Tuner Eddy

I have a friend selling two vortech superchargers and i'm thinking of picking one up for my 2000 si.

My current setup is:

Eagle Rods
9:1 pistons
Gsr cams
ITR valves, springs, retainers
Ported and Polished intake mani

So I'm thinking of picking up one of these superchargers since i could get one for dirt. I know all about the Vortech powerband and all, but the fact that some of the vortech cars i've seen are laying down 275-300 hp, and still running 14.0-14.5 1/4 mile times, that just doesnt impress me enough to want to run this setup.

Do not turn this into a jrsc or turbo debate, because i'm just asking questions on the vortech setup.

So my questions are, why are these cars making so much hp and still running slow 1/4 times? And will a meth/or water injection along with a front mount helped keep the air alot cooler?

Any input on the vortech, or opinions, etc. is welcome, i can take it.

thanks in advance fella's.

--Ryan

Tuner Eddy

bump

SovXietday

Probably spinning like crazy with shitty launches? Honestly I'd need to see a timeslip to tell you why they're running slow times. The drag strip just isn't one of those places where you can make X power and run X time.

Not a fan of the Vortech supercharger. If you really want to supercharge, talk to the procharger guys. Otherwise I'd just go turbo and make good power that way.

A.E Motoring

iTrader: (1)

if its street tires, then thats there problem

Tuner Eddy

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dual Cam Racing &raquo;</TD></TR><TR><TD CLASS="quote">if its street tires, then thats there problem</TD></TR></TABLE>

i believe it was. I appreciate all the info fella's. I'm still highly considering picking up this kit.

highschooler

The reason why they make good hp but dont run good times is because these type of superchargers make more boost as rpm increases, so they show good peak numbers, but they dont have as good of a powerband(area under the curve) as other superchargers.

TorganFM.

Which doesn't matter in drag racing because you're only in lower rpms for a fraction of a second, if that.

tokesGTR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DanW &raquo;</TD></TR><TR><TD CLASS="quote">Which doesn't matter in drag racing because you're only in lower rpms for a fraction of a second, if that.</TD></TR></TABLE>

Yes, it does.

Check out SiRacer's dyno sheet from Clubsi. 350 WHP at 8600 RPM's. Peak torque is also at 8600 RPM's. Lets say he pulls through 3rd gear, shifts at 8600. His RPM's drop from 8600 to 6600, where instead of making 350 WHP it's making a WHOPPING 212 WHP. Compare that to a turbo car making the same power. Closest sheet I could find quickly was a guy making 406 WHP on a T3/TO4E 57-trim. If he shifts at 8600 and then falls to 6600 RPM's, instead of making less than 2/3rds his peak power, he drops down to 375 WHP. You're accelerating at that point with way more power than you do with a Vortech. Even directly scaling down the 400 WHP graph to show 350 as peak WHP, it would be like making 350 WHP at 8600, shifting and falling to 6600 RPM's and still making 323 WHP. So the turbo has a 100 WHP advantage even at 6600 RPM's. That 350 WHP Vortech SI doesn't cross over 300 WHP untill 7500 RPM's, while the turbo car is making 300 WHP at ~5600 RPM's. Vortech's simply do not have a lot of mid range power, and that's why you're not going nearly as fast for the same peak HP number.

Yeah, it really does matter when you're talking about drag racing.

MotorMouth

i had a vortech on my gsr powered coupe. it was a great daily kit. but being a centrifical charger it does not make any power at all til the higher rpms. when i ran it i spun til the 1/8th just about and only ran a 13.8 at 104mph. launched a little too high and when it got into boost there was no traction. i got rid of it and now have a turbo setup. way more options on a turbo setup with boost levels. its hard to get more than 14 pounds out of that charger without having to go with custom pulleys(which can be very expensive). and besides the whole point of a supercharger in my eyes now is that they are for low end fun boost and driveability. having owned one i would not reccomend it to anyone. plus if you dont have a/c you have to put a compressor on there to run the dam belt.

lilbinky

Buy it, boost it, 9lbs @ 235hp!

tokesGTR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lilbinky &raquo;</TD></TR><TR><TD CLASS="quote">Buy it, boost it, 9lbs @ 235hp! </TD></TR></TABLE>

235 HP that's as fast as a 190 HP turbo car

kineticgsr

I just re-installed my kit on my GSR

I use my car for track days so excessive heat ( turbo)was an issue along with the shape of the power curve.

I loved it before , it made 285 whp @ 8psi ( slipping belt)

Now its 322 @ 14psi with 10 degrees less timing pretty much everywhere ( and another 30k miles on the motor with 12 drack days on it)

I agree that turbos are more efficient at power production, but I like how the Vortech just enhances the curve...not reshapes it.

