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Discussion Starter #1
I went to they dyno today. The results were ok, but not outstanding. We made 2-3 pulls all within 1-1.5hp of eachother. I know I need a tune now. The mailoder tune is not cutting it. It was rich as hell on the dyno. I need my exhaust as well. I don't think the stocker is up to the task. I have a K&N filter on, but I would like to put my CS tube on as well. Anyway, here are the results. 381rwhp and 353.1rwtq. I overlayed the new graph with the old one. You can see how the new hp graph is rich as heck in the bottom part of the power band. AFR's are very conservative. It stayed around 12.0-11.8 through the entire pull and twords redline dipped down to 11.6. Here is the chart.

 

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Magic Blue Bottle
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is 12.5 A/F mixture where we should be or does it depend on the amount work done to each car?

This is my first car that I had to worry about this computer crap...I am used to dealing with carbed engines with lots of plates...this should be an interesting learning curve
 

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Oh my f*ck!
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How many miles are on this vehicle? Is it me or do these numbers seem pretty low for something proclaiming itself a 500HP H/c package (500HP with 15% loss = 425HP @ wheel and that doesn't take into account the other mods you have)?
 

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Discussion Starter #5 (Edited)
Phobos512, you have to take into account their test vehicle has LT headers no cats, a custom tune, and a full exhaust. I am running shorties,cats, stock exhaust and a K&N panel intake w/ a mailorder tune.

The numbers will probably be in the very low 400 range when the exhaust and intake system is on the car and a custom tune is done. I'll just have to wait and see where we end up.

I think the loss through the drivetrain is probably closer to 20% IMHO. Who knows for sure. Even at 20% it is 381/4=95.25x5=476.25 crank hp with the stock exhaust setup and no custom tune. You can't expect to put heads and cams on the car and expect to put 500 without any other mods either. Every head/cam combo out there gives their numbers with full bolt ons and no cats usually. I am just doing mine piece by piece because I can't afford to drop all the cash at once. The car has 2500 miles on it by the way.
 

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Oh my f*ck!
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gtodoug said:
Phobos512, you have to take into account their test vehicle has LT headers no cats, a custom tune, and a full exhaust. I am running shorties,cats, stock exhaust and a K&N panel intake w/ a mailorder tune.

The numbers will probably be in the very low 400 range when the exhaust and intake system is on the car and a custom tune is done. I'll just have to wait and see where we end up.

I think the loss through the drivetrain is probably closer to 20% IMHO. Who knows for sure. Even at 20% it is 381/4=95.25x5=476.25 crank hp with the stock exhaust setup and no custom tune. You can't expect to put heads and cams on the car and expect to put 500 without any other mods either. Every head/cam combo out there gives their numbers with full bolt ons and no cats usually. I am just doing mine piece by piece because I can't afford to drop all the cash at once. The car has 2500 miles on it by the way.
Well then I guess SLP should reevaluate the way in which they advertise their parts. If someone sells me a 500HP kit I'd expect it to give me 500HP. That's all I'm saying.

Aside from the tune, it looks as though you've got a ways of break in to go. The consensus 'round here is the motor is opening up still all the way through 5000mi and perhaps beyond.
 

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Resident 10-second Priest
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Good runs, Doug. I'd figure a 20% loss for the M6. The real proof will be trap speeds at the track, which is all that matters to me. :)

You'll definitely need a tune. Mail-order tunes have to be, by their very nature, conservative, because they have to be generic.

It would be interesting to do a couple of runs with and without the CS tube to see what happens.

Also, I'm trying to figure out why the .005 run hp/tq curves don't match up at 5252? Just a glitch on the printout?

Oh, and what's your redline set at now?

You gotta love the torque curve on these things. In fact, you can't even call it a "curve". More like a "mesa" that slowly tapers off. :)

Padre
 

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Discussion Starter #8
phobos512-when I ordered the kit they did mention that I would need intake, LT headers w/no cat and full exhaust to see the full gains of the kit. Their consensus after I spoke with them and told them what I wanted to do (shorties etc.) was a hp figure in the very low 400 range.

Padre- thanks for the kind words. I have redline set at 6900rpms now.
 

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Doug not bad numbers at all....a custom tune should get you some more....
 

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10 sec club
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PadreGTO said:
Good runs, Doug. I'd figure a 20% loss for the M6. The real proof will be trap speeds at the track,
Unlikely that the driveline loss is anywhere near that high.

Most modern manual transmissions typically lose 12 - 15%

Modern automatic transmissions might lose 20% at most.
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PadreGTO said:
The real proof will be trap speeds at the track
Agreed... :cool:
 

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Angus said:
Unlikely that the driveline loss is anywhere near that high.

Most modern manual transmissions typically lose 12 - 15%

Modern automatic transmissions might lose 20% at most.
Yeah, you're probably right. And on the autos it's even more with a higher stall converter. But unless you actually put the engine on an engine dyno, most crank figures as advertised are :bs: . I wish vendors like SLP and even my own MDMC would just advertise true rear-wheel HP on a realistic dyno (if you know what I mean).

But the proof will be in the trap speeds.

Padre
 

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PadreGTO said:
Also, I'm trying to figure out why the .005 run hp/tq curves don't match up at 5252? Just a glitch on the printout?
The HP scale on the right and the torque scale on the left are not the same. I find it a bit annoying when charts are generated that way, BTW.
 

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Yea, but the RPM range doesn't change and the 005 run crosses at 5,500 which it shouldn't.

It should always cross at 5,252.
 

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Ah! I see what you mean now. Something is definitely goofy. My interpretation would be this: the software allows auto-scaling and that the scales picked for HP and torque are not only different but they are different between runs as well. The physical crossing point on the graph is totally dependent on the two curves using the same scale. To see what I mean, imagine that the torque scale was graduated in 1 ft-lb steps instead of 25 ft-lb steps. The torque curve would shoot waaay up off the page and would intersect the HP curve right at the start. In order for the picture to look right, both HP and torque need to be plotted against the same scale, with the same start-point and increment. Doing otherwise skews the comparison of the two. Additionally, comparing two different runs that use different scales is of limited value, too. Looking more closely, I see that the baseline run not only uses different scales for HP & torque but it also uses a scale that is different than the one used on the 005 run - notice that the curves for the baseline run cross too soon while the curves for the final run cross too late.
 
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