i know most people doing forced induction turbo thier LS1's. just wondering why they don't supercharge them instead?

is it because most supercharger kits don't fit, either hit the hood, or the radiator, or do they just like turbos better?

besides the whole efficiency thing, i would think that a supercharger would be much more fun if your using the rx-7 on the street. i drove my dads SL 55 and the response was amazing. even just slowly pulling away from a stoplight, you could feel the push. i love the turbo sound, but i think a supercharger would be mad cool on an LS1 in a 7.... not that i would need it, i'm sure 400+ lb/ft is more than enough torque.

i'm sure they are many reasons people choose turbos, just wondering if anyone has done a supercharger...

laters

harrison

 

There are people running blowers on their conversions. CDK4219 here has a procharger on his LS1FD, and I've seen pictures of an LS1FC running a modified GTO procharger kit. A magnusson SC willnot fit without modifying a new hood (meaning a new custom hood, or a scoop), which is why you don't see people using them.

Personally, I don't like the whine of a supercharger (most sound like squeeky wheels to me). And I don't like the parasitic power losses, or the potential for thrown belts. The couple people I know with SCs seem to always have problems with them, so I've tended to avoid them.

Plus, I just like turbos. I like the sound, I like the "exponential pull" that they seem to generate. The only thing I don't like is the slimmer margin for error, though there's likley more of that with my LS1 than there was with my 13brew

 

With a supercharger you get boost right off idle. Trying to lauch a lightweight car with a stock LS1 is difficult enough! Turbo lag in this case is your friend and can be dialed-in with a good boost controller. The turbo will give you a bigger more efficient boost curve in the upper RPM range which is most welcome once your car has "hooked-up".


Sean

 

yea, i was thinking about that too... that our cars are really light. cool, thanks for the replies. i'm sure if i did the swap in would do some kind of forced induction, i don't really like the whine of a supercharger, but they are only certain kinds that whine right? or is it just based on the pulley you are using? if i did the swap i'd love to have a rather quiet motor, just so didn't draw attention to myself.

anyway, thanks again.

 

If I go FI somewhere down the road, I will probably go with a procharger. As much as I love turbos, these engine bays are just too cramped.

An fc on the other hand has quite a bit more room under the hood. It looks like you could almost flip the manifolds upside down and plumb it from there.

 

Hehe. If you compare to a Camaro (LS1 donor specificaly) you will see that the RX7 has some extra elbow room in some places.

Sean

 

Yeah, but I can tell you from experience that the extra elbow room isn't going to help you mount a turbo. It will let you get to the rear spark plugs and change the intake and fuel rail a little easier.

 

True!

Sean

 

I'm still torn on my future F/I setup. A mid-mounted turbo is one option, but a nice cowl with a whipple on top of the engine is quite tempting as well. I've driven high-power S/C cars for a long time, and built several (high HP is a relevant term, I'm talking ~425 HP V6s, but ~450 TQ) so I'm a big fan of the "feel"

Ah well, I'll figure it out once my wallet recovers from the swap thus far.

 

If I'd have known 8-10 months ago what I know now, I would have steered clear of a FI setup and stuck to the heads/cam/headers route, and maybe added a procharger if I got bored with it.

The turbo setup has been a complete PITA, and has cost way more than I could have anticipated. I've tried a few different setups before I settled on what I have. If I wasn't this far into it and so close to finishing I'd scrap it and go back to NA.

And I'm not sure if my wallet will "ever" recover.

 

LOL, yeah, partly why the whipple concept looks good to me. Overall a "roots" style (I know a lyshold screw is very different, but they still have the same... roots... pun intended) is very simple. Intake adapter, belt routing, bypass valve, done. And instantenous boost is always fun, if a little tough on drivetrain components. The hoods done by "rage" on the forums for his Ford swaps actually look good to me, and I'm 99% sure I can clear a whipple with one of those.

 

Like Andrew stated superchargers throw belts often and have problems with slippage... meaning less boost than you set it up for. Parasitic hp losses and pressure on the snout of the crankshaft are another downside. Head units for superchargers are $$$$ if yours lets go.... and I've heard of plenty of ProCharger units giving up the ghost prematurely.

Turbo setup is more involved .... but yields better results. The work is certainly more involved.

I would easily guess that 95% of forced induction setups in non amateur racing are turbos. I've heard the figure being actually higher.