I will be back on track with it this weekend for a NASA event so I will let everyone know how it goes


oh yah... my best time was 14.2 @101.5 launching soft from 4000 rpms on 17" street tires

I ran it one time when the kit was new and only making 243 whp @ 6psi

and I don't have cruise any more and NOT running AC compressor....you just get a different sized belt

GodFather of Boost

has anybody with a vortech supercharger ever tried running a 25-30lb pulley but add a popoff valve to control the boost at 15lbs. should make a much better powerband

tokesGTR

Overspinning the blower = wasting a lot of power and heating up the air for nothing

GodFather of Boost

with a good intercooler i dont see a problem.

tokesGTR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GodFather of Boost &raquo;</TD></TR><TR><TD CLASS="quote">with a good intercooler i dont see a problem. </TD></TR></TABLE>

You're still going to have higher IAT's, and you're still taking more power to drive the supercharger than you would if it were just pullied for 15 psi.

So, instead of trying some ghetto fixes to make a Vortech behave like a turbo, why not just run a turbo

oneludesol

have a look at a dyno sheet of one of those 300 whp vortech setups, the power curve looks like it was drawn by an epileptic 3rd grader... that should explain enough

Dialectic

Vortechs SUCK!! I had one running 8 & 10 PSI. When I got it tuned you have to feed it so much fuel since the blower is constantly in boost at low RPMs. It burned twice as much gas as a turbo. The power was decent at high RPMs but I kept breaking belts even from the Payne Technologies 8 rib set up so I got rid of it and went turbo. They're a headache and I wouldn't do it again.

PickleTeg

iTrader: (2)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tokesGTR &raquo;</TD></TR><TR><TD CLASS="quote">

235 HP that's as fast as a 190 HP turbo car </TD></TR></TABLE>

Yup

GodFather of Boost

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tokesGTR &raquo;</TD></TR><TR><TD CLASS="quote">
So, instead of trying some ghetto fixes to make a Vortech behave like a turbo, why not just run a turbo </TD></TR></TABLE>
I definitely agree with you on that but some people insist on doing thing different. Even though its good to try new things.
I would settle for 10-20less hp if i would have a better powerband. It might be worth a try if someone already has the vortech. might not look good on paper but could actually result in a faster car.

kineticgsr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dialectic &raquo;</TD></TR><TR><TD CLASS="quote">Vortechs SUCK!! I had one running 8 & 10 PSI. When I got it tuned you have to feed it so much fuel since the blower is constantly in boost at low RPMs. It burned twice as much gas as a turbo. The power was decent at high RPMs but I kept breaking belts even from the Payne Technologies 8 rib set up so I got rid of it and went turbo. They're a headache and I wouldn't do it again.</TD></TR></TABLE>


I get the same if not better gas milage with my Vortech.............

and it works great for me @ the road course....its an NA power curve...on crack!

no sudden rush of turbo power.....no heat management issues..... just lots of me passing cars......

kineticgsr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by oneludesol &raquo;</TD></TR><TR><TD CLASS="quote">have a look at a dyno sheet of one of those 300 whp vortech setups, the power curve looks like it was drawn by an epileptic 3rd grader... that should explain enough</TD></TR></TABLE>


looks pretty smooth to me....

this was from Wednesday night


its running out of injector so redline is actually 8300......I shift @ 8000

oneludesol

Ill give you half credit, that is a really smooth, decent power curve for a vortech, but this is what you get with a turbo, same situation, but maxing out my injectors at 7200...

tokesGTR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kineticgsr &raquo;</TD></TR><TR><TD CLASS="quote">


looks pretty smooth to me....

this was from Wednesday night


its running out of injector so redline is actually 8300......I shift @ 8000

</TD></TR></TABLE>

And peak torque is at 8000+ RPM's. Hooray.

http://forums.evans-tuning.com...=4628

Compare your curve to that turbo curve.

Between 3500-7500 RPM's, where it matters most to road race, you're getting **** kicked by an average of 55 WHP from a car making the same peak WHP.

I'll take that "sudden rush of power" that's easily modulated by throttle to have a ton more mid range power any day, thank you kindly.

PickleTeg

iTrader: (2)

Compare that to this curve:




This a JRSC mind you, so I make great lowend power. Superchargers and turbos have their advantages and disadvantages. Unfortunately, centrifugal superchargers have none of the advantages of a roots blower and none of the advantages of a turbo....it is lose lose for these on a 4 cyl engine. In a V8 application these are awesome because a V8 has it's own low end torque where as a Honda engine has none at all. I am a JRSC nut (see sig) and I am telling you to slap a turbo kit on that thing if you want high end power...at least you get a fatter torque curve.