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Keaton · Joined: 02 Jan 2006 Posts: 261 Location: 85202

would a 931 with an intercooler and springed turbo be able to take on a stock 05 GTO 5.7L 3200+lbs?? what to you guys think?

Khal · Posted: Sun Feb 26, 2006 5:21 pm Post subject:

I think it doesn't matter.
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morghen · Joined: 21 Jan 2005 Posts: 9095 Location: Romania

it dosent matter....but a turbo engine...you can say it almost has no limits....so yea i guess 931 would win.
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Khal · Posted: Sun Feb 26, 2006 7:28 pm Post subject:

Well alright, if we're running with hypotheticals...

I assume by "05 GTO" you mean this..?

If so, then you're talking about what we call a "Monaro" down here. I know them well.

The short answer, in a straight drag race, is probably no. The GTO pumps out at least 320hp... the new ones have 400hp. The torque is stupendous. Their rolling-start acceleration is phenomenal. Their top speed is more than 150mph.

A 924 Turbo with an intercooler and 1 bar boost might pull, say, 220-230hp? Torque would be impressive for a 2-litre but not a patch on the GTO. Rolling-start acceleration would also be good. But again, I doubt you'd be anywhere near a GTO. Top speed is limited by gearing. I doubt you'd pull much higher than 150mph... probably a bit lower.

As an example, a friend of mine hired a Ford Falcon for a coast-bound dirty weekend with his GF. We decided to put my car up against it. From a 35mph rolling start, I couldn't outrun him. I never lost ground... but I didn't gain any either. The Falcon weighs about 1800kg or 4000lbs! (vs. about 1200kg for my car). It has about 240hp from a four-litre in-line six, compared to 170-odd hp for my two-litre turbo four. It has at least 40% more torque. The top speeds are similar (in theory, at least... the Falcon is electronically limited to about 110mph).

With another 40-50hp (i.e. with an intercooler and 1 bar boost), I reckon I could outrun the Falcon. But the GTO would paste us both...
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'80 924 Turbo

J1NX3D · Joined: 06 Feb 2003 Posts: 1333 Location: New Zealand

i read this a lil while back on rennlist. A 951 would run with them, a 931?? ...
http://forums.rennlist.com/rennforums/showthread.php?t=250775&highlight=GTO
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morghen · Joined: 21 Jan 2005 Posts: 9095 Location: Romania

after reading that i think a 931 would loose...but not by much.
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sequential · Joined: 18 Nov 2005 Posts: 500 Location: BANNED

[quote="Khal"]Well alright, if we're running with hypotheticals...

I assume by "05 GTO" you mean this..?

I

As an example, a friend of mine hired a Ford Falcon for a coast-bound dirty weekend with his GF.

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For a coast bound dirty weekend, wow that sounds like a lot of cleaning went on there khal!
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Paul · Posted: Mon Feb 27, 2006 12:55 am Post subject:

C'mon a 1980 car competing with a 2006 muscle car? The 931 was compared against a corvette and a ferrari in 1980 and although it was not embarrased, it did not win the 0-60 race.
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Khal · Posted: Mon Feb 27, 2006 6:31 am Post subject:

924 turbo · Posted: Mon Feb 27, 2006 5:27 pm Post subject: Re: 931 Vs 05 GTO

morghen · Joined: 21 Jan 2005 Posts: 9095 Location: Romania

i dont know khal..this diagram i found in my 924 manual looks preety good.

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Khal · Posted: Tue Feb 28, 2006 6:55 am Post subject:

Yeah, that's a nice looking diagram morghen.

Two things, though:

Although power rises steadily until about 5,500rpm, it trails off pretty quickly after that. And at about 3,500rpm it is only producing half its power, which is around 60hp... and that's at the flywheel. It'd be considerably less at the wheels.

And secondly, torque trails off after 4,000rpm. And its peak torque is much less than half of what the four-litre Ford has, probably a third of what the GTO would produce.

The 924's peak acceleration would be from about 3,000rpm through to 4,000rpm, where both power and torque are rising together. After that, acceleration would trail off. You would still be accelerating to redline, sure. But it wouldn't be accelerating quickly that high in the rev range.

The GTO produces its peak power and torque at about the same revs... but it's 3 times the power and torque that the 924 produces. That's 300% more powerful

And it's only about 30% heavier...

Think about it... when the 924 is producing 60-flywheel-hp, the GTO is probably pushing well in excess of the 924's peak power.

Another thing to consider is that the Turbo, with it's lower compression and being off boost under about 3,000rpm is not much quicker, if at all, that the NA 924 -it depends mainly on gearing, which I'm not 100% sure about. But the Turbo has a very low 1st gear.
Of course, after about 3,000rpm the turbo kicks in and power doubles almost instantly, which helps

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'80 924 Turbo

Keaton · Joined: 02 Jan 2006 Posts: 261 Location: 85202

ok so........
400hp at the fly -20% ~ 320hp at the wheel 3725lbs ~11.64 lbs per hp
125hp-30% ~ 87.5 at the wheel. 2344lbs/87.5 ~ 26.78 lbs per hp
but thats stock intercooler(10-15% right??) and spring (lets say about 1 bar of boost) how much more power for a 931??

LS1 5.7L V8
2.0L in line four

Khal · Posted: Tue Feb 28, 2006 7:21 am Post subject:

flosho · Posted: Tue Feb 28, 2006 7:30 am Post subject:

The only way a 931 has a shot in hell at catching a GTO is if its the ls1 automatic version.. the ls2 version puts out more hp.

I would say a 931 with some weight reduction, intercooler, and 15psi could pull a stock GTO.

I've launched my car before, and if you do it right, you wont have ANY lag time, as short as our first gears are, you're ripping into second before the GTO can hook up(ok, maybe not that bad, the auto GTO's don't have that much of a traction problem).

Of course like kahl says, give them a turn, and those pigs are toast.

BTW, my car weighed just over 2600lbs so I dont know where the 2300lb weight came from.
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