as far as racing from a roll, it'll depend a little on what mph and rpm the race starts in. But in most cases at the instant of the start of the race, the vortech will probably jump slightly ahead since the turbo will take a faction of a second to start spooling up, but after that tiny wait when it does spool up it'll pull ahead from there on out when it reaches higher boost than the vortech

things get a bit more interesting when you start changing gearing. A lot of turbo guys end up going with the 3.3 final drive to help with traction and less shifting, better gas mileage etc
the vortech guys usually go the opposite route and go for the 3.7 or 3.9 FD, (or 3.5 FD if they're auto) so that the car accellerates into the upper powerband sooner and more gear torque instead of engine torque

then the rpms etc would be drastically different in a roll on race and there will still be certain mph starts that one is in a better position than the other

 

ET really doesn't mean much in the grand scheme of things.

Anyway, one of the main plusses of a turbo setup over a supercharged setup is expandability and the ability to run higher boost if you drop in some race gas or something on the track. It's easy to get a utec tune and crank the EBC to 11psi while running c16 for more power. It's near impossible to do that in any reasonable time on a supercharged setup.

Anyway, this really isn't a debate. A turbo car is more suited for the drag strip. Supercharged cars are more suited toward autocrossing and the like...

 

Really? A half second? Have you ever driven a turbo setup or is this more of your bench racing?

 

I'm running 11 psi, and could go to 12 psi if I wanted with the vortech setup.

All you need is the 2.87 pulley and 34 cog pulley to reach 450-500whp and increase timing more with race gas

 

going from cruising throttle to WOT throttle at around 4-5k rpms, yeah I can't see a turbo fully spooling THAT much faster than a half second. Maybe the JWT TT would be fully spooled in .3 seconds though

come on, you really think half a second is an eternity?

 

On a built motor, right?

I'm talking stock block.

I'm not going to keep pushing anything with you as I've seen how previous turbo vs supercharger threads have gone. Those that know the basics of both types of systems should know which is "better" for them.

 

i'm on the stock block

I have cams, that's all I've done to the engine itself


besides, what does that matter? would you run 11-12 psi from a TN or APS ST on a stock block with 500-530 lbs of tq?
most people wouldn't, but several people run 11-12 psi with vortech's and haven't blown up yet even after ten's of thousands of miles

not counting those people trying to push the limits and trying to blow their engine with 500-550 whp/tq, it seems like 9-10 psi with a turbo is the most anyone usually takes the stock block up to on average


I agree, most people know enough basics to know what they want.
I don't really think ST's have that much more potential than the vortech though other than a much higher tq number. Both ST's and vortech's have their own limitations of how far they can be taken to and it gets hairy comparing them at higher power levels since you can end up changing every single part in the kits to where it really isn't the original kit anymore

 

 

I've got the APS ST tuned to 11lbs by GRD (425whp, 440wtq) and haven't had any issues with the motor. The car currently is having an electrical problem resolved tho...

In either case, I do think most don't go past 10psi on stock block, but there are a few others that have gone to 12psi like JoeDirt.

 

11psi isnt going to get 95% of the SCed cars over 420whp....and 90% of the twin turbo cars with 11psi are close if not over 500whp . Any of us can go find a happy dyno to give us a number.

Again...In this thread the OP asked about his car running both a SC or a ST . If you run them at the same psi , the ST will win

 

Just to chime in here--

My Greddy Twin turbo'd 2.5 inch testpipe/exhaust G35 coupe--

Dyno sheet shows full boost from 3k-6.5k nooo lag.

Also I can go from a 20vac to 4.5psi just as fast as a positive displacement supercharger would. (Mainly because Its only 4.5 pounds).

You have to remember vortech is centrifugal, just like turbos. If your compairing Stillen and Greddy/JWT/PE/APS TT's at 9+ Pounds, You'll have that fraction of a second jump.

But when you are compairing centrifugal superchargers to TT's... at 9psi+.. The power (torque) difference at comperable Horsepower ratings will more than make up for any tiny tiny amount of lag the turbo MAY have behind the supercharger.

The centrifugal is the problem.


I don't have much centrifugal exp, But I know a good deal about them,


+1 for whoever said "Bench Racing" I had to do one of those

OOOOOOOOOOOOOOOooooooooooooooooo's you see from that mtv show "Yo mama"

 

full boost by 3k might be possible if you're in 5th gear and start your dyno run at 2000 rpms, but you will not instantly get full boost at 3000 rpms if you start a dyno at 3000 rpms, especially in lower gears - try it

do a 3rd gear dyno starting at 3000 rpms and post the graph and the old one. You won't make full boost until like 3500-4000rpms

 

Like you said, do you think a half second is an eternity? That "half second" that the turbo is spooling wouldn't be enough time for the supercharged car to make up for it's torque/power delivery disadvantage in a race.

 

yeah if everything else being equal that's true, but then again how often is everything equal?
Each setup their own path of upgrades that compliment that setup that might not work well for the other



the first thing that comes to mind is gearing, like a vortech with 3.9 final drive vs a turbo with 3.5 or 3.3 gearing


think of a roll race at 40mph:
the vortech with 3.9 would be at 4700 rpms making whatever hp at that rpm while the 3.3 FD turbo car is at 4000 rpms making around the same hp or possibly a little more at that rpm.

But unless you brake boost, even at 4000 rpms the turbo car will have a slight half second delay as the turbo spools up.
In addition to being at a high enough rpm to make some decent hp and not having to wait a half second for the power to kick in, the vortech with 3.9 has a 16.68% gear tq advantage which for a car with 325 tq is like adding 54 more tq as far as the initial jump at the start of a roll race

How the race might finish out at whatever final speed, who knows who'd win. It'd depend on the speed you race to because of the shift points being different. There might be some back and forth racing going on at the higher speeds. As you reach higher gears, the rpms you start each gear out in get higher and higher. This starts reducing the vortech's low midrange engine torqe disadvantage since 4th-6th gear start a little over 5000 rpms (assuming redline is 6600 rpms)



but yeah if all other things are equal, the vortech is ultimately at a disadvantage to the turbo car in straight line speed because it has no way to compensate for the lack of tq, even with the instant-on initial boost. I think pretty much everyone has said that multiple times now

 

both are great setups but the best mod for BOTH = DRIVER MOD

 

yes, i did 12.2@115 on my falkens. My best trap speed is 116.8 all under 400rwhp.

The 12.1 on dr's was right after i put the vortech on and was still learning to drive it again. On dr's i could bust that now, but i run on street tires everywhere i go. So that is what i race at the track on, granted i don't hook in 1st or 2nd on the street.

 

+1 Somebody that understands this theoretical racing is a joke...

 

The bottom line is in the end its the man not the machine (old quote) who wins the race. If the same man ran two Zs one with a 400 WHP cent. SC and one with a ST at 400 WHP the ST Z would win all day every day. There is no way that SC Z is going to make up for the torque production of the turbo car.

 

+1
pretty much

 

You are my hero!! Hopefully I will be able to hit those kind of times too.