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I have a thought that I wanted you guys to give me some input on that I can't seen to get anyone elsewhere to comment on. The LS3 puts down more rwhp and especially more rwtq than it's predecessor, the LS2. Now, assuming that GM keeps the same level of torque management in the LS3 C6s, is it safe to assume that because the LS3 produces more rwtq/ more torque over all, it will be effected moreso by the TM settings in the computer? Case in point: the LS2 1/4 mile times on avg are 12.5's or so with a 2.0 60ft . TM will come in as the torque is increased and will not fade out until higher speeds are reached to decrease the amount of torque registered by the pcm. Thats pretty much as how I understand the TM in the C6, so if the LS3 provides more tq upon launch and gear shifting, then it seems to me , the TM would kick in faster and stay in longer than in the LS2 and decrease a good % of the gains seen by the stronger LS3. There has been some thinking as to the LS3 possibly making it into the 11's bone stock, which I think is silly, seeing as it's only 30-36 more HP than the LS2, and 30-40 HP is not going to make that big of a difference. Bone stock LS2 best times are 12.2 in the 1/4, and that was with perfect launch, weather,and luck with the computer not pulling timing or appling too much TM. With what is stated as only 30-36 more HP in the LS3, I cannot even see a .1 improvement in the 1/4 mile times unless the TM set up is greatly reduced from the factory to allow for a higher output of tq to be used before it's stifled. What are your thoughts?
 

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:huh: I'm no engineer,but I'll agree with you:thumbsup:
More rwtq means more to me than hp,I guess?:surprised
Just my .02 :D
 

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The LS3 Torque curve is much diffferent than the LS2 with Torque being lower and low and high RPMS than the LS2 but a higher mid range torque/hp reading. The Cam design may be part of GM's torque management strategy for the LS3.

:cheers:
 

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There is some good logic there, but....
One has to ask, and maybe someone here knows, what is the component in the drive train GM is most trying to save with its TM? Here is my thinking; Both slushbox and manual are now stronger trannys. If the tranny is the main component GM is worried about, then with the stronger one, TM might be dialed back. If this is the case, you can expect 11 second 1/4 times due to BOTH the extra HP and perhaps LESS intrusive TM.

Just a thought.
-Dale
 

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I have noticed TM much more on my manual tranny cars.

My automatic though not as powerfukl, easily ran a [email protected] with the 1/8th at [email protected] on a 1.92 60'.

Now, my 2006 C6 manual tranny ran a [email protected] on a [email protected] 1/8th on a 2.02 60'. This was with cai and catback on a stock tune.

Here is where things get weird....

I added headers, stat, and a tune to the 2006 and it made 370-378rwhp, I tried three different tunes, any time my 1/8th mile traps went up to 89+ mph my 1/4 traps dropped to 114s.

Only when my 1/8th mile traps were in the 88s did I see 115s and twice I saw 116.02 and 116.22.

Not only that, even with the added 30rwhp, my car never got below [email protected] on a 2.05 60'.

Something slowed the car down with more power?

Was it TM?

If so, how will the LS3s handle the same power?

Notice, my new 2006 C6 Vert manual tranny only has cai, catback, and a stock tune;)

Howard
 

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Discussion Starter #6
I have noticed TM much more on my manual tranny cars.

My automatic though not as powerfukl, easily ran a [email protected] with the 1/8th at [email protected] on a 1.92 60'.

Now, my 2006 C6 manual tranny ran a [email protected] on a [email protected] 1/8th on a 2.02 60'. This was with cai and catback on a stock tune.

Here is where things get weird....

I added headers, stat, and a tune to the 2006 and it made 370-378rwhp, I tried three different tunes, any time my 1/8th mile traps went up to 89+ mph my 1/4 traps dropped to 114s.

Only when my 1/8th mile traps were in the 88s did I see 115s and twice I saw 116.02 and 116.22.

Not only that, even with the added 30rwhp, my car never got below [email protected] on a 2.05 60'.

Something slowed the car down with more power?

Was it TM?

If so, how will the LS3s handle the same power?

Notice, my new 2006 C6 Vert manual tranny only has cai, catback, and a stock tune;)

Howard
I hear ya, man.....I have almost 50 more rwhp than I did when I ran 12.0 flat in the 1/4 and am turning 12.2's all day now with a 120+ trap speed and identical 60fts to the 12.0 run. WTF. I know some may be the weather, being hotter and all the humidity, but....c'mon....I mean...damn....lol. BTW, the post before yours, I belive....no, you won't see 11 sec slips from ONLY 30-36 extra bhp, but if they do something different with the computer/tm, you could see 12 flats. BTW2: that weak part in the C6s is the shaft, not the tranny. It's the only part I've seen fail besides the diff on a C6 to this point.
 

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For 0-60 or 1/4 mile times it is not the peak torque (HP is a calculated value = Torque*RPM/5252) but the area under the torque vs time curve. So if you measured your rpm at each second and then graphed your torque (from the torque curve) vs time and determined the area under that curve the car that had the highest value would be the faster (all other things being equal).

So if the LS2 has flat torque curve it may still be a faster engine if the area under the torque vs time curve is larger.

Anyway I think this is true. Any dissenters?
 
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