95' Junker Drag Truck

Update: Went to the track tonight, it was pretty cold, upper 50's so great air for making horsepower.

The only modification since last time is the addition of a procomp black pump running through 3/8" fuel line feeding the stock mechanical lift pump with 12 psi of fuel pressure. Wide open, fuel pressure now drops to about 38 psi, whereas before fuel pressure would drop to less than 10 psi.

I ran a new personal best 12.724 @ 111.98 MPH
I backed up the run with a 12.80 @ 112.07 MPH.

TimeSlip001.jpg


TimeSlip002.jpg

The printer at the track jambed up for a few minutes during this run so I had to go to the tower and get the time break down.


The new MPH calculates to 525 rear wheel horse power for a net gain of 83 HP. Just adding a pusher lift pump added 83 HP, who would have thought!

Also, a huge thanks goes out to Phil Taylor of Diesel Performance Converters. The custom stall he developed for this truck is awesome in the cooler weather. It spools up in about 5-7 seconds at the line and pulls hard through the run. As much as I hate to admit it, this billet single is holding up great and locks up firm.

One last thing, the scale was turned on at the track and I spent a few minutes weighing the truck. Without driver, the Junker's weight ratio is 64% front 36% rear with an overall weight of about 5220 lbs.
 
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Here is my time slip for me truck wanted to get them closer for easyer comparison
 
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Where is the other time slip Cliff? The faster one... You know we really just need to re-work the suspension then spray the chit out of it off the line. 2.2 60'? No more!

I saw we because I need a vacation, like I say every week I'm at work. Not that I'll be much help... Last time it took two hours for me to unlock the shop to get a fuel plate. LOL
 
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Its in the truck some where lol ill find it I'm more comparing the 1/8th on time gain wise. I need slicks and supension yes I know lol. Looks like we olny have a tenth or two difference in the top end with us both gaining about 22 mph . Blue is your truck still smokeing going down the track? Mine will clean up all the way with the n2o but my factory lift pump is killin me above 2800 rpm.
 
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Lostnwalmart said:
Its in the truck some where lol ill find it I'm more comparing the 1/8th on time gain wise. I need slicks and supension yes I know lol. Looks like we olny have a tenth or two difference in the top end. Blue is your truck still smokeing going down the track? Mine will clean up all the way with the n2o but my factory lift pump is killin me above 2800 rpm.
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Which gsk do you have?
 
Lostnwalmart said:
Its in the truck some where lol ill find it I'm more comparing the 1/8th on time gain wise. I need slicks and supension yes I know lol. Looks like we olny have a tenth or two difference in the top end with us both gaining about 22 mph . Blue is your truck still smokeing going down the track? Mine will clean up all the way with the n2o but my factory lift pump is killin me above 2800 rpm.
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As far as smoke, on a scale of 1 to 10, 1 being stock clean and 10 being coal black, its about a 7 running down the track wastegated at 38 psi and about a 6 with the wastegate pinched running about 50 psi boost.


And just an interesting little tidbit, the best MPH with the internal wastegate set to 38 psi was 109.7 MPH vs pinched wastegate making 50 psi was 112.07 MPH. This turbo has a large 1.28 AR wastegated T-6 housing so I'll bet it will run even faster with 55 psi boost, just needs more fuel!

One more thing, on my last run, I lost a siliconeintakes.com boot. It was a 3.5" to 3" 90* bending reducer that connected the GT42's outlet to the stock charge pipe. The silicone boot blew about 20 feet before the stripe on my 12.80 pass. I looked down at the boost gauge several times during the run and it was definitely running right at 50 psi.

Directly from silicone intake's website:
Genuine 4-ply Silicone (5 silicone layers plus 4 reinforcement layers = 9 total layers!)
Installer can cut silicone parts down to fit with a razor
Heat tolerance: -40° to 392° Fahrenheit
Burst Pressure: 200 PSI
Working Pressure: 50 PSI
Wall Size: 4 mm - 5 mm

Anyway, I put two layers of duct tape over the torn boot and drove home. I was surprised at the fact that I could maintain 60-65 MPH on flat ground running essentially naturally aspirated. I could hear the duct tape squeal and hiss if I made even 1 psi boost. Long story short, I will not make it to the Friday night drags this weekend.

