Competition Whats the highest boost you guys launch at?

[J.Davy]

I did a boosted launch at about 15 pounds the other day by accident I usually don't go above 10,and I spun all for tires. I couldn't believe it ,the front tires walked out to right ,I was preety impressed. What is the max you can go if you have the billet shafts?

 

[Rhondasway]

I assume you have all the proper equipment (billet input/output), got loops in case you lose a Ujoint? This leads me to a sidebar question: has anybody ever lost a front Ujoint dragracing?

What you can launch at depends mostly on what your rubber is, how sticky the track is (are they using VHT). I personally have never been able to hold traction at launch with more than 20lbs, and usually can only hold at 18lbs or less. I run M&S 265/75/16's, so a more aggressive, wider tire may hook better. Burnoffs don't seem to help my truck, but may help yours (they're so fun I do them unless seriously bracket racing anyway). Also, you're only spinning 3 unless you have a locker, but it is pretty damn cool nonetheless. I love that sideways lurching, accompanied by that aggressive chirping sound. Drives the crowd WILD! Oo.

You should experiment, as it is also possible to lose traction that you don't quite notice. Make sure you know exactly where you're staging, and watch your 60' times; they'll tell you everything.

 

[COMP461]

80 to 90 psi



and Rhonda your welcome to slide in to my truck, I need a weight reduction

 

[Green Machine]

About 12lb's is all the higher I can go, then the clutch slips or the tires spin...

 

[J.Davy]

Is ther a special technique to steadying the boost ?I have only launched while I was watching the boost gauge and waiting for it to hit the desired number ,but I can't imagine doing this while staging and watching the lights all at the same time. It would be nice to have some sort of switch you could flick to bring you up to a predetermined boost number. Comp,do your guys trucks that run in that class have some sort of clutch in the transmission to control slip?I am assuming your truck is 2 wheel drive?

 

[Rhondasway]

With my mechanical setup I've been battling that from the beginning. It is indeed very difficult to light that first bulb, build and steady the correct boost, stage perfectly (these monsters don't like to inch forward), then wait for the tree. The Pro (car) racers I run against have told me not to launch with boost, because it is so difficult to be accurate round after round, when dial time is everything. They are right, but I cope because I like to go fast. A good racer who knows what your routine is can eat you alive, as you can only hold that much boost for so long. This is made more difficult if you have to use a boost gauge that accomodate twins; they don't show low boost very well...

If, however, you're just running for quickest ET, there's a lot less pressure.

I would think with the growing popularity of diesel power, someone would develop a trans brake or some such item. Until then, it's all finesse (as far as I know).

' Luck

 

[DRAG DIESEL]

I would think with the growing popularity of diesel power, someone would develop a trans brake or some such item.

RR,

there is.

 

[CUMINNTSTRKN]

With the full billet dtt transission I have launched at 50psi. I have arb lockers front and rear and it was searching for traction for the 1st 20-30 feet. I have done this a couple of times becuase opie and bill said these shafts were tough, they were right. As far as launching while racing 20-30psi seems about perfect for me.



Jim

 

[WCounts]

I launch at 10 psi. This is all it takes for my turbo to spool instantly. To bring the boost up prestaged and inch up on the staged light can get tricky. Most operators will give the diesels time to come up to boost.



Lets go racing

 

[powerwagon440]

last time i was at the track i did a 30psi and i was just trying for 20psi i couldnt hold her. and i red lighted and about jumped the outside 2ft high concreate wall. if i ever get it back together again i need some practice sure made a few hundred people a beleiver in diesel performace on that day :-laf

 

[Rhondasway]

With the full billet dtt transission I have launched at 50psi. I have arb lockers front and rear and it was searching for traction for the 1st 20-30 feet. I have done this a couple of times becuase opie and bill said these shafts were tough, they were right. As far as launching while racing 20-30psi seems about perfect for me.



Jim

Aaaah, Mr. Fuller, I'd forgotten about your high-boost launches. I have locker envy...

Mind if I ask what your best 60' time has been? And at what boost? I would also like to know what your best 1/4 ET is. You have one bad rig (with many trick components)! Any chance we're going to see you at some races this year?

 

[nascar mark]

80 to 90 psi

Ya right. It's getting a little tiring.

 

[CUMINNTSTRKN]

Rhonda i'm not sure if I will be able to make it out this year, or even if I will do much racing.



I need to get out there and at give her all she's got now that the transmission will hold it.



Jim

 

[TractorNut]

Rhonda, anyone looked at putting a big Pressure gauge either on the hood or on the dash. . and have it mobile so you could move it so will be close to being in line with the lights. . Just a thought... .

Bryan

 

[COMP461]

How else do you think I 60' 1. 18

 

[CMNS PWR]

How else do you think I 60' 1. 18

Fudge the numbers? Dyslexia?

 

[nascar mark]

How else do you think I 60' 1. 18

Light truck and big full racing slicks will do that but not with 80-90psi !!! You expect anyone to believe you launch with the same amount of boost you claim your truck makes going full out down the track?

 

[COMP461]

Well yes , that’s what I do, I leave at full throttle, the motor goes to full boost with in . 25 of second once I smack it on the line , and the boost is at 85 to 90 PSI when I let fly of the trigger . which is usual about 4000 + rpm’s . Why would you not think that is what I do . when I am not running NHRA and allowed a Nitrous bottle in the truck, which was not in the truck during the record run, I turn on the first stage , at full throat, even before I leave , the second stage comes on when I let fly of the button . I will be running the NHRA divisional race at Dallas , in two weeks , we are moving the truck up to TOP Sportsman ,

 

[sbentz]

I would think with the growing popularity of diesel power, someone would develop a trans brake or some such item. Until then, it's all finesse (as far as I know).

' Luck

RR,

there is.

Hmmm... Must be that top secret purple transmission that someone has in a dragster.



As to what boost we launch at? Depends. Dustin has left from 15 to 30 PSI depending on the situation. For us, we have not used the full throttle launch yet. No reason to unless we were trying to break an input shaft. Now with the new trans, we can.



Gee, I wonder what that will do to the 60' times and ET?

 

[Rhondasway]

Jim, I hope you can at least make it to Diesel Thunder in Spokane. It would be a shame not to use such a well set-up truck; I was thinking how much I need a dedicated race truck, so why don't you just sponsor me and let me pull it behind the Princess for this season... lol...

Bryan, that hood gauge has been talked about and could help some, but really it's more a matter of steadying the throttle. This is hard when your second turbo (or big half of large single) is trying to kick in. First you're pushing through lag, then you have to ease off, but just enough to keep it from shooting up. Then you've got to creep into the second light, and even with very good brakes it wants to leap forward. You sure develop an ear for RPM...

When racing at truck/diesel events, the starters seem to take all this into account and are forgiving (except at last year's Truckfest in Denver, where the starters seemed to be studying astrology or something ). However, at a points event when running against cars, it's pretty easy to time-out and get an automatic red light. Not to mention that it's very hard to be consistent on where exactly you're staged, therefore totally affecting your R/T's and dial accuracy.

'Course, if it were easy, who'd want to do it? :-laf