers being more efficent than centri but I'll assume those are pretty close to each other. The Roots design is the least efficent.

Now we have heat soak issues. Both turbo/supers will have issues with heat building up after boosting for a long time, turbos are at a disadvantage here, along with the hard to intercool and inefficent roots (which may be worse than turbos). Most people don't bother worrying about this because they give plently of cool down/ice time between run/races. It really is only a issue when boosting for extended periods of time. Even then each system can be properly designed and used.

2. Parasitic loss

Turbos aren't driven by the crank but do create a block in the exhaust flow of your high powered engine. Exhaust backpressure is said to be around 2x your intake pressure and your engine has to overcome that thus robbing power. This can be solved somewhat by larger turbos basicly and is part of the process of picking the right turbo with the aid of experts/research.

Supers are driven by the crank and takes HP to turn. The more you compress the gas, the more you HP you'll need to do it. Supers also have exhaust flow restrictions but to a lesser extent due to being able to use large/open headers.

There's more-----------------I'll get to that later I guess. Sorry for any errors it's late.

[MrCoffee]

ok this is going to come down to application
I have a friend that has a supercharged miata. He has an acquantence at the local autocrosses with the same type of miata, only turbo charged. About the same boost number, sc miata puts down 155hp at the wheels. Not too bad for a stock 90hp car. In autoX events sc runs better (they've switched drivers). The turbo lags out of turns and off the line, which is where you need top boost faster.
BUT in a street race turbo kills supercharger.
both have about the same suspension mods done. I said they have about the same boost, I think the turbo runs 2psi higher. Both intercooled. My friend said that if he could do it all over again, he'd of gotten the turbo kit for his car.