95' Junker Drag Truck
- Thread starter Big Blue24
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Big Blue24
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If my truck was a 4x4, and the same weight and horsepower.... big IF....
Assuming a good average 60' time of 1.75 seconds, and 1/8th MPH of 95.6 MPH,
it would be capable of 11.48 @ 122 MPH.
If my truck was a 4x4, it would have enough traction to leave with 10-15 psi boost so it would be able to put down more average horsepower throughout a 1/4 mile run. Therefore, it would probably run a little quicker than 11.48. But, there is no way a 4x4 will be as light as the 2wd, so the 11.48 guesstimate is probably accurate.
USARMY12V
Rally round the Virginian
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I was guessing a half second difference so I was close I suppose. Weight difference is a big issue in the equation, you're right. I wonder if your guessed 4x4 60' would be even better than that with your stickies you run. Do you think some adjustable shocks would help your truck plant better?
RJM06590
What to do
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On the side behind the throttle linkage.
Big Blue24
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The guys that race their 4x4's at the strip and actually tune the suspension are doing much better that 1.75 60' times. Most are in the 1.55 to 1.7 range for 60' times, which makes a huge positive impact on the ET they run.
USARMY12V
Rally round the Virginian
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Yeah I assumed as much. I can only imagine how much work you've done, even outside of what's in this thread with calculations and stuff to get it to hook as well as it does. My truck with considerably less power (and more weight) can almost spin in a straight line on the street when launched with any amount of boost. Keep up the good work man. Very interesting thread to say the least.
Big Blue24
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I started installing my 3rd lift pump which is going to be a complete stand-alone lift pump system that will feed the front port on the p7100 injection pump. I wasted most of my free time on Saturday removing the blasted front port plug and ended up using the welder to get the job done.
The fitting is a metric 18x1.5 to JIC 8 adapter, then a standard JIC 8 90* pushlock fitting.
This is a side view to show how far forward the fitting protrudes into the fan area, as you can see, there is plenty of room.
I also added another fuel pick-up tube at the stock plastic fuel tank. The front pick-up is for my added Holley Black 140 GPH knock-off pump that feeds the stock mechanical lift pump. The newly added rear pick-up tube is for the new standalone fuel system that will utilize a single Walbro GSL-392 pump, capable of around 50 GPH at my target PSI range of 65-85 psi. The advantage of the Walbro is it's capable of almost 120 psi by itself so no need to run staged pumps, just single pump and filter setup. Also, the Walbro 392 255LPH High pressure pump is relatively inexpensive at around $100. The Walbro pumps are not designed to run on diesel fuel, however, they do still last a few years and I'm only running it at the track since the stock lift pump makes plenty of power for street use.
Here is the whole system laid out on the work bench. It'll run with 1/2" line to my 1/2-3/8" reducer, then a short run of 3/8" into the Walbro pump itself. Then 3/8" outlet from the pump all the way to used stock fuel canister I picked up for about $15-20. Then 1/2" from the stock filter to a 1/2" check valve and then 1/2" on into the front feed port on the pump. I used the mismatched line sizes because I had several 1/2" parts laying around in my spare parts bin. The 3/8" is required at the Walbro pump so that's why the line size steps down at the pump. The Walbro pump also requires a 20 amp circuit, so I'm running it on 12 gauge electrical wire and just using a simple 30a toggle switch in lieu of a relay setup. A relay is the proper way to wire up the pump, however, since this is a limited use fuel system for the track, I decided to keep it simple and easy to trouble shoot with a single toggle switch.
Here's a closeup of the stock filter housing. The stock filter-housing threaded connections are metric 12x1.5. M12xJIC8 adapters for 1/2" line are about $10 a piece so if you want to save a few dollars, you can redrill and tap the fittings to a larger pipe thread like 1/4" or 3/8". The NPT to JIC adapters are about $3 a piece and they flow more. I decided to use the metric adapters because i don't own a pipe thread tap and didn't want to spend $15-$20 on taps.
I'll have the system up and running later this week, just in time for the NHRDA Desert Diesel Nationals race this weekend on March 10th. Hopefully this system solves my top-end lift pump fuel pressure issues.
The fitting is a metric 18x1.5 to JIC 8 adapter, then a standard JIC 8 90* pushlock fitting.
