All the time I've heard that blowers/superchargers are bad for the engine of your car.. how true is this?? how big is a safe one to put in without ****ing up your car?

------------------
Hey feel free to chat with me on AOL IM if you wanna.. Darkhal2000! Also if you wanna join my webring gimmie a yell at my email addy. I'm always looking for third gen's to add.
My site, http://www.personal.psu.edu/users/j/m/jmj211/index.htm

 

It depends on many things. Type of engine, condition of internal components, mileage on car, fuel system used, etc.. It is hard to predict what is "bad" for an engine. Obviously if you throw a 300hp dry nitrous kit on a stock 305 you're looking for trouble. Same goes for bolting an XX-trim Vortech on your ride.

------------------
1989 T/A, 400" CNC Bow-Tie tall-deck, JE 8.5:1, Scat H-beam 6" rods, Scat 4340 crank, Crower roller cam, AFR heads, Accel Pro-Ram intake, 1200-cfm t/b, DFI, 72# inj., S/X fuel system, Hahn Racecraft T76 single turbosystem, NOS 150-hp dry fogger, TH400 w/GV overdrive, Dana 44 w/3.54's, Baer Track brakes, 18X9.5 wheels, P275/35ZR18 Nittos, Spohn suspension, S/T springs, KYB AGX shocks/struts, Corbeau Targa RS seats, TeamTech 5-point harnesses, Sparco steering wheel, MacEwen white gauge overlays, Phantom gauges/tach, B&M Pro Stick w/carbon-fiber ****, REAL carbon-fiber dash/console kit (don't ask), S&W 8-point rollbar, Lonza aluminum pedal covers, Pioneer/Boston Acoustics stereo system, filled side markers, Audi clear fender marker lights, custom clear front turn signals, custom clear taillights, IMSA-style cowl hood (don't ask), custom medium Intense Blue pearl paint, tinted glass. Whew!

Best ET w/383" S-trim: 10.796 @ 125.8 mph
Best ET w/400" turbo, nitrous: Summer 2001

Member of Midwest F-Body Association www.mfba.org

 

I think "bad" is the wrong way to describe it. General Motors designs and builds our cars with certain requirements. If they build a 250 hp engine, the parts are as cheap as possible to reliably take the stress of 250 hp. If you modify the engine to 300 hp, there is no doubt that it will still last. However, when you start adding lots more power, parts break. You can't expect engine parts built to take 250 hp to last forever at 450 hp. The question isn't of "how bad" its more of "how much can I get away with?". A stockish engine with more hp will never be as reliable as it was with less hp. It might be 95% as reliable, and thats the game everyone with stock internals is playing.

Andris, with a stock internal L98 and twin turbos

 

most superchargers put tremendous strain on the nose of the crankshaft (depending on belt tensioning system). This can quickly wear out the mains and create a lot of play in the crankshaft.
Depending on how much boost pressure you run, you also have to increase your valvespring pressure to ensure they maintain proper seating pressure to seal. This is not a big problem but can add wear.
With a supercharger or any kind of boost you need a very good crankcase evac system. Otherwise excessive pressure will load down your oil pump dropping oil pressure and sometimes causing the pump to fail.