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Discussion Starter #1
Just got back from the track and knocked almost 8/10th off my quarter mile times! If you haven't seen my previous post, the best time I was able to get with the car completely stock was [email protected] The weather was almost identical today. This is an A4 car with a little over 1500 miles. The car loves mods and responds very well to them. The mods responsible for this ET are:

- Vigilante 2600 stall converter
- BFG 275/40R17 Drag TA's on stock wheels (the fenderwell lip had to be rolled for these to clear)
- Removed 115 lbs from the car (motor skid plate, trunk brace, spare tire, jack, and wheel chocks, torque converter weighed 25 lbs. less than stock!) - most of this weight was removed at the track in about 20 minutes.
- Unifilter cold air intake
- Removed MAF screen
- Bypassed water through throttle body

The car was going consistent 1.8 60 ft/times with a best of 1.779. I think it will take either more motor or a higher stall converter to lower the 60 ft any more than this. I am happy with the 60 fts, but it still seems like the mph is a little low. After seeing Speed Inc's dyno results for their upcoming GTO headers, I think a set would easily put this car into the 12.80's. In the meantime, I have a ported throttlebody and an electric Meziere water pump coming. If we have another good weather day, it might run 12's even before the headers arrive! :bubbrub
 

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Nice! Maybe better broken in the mph picks up too?
 

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Great result for such simple mods.

Mick
 

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Nice ET!!.. Only thing is the MPH doesnt seem right. You dropped 8/10 off your et, your 60' time only dropped .2 sec. Your MPH should be much higher .

I have only been to the track once with my 03mustang. My best was 13.83 @104.67 with a 2.22 60' time and horrible traction. Something dosent jive.

Either way nice times. :)
 

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- Removed MAF screen
The general consensus I've gotten from ls1tech is that this messes with the a/f mixture. Most that have dyno'd with and without suggest leaving it on. I'm assuming the car hasn't been tuned yet?
 

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Discussion Starter #7
I agree, the mph should be higher which basically means the car is not making any more hp than before. The only power mod performed was the cold air intake and that netted 2 mph which is about right for 10-15hp. The rest of the gain was from weight loss and better 60 ft/times (due to the converter). I still think that the car should mph around 104, maybe 105 and it might after the motor gets fully broken in. I had a '00 WS6 TA that would mph around 104 stock and a '00 Vette that did 107 stock. The MAF screen was removed because the car felt fat up top and we were trying to lean it out a little. Don't know if this helped it or hurt it, we did too many other things at the same time to really know until we get the car tuned and view the a/f tables.
I think with the above mods, headers, and tuning, these cars wil run 12.60's without a problem. That puts it really close to ZO6 territory for about $2k worth of mods and the car is still 400 lbs heavier!
 

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tterbo said:
..........The mods responsible for this ET are: Vigilante 2600 stall converter.....................
Can you explain something to me. I am not that familiar with the inner workings of an automatic. What is a "2600 stall converter"? Is that the torque converter? Does the 2600 mean you do not start to accelerate from a stop until the rpm reaches 2600? How would/does that affect daily driving?

I am going to be getting an automatice due to traffic congestion and want to modify as much as possible so any information you can give me regarding automatics will be appreciated. :)
 

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I think for an auto your E.T. is better than expected but I agree that your MPH should be 104+.
Did it spin the tires? Or did it bog off the line?
 

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heh, I have a feeling torque management may be the culprit.

While he's done a lot to kick up the performance between the shifts, I bet the TM is holding the shift performance down, and that is probably the cause of the lower mph.

Though realize it isn't how fast you cross the line as much as it is how quick you get there.
 

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That's a great time for a lightly modded car with only 1500 miles! I wouldn't read too much into the trap speed. As others have said, let the motor break in a little, then the trap speed will surely rise some. The motor is tuned for low end torque, which may hurt some in the big end, especially compared to LS1 f-bodies and vettes. I would say most of the gain in ET was from the improved launch and stall. For every .1 in 60' you gain about .2 in ET. So your DR's knocked about .4 off your ET, weight reduction .1 and the stall/CAI .3. Not bad! Give it another 3K miles and good weather, and you may see 12's without doing anything more. :)
 

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Discussion Starter #15
B4Z - After a good burnout, no tirespin at all and no bog. We experimented flashing the converter and foot braking it and the best result was foot braking it at 2600 rpm. I started with a 1500 rpm launch, then 2000, then 2600. Each time it ran a quicker ET so a looser converter might even yield better times if the tires hold traction. I had a 3500 stall in my WS6 and it was a little much for me on the street so I chose a smaller one this time and am much happier with the streetability.

Tiggerfan - thanks for the converter link, that saved a very long post. I agree that torque management is holding the car back some. The 2-3 shift could be a little better too, it just takes way too long to make the shift. It sounds like LS1edit is about ready so maybe I can get that adjusted soon.

Ude-Lose - Went to Bradenton, FL. My scanner broke but I'll take some pictures of the timeslips tomorrow and post them.

GTP-GTO - Yeah, I think if the motor already had 5000 miles on it, I may have seen a 12 second ET already.
 

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DevilYellow said:
I'm worried about the driveshaft setup, so far its holding up I suppose. Have you taken a close look at it?
You have good reason to be worried about the drive shaft setup. I sheared the front rubber donut off the tail shaft on Friday night at our local drag meet. Tore a 2" gash in the floor pan and did a fair bit of under body damage as it thrashed around. Luckily it was off the line and not at speed.

My car is not stock, but it is not a montster either (around 360rwhp).

I am now in the process of installing an earlier model tail shaft which ironically was a much stonger setup using universal joints as apposed to the rubber donuts.
 

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Kepler said:
I am now in the process of installing an earlier model tail shaft which ironically was a much stonger setup using universal joints as apposed to the rubber donuts.
It is all about the factory trying to reduce NVH. I have a 2000 model Commodore with the earlier driveshaft. There is still a rubber donut just behind the transmission (M6), but I believe it will take a bit of stick than the new one. I have just had the original donut replaced after 20000 miles and it was replaced with a revised (read beefed up) part.

Mick
 

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Discussion Starter #20
Here are the time slips as promised above.

DY - I agree, something has to be done about that driveshaft before the 60 ft/times get any quicker. They will probably survive for a while on an automatic but the M6 cars are much harder on them.
 
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