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Let me tell you .......hurricanes are not all bad. My friend from the land of fruits and nuts (????) decided it would be better to leave norfolk Va(there for work) and visit His friend in Alabama than ride out the storm. We shared some good ole dreamland barbque and a great evening at the drag strip. We stacked and tried everything. Here are the results. All runs were made in 4 hi with approximately 5-8 psi of boost.

We got a little carried away and forgot to make a run with just the stealth.(sorry Quad)

However the stealth and the tst on level o and 6 te yeilded a 8.852.

The same stack on level 1 and te 6 yielded a 8.623.

The same stack on level 1 and te 6 plus propane yeilded a 8.617.


Then we stacked the comp juice and the stealth 215 this yeilded 8.539.

The final run of the evening was my 02 duramax vs a 03 ford cobra 32 valve supercharged and here is the time sheet. For this run we stacked comp juice with the stealth 215 and a healthy shot of propane.




My duramax time was on the left
Needless to say the guy in the mustang got his feelings hurt....the names at the top of the slip were on all slips they were the guys runnning the test and tune nite.

The motor was as quiet or as quieter than stock with this stack and the suncoast tranny handled all of this power without missing a beat. What a great testiment to joe's work at suncoast. The weight of the truck and driver was approx 7250lbs(no tail gate or spare)
Dave
 

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I am not too firmiliar with 1/8 mile times. Do you have any idea how these times would be reflected as 1/4 mile times? We do not have an 1/8 mile track around here.
 

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Nice! Sounded like fun.
 

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That would be around a 13.1 1/4 mile run.
 

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Amric


The standard conversion for 1/8 times to 1/4 mile times is as follows


1/8mile ET/.64= 1/4 mile ET





8.392/.64 = 13.1125
 

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I don't know if the standard conversion would work here. but I guess it's pretty close. He has been cutting some 1.6 sec 60 ft times and that's pretty darn quick for a 13 sec 1/4 isn't it? Then again he has the aerodynamics of a brick to deal with also
 

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a64pilot


The conversion's are all based upon cars so all they do is get you in the ballpark. Last night we were out at our local 1/8 mile track and ran 7.945 @ 87.34 in our Duramax. So that figures to a 12.414 1/4 mile but when I compared our times with a freind's Dodge we ran almost identical 1/8 mile times to his 12.15 1/4 mile runs. Do I think we will run 12.15 or 12.414? Until you get it down the track noone every truely knows!
 

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At 7.9 you could be close to a 12.1 since you are in 2wd and fairly light. In a 4x4 CC 7.9 is more like a 12.40-12.50. This is just from what we have seen. Also 1/8 mile doesn't allow you to make up for bad 60' times like a 1/4 mile does.





QUad
 

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Quad


Since we have added 500 lbs and seen no change in our times your argument about 2 wd and lite is bunk! The 4wd guys run 1.6 - 1.7 60' times and our best to date is 1.826. The difference in weight is more than made up by the advantage the 4wd gets you in the 60' times! Leaving the line at 8 - 10 psi (4wd) Vs 3 - 4(2wd) is huge in the 1/4 mile! Also the Dodge we compared to is a 4wd so I guess that means we should be running 11.8x by your numbers. Not bad for just a computer tune, exhaust and tires
 

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The traction of a 4x4 launch would help a great deal in the 1/8 mile, but the weight of the 4x4 would hurt in the 1/4. So with that said, the 4x2 should be able to make up a lot of ground in the 2nd 1/8 mile of a 1/4 mile run.


Not only does a 4x4 weigh several hundred pounds more then a 4x2, it will have a whole lot more drag if 4 wheel drive is being used. And on top of that, the 4x4 will need lots more power to power 4 tires instead of just 2.
 

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Hdmax


I disagree with your logic from the standpoint that, what we have done is added 500 lbs to the 2 wd truck and raced the exact same times as without the weight in the truck at the 1/4 mile track! The 500 lbs is the difference between a 4wd and 2wd. I agree that it takes more to turn the 4wd than the 2wd but I feel the advantage of the 4wd in the first 60' and the higher boost more than makes up for the losses in the 4wd.


