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Retired LEO meow
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Discussion Starter #1
From reading in certain posts, the GTO tops out between 162-165 mph governed. If the top speed limiter is eliminated, I was curious what is the top speed of the GTO? Also, what would you guess the LS1 is capable for maximum hp/tq gains (Such as adding a S/C, nitrous, heads, cam, etc) before problems with the motor start?
 

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No More GTO!!!!
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Do you really want to find out? 165 is plenty for me.
 

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Retired LEO meow
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Discussion Starter #3
Bone said:
Do you really want to find out? 165 is plenty for me.
Yes I would. :)
 

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Premium Member
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TprGTO said:
From reading in certain posts, the GTO tops out between 162-165 mph governed. If the top speed limiter is eliminated, I was curious what is the top speed of the GTO? Also, what would you guess the LS1 is capable for maximum hp/tq gains (Such as adding a S/C, nitrous, heads, cam, etc) before problems with the motor start?
DY set mine @ 255 :D :gr_devil:
 

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Great Lakes Moderator
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I thought I heard we had a 155mph limiter, and those that have gone above have removed the limit function from the computer...
 

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Seriously?
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I think Pontiac and several of the Mags list the top as 155 governed. My guess is there is only one way to find out.................

As far as what the LS1 block can handle, I think the neighborhood of around 500 HP or so is not unreasonable, PROVIDED, the car is tuned in a conservative to mediocre fashion. If you go for overkill on the tune, rest assured that connecting rods will try to pop out and say hello. Pushing the car at every accessive chance certainly doesn't help longevity either. So I would say, if you do forced induction, or a stroker engine, or a heavily modified stocker, tune it right and don't beat on it constantly, and it will last.

My .02,
Matt
 

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Resident 10-second Priest
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TprGTO said:
From reading in certain posts, the GTO tops out between 162-165 mph governed. If the top speed limiter is eliminated, I was curious what is the top speed of the GTO? Also, what would you guess the LS1 is capable for maximum hp/tq gains (Such as adding a S/C, nitrous, heads, cam, etc) before problems with the motor start?
I think 160 or so is the safest you could reach. The motor, stock, could reach it pretty easily, but you gotta worry about tires and aerodynamics. Above that speed, if a tire goes at that speed, you're dead. If you hit a dip in the road or a gust of wind, you're dead.

Only worries about the motor, as Old Goat has pointed out, is burning oil. Pontiac recommends topping off with an extra quart or two if you're at the track doing extended high-speed runs.

SyGoat has told us his Autobahn experiences, and it sounds like the Goat is real comfortable doing extended runs at 140.

Let me just say, hypothetically :sneaky: , that 160 is scary fast :eek2: . With my horsepower, I could easily reach 170, and 180 if I was suicidal.

Padre
 

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May I quote you on that?
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I'm a little more conservative and consider 130-140 to be the safe upper limit for off track driving. Even there, it had better be God's gift to asphalt. There are just too many variables, as Padre mentioned. If you look at cars designed to go faster, they are a whole different animal as regards aerodynamics, tires, brakes, driver protection, and price.
 

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Moving Forward
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mistermike said:
I'm a little more conservative and consider 130-140 to be the safe upper limit for off track driving. Even there, it had better be God's gift to asphalt. There are just too many variables, as Padre mentioned. If you look at cars designed to go faster, they are a whole different animal as regards aerodynamics, tires, brakes, driver protection, and price.
I thought the top speed of the GTO was Drag limited. I don't remember ever seeing a govener limited speed ever listed in any spec sheets. As for top speed, I thought that the rules for cars in the us is limitation by quality. That is if a vehicle can do 120mph and the manufacturer puts on 110mph max tires then the top speed will be governed to 110mph. I have a friend who has a Chevy Blazer and he said it tops out at around 98mph and will not go beyond and was wondering why. I ask a knowledgable friend about the governed speed and he said the factory tires probably could not handle much more beyond 98mph. Is this correct?
I think top speed is a area where you start to risk you life based on the chance that nothing happens. I think Sigo pretty much showed the potential of the GTO and the quality of stock parts and wheels. I don't think i would want to drive 165 for much more then a few seconds, plus the fact that i'd be doing 100 miles over the speed limit on the fastest roads in my state. I also don't want to hurt the car. I think 140's is faster then almost every car on the road today. When i hit that (when the car is finally broken in and has an oil change) I'll have an extra SEG.

