1/4 mile is fun but I would like to try turning some corners, both left and right, but would like to add a little some'n some'n to my power and want to know which power adder you guys think is better for road racing, turbo or supercharger?

Let the debate begin!

 

I would think a supercharger would fit better.

Almost (repeat twice) instant response

Of course if you kept the rpms up a little, a quick spooling turbo may work

But i dont have either so, grain of salt

 

Have you attend or watched any road racing: SCCA, Rolex Sports Cars, American Lemans,Indycar/Cart,F1 etc. . I 've seen hundreds of turbocharged cars. But do not recall many blown cars except for drag racing.

 

how about a whipplle

 

There is a difference between turbos and supers in that a super is going to have instant power and a turbo could take some time to spool known as turbo lag. With a supercharger you're sacrificing a little power to have instant power.

With turbos becoming more and more advanced and new technology, turbo lag can be greatly diminished - but with all most new technology its going to cost more.

I'd choose a system based on reliability and bang for your buck. Lets say you save $600 dollars on whichever system you go with, you can use that extra money for other "go fast" parts. For cornering the best performance upgrade is going to be a good set of tires, likewise they will help tremendously for straightline racing aswell. If its cornering your really after I'd suggest upgrading your suspension. Depending on how technical/curvy a coarse or even open road you are on, a car that can take a corner at 10 mph faster even with 150 less hp is going to be faster.

I'd personally go with a supercharger, Its much simpler so you have less things to go wrong, and if your going to be going on and off the throttle a lot your probally going to want the the instant power. It will be a little easier to drive aswell cause your always going to have the same amount of power at a certain RPM/Throttle position, versus a turbo will depend on 3 factors: RPM/Throttle position/current turbo speed. A supercharger always spins in direct proportion to engine speed. If your car is an auto i would lean towards a supercharger, cause if you take a turn, cut throttle and the trans shifts to the next gear, you just lost all your turbo pressure versus a turbo w/ a standard your going to use the engine to slow down the car some and thats going to keep your rpm's up and turbo mostly spooled coming out of the turn.

But like I previously said - choose on bang for the buck and reliability (although a smart consumer should always consider reliability as part of bang for the buck).

 

how about a lil Sneaky Pete. Just enough to get past the leader on the home stretch. Could make all the difference between winning and "also ran".

 

Not all superchargers are instant boost. My Vortech supercharger is a centrifugal design and it has "lag" similar to what you would see with a turbocharger. I doubt nitrous would be allowed in any type of racing leagues.

Anyway, to answer the original question I would say none of the above. Its definately possible and alot of other people do it depending on the car and type of roadracing, but I would recommend you stick with a N/A setup. The SBC engine can be built to put down some pretty impressive power numbers N/A, probably as much as you would need. N/A setup will be very reliable, responsive, and consistent as far as the powerband. Throttle control is very important for roadracing and if your powerband is very steep or peaky it makes throttle control alot harder. You wouldnt want to be coming out of a turn at the limits of traction and then have boost hit and upset the traction. You also have to keep throttle response in mind, when you need the power you need it. I say drop the $$ into the heads and cam, and even the bottom end if you can afford it. As an added plus you should get aluminum heads and drop some weight off the front of the car to help the weight distribution. Also, definately go with a manual tranny, it makes roadracing much much more fun and technical (the things you can do with the clutch versus having an auto).

 

Maybe it's just me, but i think a lot of peopel forget that the TPI system loses itself about 4500rpms. Isn't that when the turbos start to really pick up, when a supercharged starts to drop off around there too? I would say match you intake system to the power adder. A TPI system, even if it is somewhat modified would probably be best matched to a supercharger, and you are goign to be changing gears and banging through the corners. This is where the TPI sytem shines the best. I'd say go with a supercharger. Once again, jsut my

Brett

 

A turbo that doesnt kick in until 4500rpm is just a badly miss-matched combo. I have a relativly largish turbo that I was told was going to come on too late, but it starts to do its thing at about 2800rpm which is fine.

Although I think on a very technical track, spending money on suspension and brakes will give you faster lap times.

 

N/A what fun is that?

Running a HSR for intake right now, looking at a 383 with power adder, have a 700r4 but a 5 or 6 speed is not out of the question.

 

A properly sized turbo will not have any boost lag at road racing rpms, and definitely not any more than a supercharger at the same low rpms. Most V8 turbo guys are already at 10+ psi by 3000 rpms, where the superchargers are just starting to produce boost.

In any case - If you're serious about road racing, I would abandon forced induction completely. Get an LS1 with heads, cam, and longtubes, and call it a day. A forced induction engine will need an air:air intercooler (40+ lbs right on the nose of the car), much larger engine clearances, bigger (read heavier again) fuel systems, etc. Sure you can make lots of power, but the reliability of a simple NA engine is very tough to achieve with a turbo/supercharger. Figure on spending many thousands more to get everything as reliable as NA. Do you want to be wrenching, or racing? That being said, seat time is much more important than HP. If you can save 10 seconds a lap by being a better driver, just think what more HP and lighter weight will do later on in the game...

 

Lets go back to the beginning.. Without knowing what type of roadracing your talking about. The first item to determine would be what class and whats allowed in the rules . Otherwise this is one big neverending circle .

 

depends on the supercharger… my brother’s car shows full boost in the data logs at any rpm within a frame or 2 of going WOT. Positive displacement blowers are cool that way

would you like to tell us how you know

I do agree with you 100%, if I was going to set out and build a road race car I’d be looking at the nascar style small blocks… something strong, reliable and high strung. In the long run this will be a much better/cheaper setup and much less hassle at the track

 

I guess I should have rephrased it to be "centrifugal superchargers" need RPMS. In any case, this month's Machine Design magazine has a great article on the C6R development.


C6R article

They run through two 31.5mm restrictors at 590 hp, and I also found interesting: Geez - That sounds very similar to TPI! In any case, if you're just starting out getting experience on track (High Performance Driving Schools, Open Track Days, etc), don't bother getting the latest, greatest, fastest whatever. Just grab an instructor and get as much experience as possible. Are you thinking of doing wheel to wheel racing? If so - then it's even more important to get experience before you're on-track with 15 other nuts