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Old Dec 3, 2006 | 05:18 PM
  #101  
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Originally Posted by taurran
That's also because they're usually making lower torque numbers. A problem with ST setups and longevity is that when you're pushing 400whp, you're usually putting down much higher torque numbers. For instance, on my setup I'm making roughly 420-430ft/lbs of tq at 9psi. On a TT setup with a stock motor people are generally pushing 450-470whp to get that kind of midrange torque. And, as we all know, torque is nice but it's hard on connecting rods.
torque will be dependent on their exhaust piping...
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Old Dec 3, 2006 | 05:20 PM
  #102  
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Originally Posted by doug
torque will be dependent on their exhaust piping...
Yes, but not entirely. Show me a TT making 20-30ft lbs more than whp (that wasnt dynod at VRT).
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Old Dec 3, 2006 | 06:10 PM
  #103  
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Originally Posted by taurran
That's also because they're usually making lower torque numbers. A problem with ST setups and longevity is that when you're pushing 400whp, you're usually putting down much higher torque numbers. For instance, on my setup I'm making roughly 420-430ft/lbs of tq at 9psi. On a TT setup with a stock motor people are generally pushing 450-470whp to get that kind of midrange torque. And, as we all know, torque is nice but it's hard on connecting rods.

craig,

You'd make more HP than Tq too if your could pull harder in the upper rpms. look at your dyno graph, you are peaking around 5700, but at 5300, you are almost at the same level only a small bit off. I think this is due to the hot side restrictions on the Turbonetics Stage 1. If you were to continue making power in a linear fashion, you'd be making more HP than Tq.
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Old Dec 3, 2006 | 06:24 PM
  #104  
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Originally Posted by taurran
Yes, but not entirely. Show me a TT making 20-30ft lbs more than whp (that wasnt dynod at VRT).
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Old Dec 3, 2006 | 07:01 PM
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it was july of last year when i bought the single kit, thats so far back i cant remember if the problems with the tt kits were solved or not, but youre right doug, it doesnt take much to make the tts safe now.

its weird, i put my stock exhaust back on the car today, because im selling everything, and the car feels like it pulls much harder now. dont know if its because the exhaust is quite and i can hear the turbo spooling more, like a psychological thing, or what, but it feels stronger, and its actually holding boost better.

but i agree with taurran, the singles make more tq with less hp. and it does depend a good bit on the exhaust, but even with a 3" i still made 25 more tq even with my horrible boost leak.
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Old Dec 3, 2006 | 07:02 PM
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Originally Posted by doug


Is this your car?

Can you list details on the install?

That is the curve and power I'm looking for.
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Old Dec 3, 2006 | 07:05 PM
  #107  
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Originally Posted by TIMMAHH
Is this your car?

Can you list details on the install?

That is the curve and power I'm looking for.
yeah..

Greddy TT Kit, UTEC, CJM Stg 1, Stock Exhaust

i believe the stock exhaust is why i have more tq than hp... tuned & installed by MRC.. pm Julian (MRC Motorsports) for more details
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Old Dec 3, 2006 | 07:13 PM
  #108  
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Originally Posted by doug
yeah..

Greddy TT Kit, UTEC, CJM Stg 1, Stock Exhaust

i believe the stock exhaust is why i have more tq than hp... tuned & installed by MRC.. pm Julian (MRC Motorsports) for more details

Thank you.

I was about to pull the plug on a greddy kit and this just sold me for sure.

Do I need to have a fuel return kit for a tune like that (~400whp/tq)? I do not plan to run over 7psi without one but money is tight for the initial install and I don't have the extra $1k for a fuel return right now.
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Old Dec 3, 2006 | 07:15 PM
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Originally Posted by QuadCam
craig,

You'd make more HP than Tq too if your could pull harder in the upper rpms. look at your dyno graph, you are peaking around 5700, but at 5300, you are almost at the same level only a small bit off. I think this is due to the hot side restrictions on the Turbonetics Stage 1. If you were to continue making power in a linear fashion, you'd be making more HP than Tq.
I don't think that's entirely the case. Look at APS ST setups. People make much higher torque on them as well. (JoeDirtPharm's comes to mind in particular)

Once I finally get ahold of the stage 1.5 kit I'll see if its possible to tune for more top end power without advancing timing to dangerous levels (we'll see).

Doug, if you're running the stock exhaust with that setup and making that much torque then backpressure would definitely be a big player. All those I've seen running tt's on properly matched exhausts have been making a lot more power/torque.

Last edited by taurran; Dec 3, 2006 at 07:17 PM.
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Old Dec 3, 2006 | 07:19 PM
  #110  
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Originally Posted by TIMMAHH
Thank you.

I was about to pull the plug on a greddy kit and this just sold me for sure.