I also don't think any road in my state was ever tested for 165mph let alone 140mph, i wonder.
 

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Razinhell said:
I thought the top speed of the GTO was Drag limited. I don't remember ever seeing a govener limited speed ever listed in any spec sheets.
It's definitely limited by the computer (in fact you can just get LS1edit or HP Tuners and check it). A fuel-cut kicks in that feels like traction control (the accelerator pushes back at you). For the A4, this is at around 5000rpms in overdrive, which means it has the potential for more, especially if you're not stock.

Or so they tell me. :sneaky:

Padre
 

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Go Tigers!
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I love drag racing(haven't been yet with the goat, will soon though), but going
130, 140, 150 and higher is just not something I am comfortable doing. Like Padre said, you blow a tire and it's lights out!
 

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Member #804
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power wise the LS1 short block is good to about 500rwhp, the problems seam to arise when somebody trys to shift at 7000rpm. Course If you put in some Lunati gear the shortblock is good to 1,000 hp, look at the world record LS1 powered car that TA vert. dynos 1100rwhp with a F1R supercharger, runs a 380ci (very oversquare) its a C5R block but still.

It doesn't take alot of power though to get into the 10s with a LS1,the nations fastest cam only car puts down 400rwhp runs 10.91 with nitrous (fbody) that car uses alot of suspension mods, weight saving mods and a 12 bolt diff. Heck BMR basically did a 10.98 on nitrous and a converter with their GTO.
 

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Yes, it has a car seat
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From what I remember the mag's listed 155 electronic shutoff and 162 or 163 theoretical max speed. Now, they also listed like 85 or 87 max in 3rd, and I'm up over 90 before redline...
Dan
 

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I think motoring journos in australia have got the monaro to 268km/h or about 166mph, GTO perhaps capable of a tad more ungoverned
 

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Former Goatherder
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Just going on gear ratios and the assumption that you wouldn't be able to accelerate in 6th gear past 170 mph.... 170 should be about the top speed (6500rpm in 5th). As for automatic, I have no idea. I know I'll never go anywhere near that.
 

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13 year owner
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Well, I've wound mine up to 150'ish! :D

As to power, 500rwhp is pretty stout and yet reliable.

The valvetrain is the weak point in this motor, NOT the rotating assembly necessarily. The LS1 has an oil return problem when RPM's get up to and past 7,000 rpm. Also if you miss shift, flash the vavletrain with an sudden surge in RPM, you'll bend pushrods. The valvetrain also sometimes can have an issue with "floating" at rpm as the vavle springs aren't strong enough to pull the valves back in at that level.
 

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TprGTO said:
From reading in certain posts, the GTO tops out between 162-165 mph governed. If the top speed limiter is eliminated, I was curious what is the top speed of the GTO? Also, what would you guess the LS1 is capable for maximum hp/tq gains (Such as adding a S/C, nitrous, heads, cam, etc) before problems with the motor start?

It is safe to drive faster than 165 in controlled conditions. when you decide to drive fast make sure it is on a day that is not windy, well abouve feezing point, it's not raining, there is no traffic, have a lot of strait away, and its best if there is high side walls so animals like deer cannot cross the road. I rented a mercedes station wagon here in germany and maxed it out to about 160 and even though the speed was kind of scary at first, the car seemed really stable at that speed. just remember, NO sudden movements or fast changes in deceliration and stearing. I test drove a GTO, only up to 100 though and it had the same feel as the mercedes i drove. I bet it might be able to hit 170-175, but I'm not sure because I haven't driven that fast in the GTO and I'm not sure if the power can over come the wind resistance at that speed. it's just a guess at this point.
 
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