Competition Need faster 1/4 mile

[diesel4power]

Ive been bombing my truck since I got it last July and the other day a friend lent me his new G-tech performance meter. I was a little dissapointed that the best I could do was a 15. 31 1/4 @ 93. 8mph. The most boost I can build for take off is 10-12 lbs, the converter is so tight that if you put your foot down any it just wants to stall. When you let off the brake the truck seems to linger before it gets going. If I only let the engine rev a little and get hardely any boost it seems to take off much faster, even breaks the tires loose.

Am I doing something wrong? I have mach 2's on order and the TST box is going back to be reflashed to make it a comp. Both these upgrades should give me an extra 100 horse or so. My goal is to be in the 13's. Am I going down the right path?



What do you all think?



Paul

 

[GO 4LO]

Take it out to Edgewater or TriCounty sometime and try it on an actual track. Track surfaces are prepped better than the street surface you were using with the G-tech. Also, I think the G-tech measures your actual speed at the end of the quarter mile, while the track uses an average speed over the last 60 feet of track. So the G-tech trap speeds are a little inflated.

Chris

 

[GO 4LO]

Oh, and with regards to the power, I'm not too experienced, but I'd guess that would put you at about 450 hp, maybe 1050 ft-lbs torque? Probably around 14 flat at 96 or so with an automatic and a decent launch. That's a guess - somebody more experienced can probably give you better data. Hope that helps.

Chris

 

[CumminFast]

I think the hp would be about 350 w/ 275s and that hx35.

 

[GO 4LO]

Originally posted by CumminFast

I think the hp would be about 350 w/ 275s and that hx35.

What about with the Mach 2's and 35/40 hybrid? Also, do you have any pics of the truck in your sig on 38" Michelins? Sounds nice .

Chris

 

[StakeMan]

You are probably defueling.



Check out the BD R. A. D.

 

[DavidTD]

I was gonna guess 380hp with the Hybrid. 275's and FMS with timing box or 275's and a comp usually come in around 350 or so.



I don't know about the mach 2's but I am sure they will deliver what Don says they will. I've seen a comp with Bully Dog IV's make 425hp with a stock 35.

 

[banshee]

I agree with stakeman. The stalling you're feeling is the ECM defueling because of the torque management system. If you want really hard launches you need the BD R. A. D. box... it's well worth the money!



John

 

[DavidTD]

Originally posted by banshee

I agree with stakeman. The stalling you're feeling is the ECM defueling because of the torque management system. If you want really hard launches you need the BD R. A. D. box... it's well worth the money!



John

I think you are both right. Something I didn't even think about.

 

[diesel4power]

OK I understand the defueling could be an issue at launch but why am I strugling to get 10-12 lbs of boost. 10lbs is all I can really hold, just anymore on the gas and the engine bogs down and boost drops off to 5-7 lbs.

 

[banshee]

The ECM will defuel you while building boost as well as after you launch. The computer knows you have 10 lbs of boost, it knows the RPM, and it knows you're not going anywhere. In order to save the transmission (not the ATS... the stock one) it cuts the fuel back. Some trucks seem to be worse than others, and yours sounds like one of the worse ones. My 01. 5 would keep building boost over 10 lbs but wouldn't go any faster off the line with more than 8. My Dad's 02 will do almost exactly the same thing as yours without the BD RAD box. Also, with the box on my 01, I cut almost 1/2 a second off my 1/4 mile ET. It sucks the ECMs do it, but BD has the hot ticket.



John

 

[snowracer69]

Mine is a 2001. 5 and i also have the same problem. It will only build 10-13 lbs of boost and even after launch it stalls. I know the BD Rad box will cure it but i have talked to a lot of people after they install the box they break their output shaft. That is why i have not bought one yet.



Denis

 

[StakeMan]

Shaft breakage can happen if you don't keep the boost reasonable at the line.



Instead of the ECM defueling its up to your right foot.



I keep the boost under 20 psi because I still have my factory shafts and would like to keep it that way for a while.

 

[dlange]

I have the same problem. But mine defuels at 9 and is sluggish on the 1-2. But even leaving with 5 lbs of boost I'm hitting 104. 9 mph. I wish I had the RAD to she what she'll really run. -Dave

 

[diesel4power]

All the talk about breaking shafts with the BD RAD. Is this only the case when launching in 4X4 or can it happen on a 2 wheel drive launch? I thought the TST box would override the ECM as far as fueling and defueling goes?. So am I right in thinking that the BD RAD is only going to help launch faster when building boost and give me a faster 1/4 mile time, nothing more nothing less.



Paul

 

[StakeMan]

Originally posted by diesel4power

All the talk about breaking shafts with the BD RAD. Is this only the case when launching in 4X4 or can it happen on a 2 wheel drive launch? I thought the TST box would override the ECM as far as fueling and defueling goes?. So am I right in thinking that the BD RAD is only going to help launch faster when building boost and give me a faster 1/4 mile time, nothing more nothing less.



Paul

I think it could happen to either 2 or 4 wheel drive launches. Chances are that a 2wd will loose traction first before a shaft.



TST over fuels to make up for the defuel above 2700 rpm. BD RAD fixes the defuel on launch or when ever torque management comes into play.



IMO the only use for the RAD box is racing.