I could always bolt up the stock turbo and torture it but I'm afraid with my current fueling, I would be able to melt the turbine wheel and possibly send aluminum compressor wheel fragments into the motor.
 
I'm hitting (rough gustamate) 65 to 75 paid with my set up. Put some more boost to her! And see what she will do:rockwoot:
 
Im not sure how they rate those but it could of blown cause of the extra stress from being a 90 and a reducer causing more pressure. If they just rated the material and not the actual part this could be true.
 
SSpeeDEMONSS said:
also, how hot did that boot get?

Garrett
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The outside air temp on that run was about 55*F. 50 psi boost is off the compressor map a little so it would be difficult to make an accurate guess on turbo outlet temperature. I would guess outlet temp was really close to the 392*F rated limit from the manufacturer. The boot did last 2 other full passes at 50 psi and several passes at 36-45 psi. I can buy another boot for $19.99 and add about $2 worth of duct tape and tie wire and I'm sure it will hold up to 70 psi.
 
Pictures of the torn boot:

Boot001.jpg

Boot002.jpg



I was told the exploding boot sounded like a nitrous backfire back in the grandstands. The boot blew really close to the finish line so it wasn't really loud for the spectators.
 
I would recommend a cast or fabricated elbow, and then use silicone for the straight shots. They seem to hold up a lot better then the 90's. As well as mechanical links so the boot only has to hold pressure, and not the pulling force of the piping trying to separate.

What are you doing for rear suspension? Any traction bars?
 
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dvst8r said:
I would recommend a cast or fabricated elbow, and then use silicone for the straight shots. They seem to hold up a lot better then the 90's. As well as mechanical links so the boot only has to hold pressure, and not the pulling force of the piping trying to separate.

What are you doing for rear suspension? Any traction bars?
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For the rears, I have homemade caltracs built out of Harbor Freight tractor links. I'm still working on getting the suspension dialed in because I should be able to consistently run sub 2.0 second 60' times with these 10" wide road racing slicks but so far I'm usually running about 2.15 to 2.25. On my best pass, I did get a 2.0 60' time which helped a ton on the overall ET.

As far as elbow, I agree that cast or steel would be better. I plan to buy another 19.99 silicone elbow and reinforce it with duct tape.
 
dvst8r said:
I would recommend a cast or fabricated elbow, and then use silicone for the straight shots. They seem to hold up a lot better then the 90's. As well as mechanical links so the boot only has to hold pressure, and not the pulling force of the piping trying to separate.
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This is the only way I could get mine to hold. Mine goes reducer welded to the 90 welded to a straight piece, then some tractor trailer water hose instead of the silicone. It holds 65 no prob.
 
Big Blue24 said:
For the rears, I have homemade caltracs built out of Harbor Freight tractor links. I'm still working on getting the suspension dialed in because I should be able to consistently run sub 2.0 second 60' times with these 10" wide road racing slicks but so far I'm usually running about 2.15 to 2.25. On my best pass, I did get a 2.0 60' time which helped a ton on the overall ET.

As far as elbow, I agree that cast or steel would be better. I plan to buy another 19.99 silicone elbow and reinforce it with duct tape.
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Might not be much more money to find a cast 90 aluminum elbow, and stop by a local fab shop with a case of beer the elbow and the compressor cover and get them to weld it on. Just a thought anyway.

As far as the rear suspension. Are you still running all the stock leaves? Probably should take out just about all but the main leaf. Don't need to get it to carry any weight any more, but you do need it to transfer weight back there. What about shocks what are you running for shocks?
 
i had a similar boot from siliconeintakes.com , it was a 2.75-3" 90 degree , and it split extactly the same as yours did.
 
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