Do I need to have a fuel return kit for a tune like that (~400whp/tq)? I do not plan to run over 7psi without one but money is tight for the initial install and I don't have the extra $1k for a fuel return right now.
you don't have to.. but the CJM Kit and the ability to control the fuel pressure can only give you more security.. i say talk to Julian or phunk.. i don't want to give you wrong information.. they will know for sure
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Old Dec 3, 2006 | 08:05 PM
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Originally Posted by doug
you don't have to.. but the CJM Kit and the ability to control the fuel pressure can only give you more security.. i say talk to Julian or phunk.. i don't want to give you wrong information.. they will know for sure

Thanks again!
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Old Dec 3, 2006 | 09:13 PM
  #112  
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Originally Posted by taurran
And, as we all know, torque is nice but it's hard on connecting rods.
Wrong. Torque is hard on bearings and cranks, revs are hard on rods.
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Old Dec 3, 2006 | 09:41 PM
  #113  
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Originally Posted by BriGuyMax
Wrong. Torque is hard on bearings and cranks, revs are hard on rods.
So, we should all just save money and use the stock rods for our engines builds? I knew they weren't weak!!
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Old Dec 3, 2006 | 10:02 PM
  #114  
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Originally Posted by thawk408
So, we should all just save money and use the stock rods for our engines builds? I knew they weren't weak!!
Detonation will also break just about any moving part in a motor. And it is responsible for a vast majority of blown VQ motors.
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Old Dec 4, 2006 | 04:13 AM
  #115  
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Originally Posted by BriGuyMax
Wrong. Torque is hard on bearings and cranks, revs are hard on rods.
But both will defeinitely contribute to snappnig weak connecting rods.

Also, I've seen many blown stock motor breakdowns where no physical sign of detonation was present. There have been a few long and drawn out discussions on these forums concerning this.
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Old Dec 4, 2006 | 05:35 AM
  #116  
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The st may make more tq than hp, but the tt are more linear in there tq. They carry the tq to redline where the st's drop off like a brick.
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Old Dec 4, 2006 | 07:02 AM
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Originally Posted by taurran
But both will defeinitely contribute to snappnig weak connecting rods.
That's such a vague statement. Piston speed is is the critical thing for rods. Ask any engine builder. The piston accelerating AWAY from the crack shaft puts more stress on a rod then "torque" (or more correctly "combustion pressure") ever will.

Also, I've seen many blown stock motor breakdowns where no physical sign of detonation was present.
Great, doesn't mean it never detonated. Just means that it wasn't detonating at the time of failure. It's really hard to diagnose what actually caused an engine failure when you have the snowball effect of one part breaking on a rotating assembly.


There have been a few long and drawn out discussions on these forums concerning this.
Yes there are and a lot (not all) of really ignorant individuals posted their uneducated opinions in them.
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Old Dec 4, 2006 | 07:54 AM
  #118  
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Ack.

While its true that most of the stress put on connecting rod is in tension during the intake stroke, the force on rod during compression and ingnition is not entirely in compression of the rod. during most of the stroke, the rod is at an angle, creating a shear stress that can cause the rod to fail.

Torque will not affect engine parts more than HP or visa versa because,

HP AND TORQUE ARE RELATED!!! You can directly relate HP and torque using an equation. HP is TQ*velocity!!! the argument here is about peak numbers and the curve. But if you have a massive HP motor with a low peak TQ than that just means the peak TQ comes at such a high RPM that engine speed swamps the equation. Look at F1 cars, insane peak HP #s with moderate TQ levels.... at 15,000 RPM.

**edit, I got so worked up about the HP/TQ thing I forgot to mention the initial thread topic...

TTs are generally more efficient for V or flat setups. STs are more efficient for Inline setups. Quads are effiecient for W setups, and the most efficient performance enhancer for a wenkel is to swap it for an LS7. Just look into it. There are losses inherent in a turbo kit, and different kits are better for different applications.

Last edited by 03BrickyardZ; Dec 4, 2006 at 08:11 AM.
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Old Dec 4, 2006 | 08:10 AM
  #119  
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Originally Posted by 03BrickyardZ
and the most efficient performance enhancer for a wenkel is to swap it for an LS7.
don't let the lsxdoesntbelonginanFD club hear you say that
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Old Dec 4, 2006 | 08:14 AM
  #120  
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Originally Posted by 03BrickyardZ
Ack.

While its true that most of the stress put on connecting rod is in tension during the intake stroke, the force on rod during compression and ingnition is not entirely in compression of the rod. during most of the stroke, the rod is at an angle, creating a shear stress that can cause the rod to fail.
Actually I was talking about the exhaust stroke. When the rod is at an angle the piston is not changing direction. The direction change is what puts the most stress on the rod and it only happens at the top of the stroke or the bottom of the stroke when the rod is exactly perpendicular to the force being applied.
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