95' Junker Drag Truck

You are right tires are the deal but with the wieght racked forward it's fighting to get the wieght shifted to the rear. With street tires I'm guessing it can't hook hard enough to even tranfer any wieght. Might be time to find a diesel tank to put in place of the spare tire and move the batteries to the rear of the bed. Anything to get the over three thousand lb. front lighter would help.

Do you think the 28cm housing is the smallest made for the ht4b?
 
gwhammy said:
You are right tires are the deal but with the wieght racked forward it's fighting to get the wieght shifted to the rear. With street tires I'm guessing it can't hook hard enough to even tranfer any wieght. Might be time to find a diesel tank to put in place of the spare tire and move the batteries to the rear of the bed. Anything to get the over three thousand lb. front lighter would help.

Do you think the 28cm housing is the smallest made for the ht4b?
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I'm not sure what's available. The turbine wheel measures 118mm x 88mm. I'll bet a machinist could make a smaller housing fit pretty easy assuming an HT3B housing could be opened up that much.
 
JQmile said:
Cool, good luck! I'd love to see an 1.7 or 1.8 60ft ;) I know you would too....
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I was digging through my old time slips from last year and I was shocked to learn that I cut 1.90 second 60' time on my 12.35 pass in Wittmann, AZ with those cheap Nascar road race 27x10 slicks. If the track ends up with similar grip/prep this year, I'd imagine I could cut a few 1.8x 60' times with the real drag slicks.
 
I wasn't really even paying attention to the time on the clip itself, as in how long you spent staging, but did you even get to stage at all? How much boost do you leave with? The very first video looked like it was almost a rolling start haha. Against the Mustang you looked like it staged much more and you ran a much better time. I mean I could just be seeing things but who knows!
 
USARMY12V said:
I wasn't really even paying attention to the time on the clip itself, as in how long you spent staging, but did you even get to stage at all? How much boost do you leave with? The very first video looked like it was almost a rolling start haha. Against the Mustang you looked like it staged much more and you ran a much better time. I mean I could just be seeing things but who knows!
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The 13.8 run was the first pass since breaking the driver's side axle so I planned to take it easy and leave soft. I left at just above an idle, no boost registering on the gauge. On that pass I had to lift after every gear shift and twice in second gear to regain traction. It is not common for 12 second vehicles to lose traction at 80 MPH on the 3-4 gear shift, but it happens when the conditions are slick and you're driving a front heavy diesel with street tires!

The 12.8 run was my second pass and I left pretty soft, maybe 2-3 psi boost because I knew the track wouldn't hold a real launch with street tires. It's hard to tell in the video's how many times I get on and off the throttle, but it's more than three times during that run.

With the nascar slicks, I can usually launch with about 5 psi. I have had it hook up once or twice with 7-8 psi but then it blows the tires off about 30 ' out because it comes up to full power too early in the run and overpowers the chassis/traction setup.


The main purpose of running last friday night was to make sure the truck drove straight and handled well at speed, and work on my SLOW reaction times. If all goes as planned, I'll try out the slicks next Friday.
 
I think once it gets a bit warmer out to make the track a little stickier you'll see a massive improvement. Especially with the new rubber!
 
Update

Added some ballast to the right rear corner of the bed. I had 120# worth of scrap steel laying around so I bolted it down with a couple 1/2" grade 8 bolts to remain NHRA compliant.

Ballast1.jpg


Ballast2.jpg


Ballast3.jpg



With the new ballast, I decided to hit up the track and try to sneak in with my slicks. I went for the more "road worthy" stiffer sidewall 27x10" road race slicks mounted on steel 15x10" rims.

First run of the night, I left soft and ran 12.365 @ 113.06 MPH. Two weeks ago with nothing changed other than 120# not yet installed and running 33" mud tires, I ran numerous trap speeds in the 117-118.5 MPH range. I have narrowed down the problem to fuel lift pump pressure. My cobbled together lift pump system cannot maintain adequate pressure. In fact, around 1000' out, boost starts a steady decline from 85 psi to 65-70 psi range at the stripe. Truck noses over and clearly runs out of fuel once RPM approaches 3000. With 27" tires, I'm turning close to 3500 rpm at the stripe hence the soft back half of the track.

Nonetheless, I went for another run and left with a few lbs of boost 4-5 psi.