Consider this, our 2wd suffers from bad wheel spin if we try to launch with more than 3 - 4 psi, so we have to make the boost as we go down the track. A 4wd on the other hand leaves at 8 - 10 psi and is upto full boost much sooner. Now if we can get the wheel spin out of the 2wd and launch at 8 - 10 psi like the 4wd guys I feel there will be and advantage to the 2wd but were not there yet. Right now our truck feels like a low to mid 12 sec ride but until we have the time slips to prove it, it's just bench racing. Current best 1/4 mile is 12.78 and current best 1/8 mile is 7.94.
 

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Unless the 500 lbs is giving you better starting traction, it will slow you down. 500 lbs is 500lbs. More weight will always slow the vehicle down if the power stays the same, unless traction changes. (which with a 4x2 that just might be the answer)
 

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I think you've missed my point, we added the weight and saw no difference in times. What that tells me is that we have more than enough power to pull the additional weight but that we cannot get the traction to get it moving. So by launching softer and rolling into it cost us more than the losses in a 4wd. Since the motor is going through the lights at 3400 - 3500 it's about all done at that point. The internal backpressure at those RPM's is quite high and rising quicker than the intake pressure. To run higher RPM's we need to replace the turbine housing to lower the internal backpressure numbers but right now we are doing everything on a stock truck. After we've finished with this we may modify things like the air cleaner, turbo and add some NOS. Then it becomes a modified truck and we will see where we can get with that.
 

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don't forget a 4wd truck has more hp loss thru the transfer case, front axle and front wheels There's more to it than just the extra weight. With the same hp and weight a 4wd truck will have a slower mph than a 2wd truck but the 4wd truck will have a better 60' time than the 2wd truck.
 

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Come on everyone lets take up a collection for Steve so he can buy a 4x4 and quit whining.
 

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I launch at idle. 0 psi of boost. I avg 1.95 60's If I lauch harder I can cut 1.8x's, but I break about every third pass. I have too much power to launch.


If you add 500 lbs and run the same times you are doing something wrong? I can see a variation in et with minor changes and it is consistent. I can remove the spare tire and tailgate, or run with different weight of fuel and I can see et cahnges every time. Maybe not huge differences, but it does change.


I am not just in 4x4. I am on 285/75/18's in a 4dr with all the options. I have no idea what it weighs and I don't care. If I weigh more I simply need more power to go faster than a lighter truck. The truck we use is like the majority of everyone elses trucks. It is driven daily, its comfortable, I tow our campers with it, and I can haul several people with me. I have no idea what your truck is and it doesn't matter, but weight is weight. Also teh more options you have the more weight you get. It is small but again weight is weight.


Now 4x4 has an advantage off the line in most cases, but not always. I have no desire to run slicks on my daily driver. In 2wd the truck is not manageable. If we ever get the suspension right, yes then we should have an advatage in the first 60'.


Now from 60; foward there is less mass in motion on a 2wd. In 2wd you should always get more mph. I saw an example of 1 mph for some. WE can run 3 mph faster in 2wd and almost 1 sec slower. Maybe your truck is different but I think you will find across the board give the same power and the same 60' a 2wd will always be faster. It takes more power to move more weight, especially when you have double the rotating mass.


I am not a drag racing expert, but I have made a few passes and done a little bit of testing. I also have a small amount of experience racing other forms as well.


All in all if you are in the 12's you are doing great in a diesel. A couple of years ago it was almost impossible. Technology is definately catching up and the trucks will go faster and faster.


I would kill for 1.6x 60' times right now.
 

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Cpmac


I'm not whining just stating the facts!


Our truck varys about .1 sec run to run so if it's within that window I call it a wash. Our 12.78 run was with 7/8 tank of fuel and the truck had everything in place, spare tire, tailgate, laptop computer, Tech II, tools ect. on ET street tires with the additional weight we ran 12.85. The truck is fully loaded with options except leather interior and it's used as a work truck every day, towing ,hauling or what ever is needed.


"especially when you have double the rotating mass"


I donot know how you figured this but your wrong.


"I would kill for 1.6x 60' times right now."


You and some of the rest of us too!


The main reason for drag racing the truck is to put the transmission and converter upgrade through more abuse than most people would ever do in a lifetime. It proves out our products and sometimes shows what needs to be modified the hard way!
 
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