Finally after almost 1 full year of fighting traction, the combination hooked up:

11.956 @ 113.27 MPH

1.976 - 60'
5.154 - 330'
7.743 @ 95.58 MPH 1/8th mile
9.991 - 1000'
11.956 @ 113.27

I can only guess that it would have gone a tenth or two quicker if I had adequate lift pump pressure and would have probably trapped in the 122-123 MPH range.

22412Timeslip1195.jpg



Timeslip1195.jpg


I then made another pass and ended up with a little wheel spin off the line and ran:
12.015 @ 113.05

My camera operator was ready for this pass and shot the run:

[ame="http://www.youtube.com/watch?v=G3UTpASsHI4"]http://www.youtube.com/watch?v=G3UTpASsHI4[/ame]

All in all, I made 9 passes ranging from 11.95 to 12.79.

Nice close race with a local Dmax:

[ame="http://www.youtube.com/watch?v=uDVG0e36MLQ"]http://www.youtube.com/watch?v=uDVG0e36MLQ[/ame]

[ame="http://www.youtube.com/watch?v=35PbjeAvrFk"]http://www.youtube.com/watch?v=35PbjeAvrFk[/ame]

[ame="http://www.youtube.com/watch?v=Jbm-Kig9lZg"]http://www.youtube.com/watch?v=Jbm-Kig9lZg[/ame]

[ame="http://www.youtube.com/watch?v=sMtqJNyPhJ0"]http://www.youtube.com/watch?v=sMtqJNyPhJ0[/ame]

[ame="http://www.youtube.com/watch?v=7BLIPnJVPnk"]http://www.youtube.com/watch?v=7BLIPnJVPnk[/ame]
 
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That has to feel good man! Congrats!

And once you get the FP figured out it should be fairly easy to run QD!
 
RJM06590 said:
Nice man, what are you going to do about pressure?
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I was offered a great deal from one of the lift pump companies in the diesel performance industry, however, I still couldn't swing the $$$.


So I ordered a $100 Walbro 392 fuel pump. The plan is to install another pick-up tube and run the Walbro as a stand alone fuel system triggered by a toggle switch, filtered through a separate used factory fuel filter base, and fed to the front 18x1.5 port on the P7100 injection pump. Based off of Walbro's flow chart, at my target 80 psi range, it should still flow enough GPH to maintain pressure when all (3) lift pumps are running: (1) Procomp Black feeding 14 psi, into (1) stock mechanical pump feeding the factory filter and pump feed, and the (1) planned upgrade of Walbro 392 feeding front pump port.

gsl392rd0.jpg
 
Makes sense, there's a third port on the side of the pump if you want three pumps. :D
 
Big Blue24 said:
I was offered a great deal from one of the lift pump companies in the diesel performance industry, however, I still couldn't swing the $$$.


So I ordered a $100 Walbro 392 fuel pump. The plan is to install another pick-up tube and run the Walbro as a stand alone fuel system triggered by a toggle switch, filtered through a separate used factory fuel filter base, and fed to the front 18x1.5 port on the P7100 injection pump. Based off of Walbro's flow chart, at my target 80 psi range, it should still flow enough GPH to maintain pressure when all (3) lift pumps are running: (1) Procomp Black feeding 14 psi, into (1) stock mechanical pump feeding the factory filter and pump feed, and the (1) planned upgrade of Walbro 392 feeding front pump port.

gsl392rd0.jpg
Click to expand...
I was gonna recommend a walbro. You could run 2 pumps for a lot less than anything avaliable .
 
Maybe trigger it off of a adjustable pressure switch off of boost.That way it would be off when not needed and you won't forget to turn it on. Just a thought.

Bsmith might be right, run two and do away with all the stock stuff. A good fuel filter base is one off of the old 7.3s or 6.9s. You can cross a big wix filter on them.
 
gwhammy said:
Maybe trigger it off of a adjustable pressure switch off of boost.That way it would be off when not needed and you won't forget to turn it on. Just a thought.

Bsmith might be right, run two and do away with all the stock stuff. A good fuel filter base is one off of the old 7.3s or 6.9s. You can cross a big wix filter on them.
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I have a regulator on my return that's referenced off boost, 40psi @ idle and goes up with boost.
 
congrats on the build ... everytime I see this thread I tell my self I should have built a drag truck
 
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