This is a side view to show how far forward the fitting protrudes into the fan area, as you can see, there is plenty of room.
I also added another fuel pick-up tube at the stock plastic fuel tank. The front pick-up is for my added Holley Black 140 GPH knock-off pump that feeds the stock mechanical lift pump. The newly added rear pick-up tube is for the new standalone fuel system that will utilize a single Walbro GSL-392 pump, capable of around 50 GPH at my target PSI range of 65-85 psi. The advantage of the Walbro is it's capable of almost 120 psi by itself so no need to run staged pumps, just single pump and filter setup. Also, the Walbro 392 255LPH High pressure pump is relatively inexpensive at around $100. The Walbro pumps are not designed to run on diesel fuel, however, they do still last a few years and I'm only running it at the track since the stock lift pump makes plenty of power for street use.
Here is the whole system laid out on the work bench. It'll run with 1/2" line to my 1/2-3/8" reducer, then a short run of 3/8" into the Walbro pump itself. Then 3/8" outlet from the pump all the way to used stock fuel canister I picked up for about $15-20. Then 1/2" from the stock filter to a 1/2" check valve and then 1/2" on into the front feed port on the pump. I used the mismatched line sizes because I had several 1/2" parts laying around in my spare parts bin. The 3/8" is required at the Walbro pump so that's why the line size steps down at the pump. The Walbro pump also requires a 20 amp circuit, so I'm running it on 12 gauge electrical wire and just using a simple 30a toggle switch in lieu of a relay setup. A relay is the proper way to wire up the pump, however, since this is a limited use fuel system for the track, I decided to keep it simple and easy to trouble shoot with a single toggle switch.
Here's a closeup of the stock filter housing. The stock filter-housing threaded connections are metric 12x1.5. M12xJIC8 adapters for 1/2" line are about $10 a piece so if you want to save a few dollars, you can redrill and tap the fittings to a larger pipe thread like 1/4" or 3/8". The NPT to JIC adapters are about $3 a piece and they flow more. I decided to use the metric adapters because i don't own a pipe thread tap and didn't want to spend $15-$20 on taps.
I'll have the system up and running later this week, just in time for the NHRDA Desert Diesel Nationals race this weekend on March 10th. Hopefully this system solves my top-end lift pump fuel pressure issues.
Gasoline Sucks
slow 12v
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OH boy, cant wait to see this thing turned on from 1/2 track on 
I got a fix for your traction issues at the shop, ill post a pic later
I got a fix for your traction issues at the shop, ill post a pic later
JQmile
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Pretty good guess....Joe's Dmax C10 went 11.34 at 122mph with a 1.76 60ft.
Krazeeun
Hardway Performance
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Like mine... she's a big girl too at 7000lbs race weight, 1.55 on 28" drag radials, 1.61 on my 22's & Nitto 420's. Overloads and spacers removed out back, cal-tracs & rancho adjustable 9000's on all 4 corners. I ET'd 11.49 but only ran 114.XXmph, on calculator's & whatnot those numbers don't add up but I think the low ET is purely because of how hard I come out of the hole.
Big Blue24
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The stock lift pump has a one-way diaphragm on the outlet so fuel cannot back-feed through it. However, you are correct that the factory lift pump will now have pressure working against it on the top diaphragm that it would have to overpower to be able to feed the injection pump so it's efficiency will diminish even more. After about 2 passes down the track, I'll know for sure how well the new fuel system additions are working with the old components.
Next track day will be Saturday March 10th, at the NHRDA Desert Diesel Nationals event. I'll have to use my qualifying runs to test and tune the new lift pump setup and hopefully get at least one good 11.9x pass so I'm not the slowest qualifier for the 11.90 index class.
Big Blue24
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Yeah, good 60' times will net low ET's compared to the 1/4mile trap speed. If my truck cut a 1.55 60' and still ran 95.6 MPH in the 1/8th, it would end up running 11.15 @ 119 MPH or so.
LOL
YOUNG GUNS15
Im AWESOME!!!!
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What psi do you leave the line krazeeun?
Sent from my iPhone during class
Sent from my iPhone during class
Big Blue24
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I got the fuel system buttoned up late last night. The Walbro runs nice and quiet, pushes about 110 psi with the motor off. I didn't have the opportunity to do a test run to see if it maintains good pressure in the upper rpm range.
Here's a few pictures:
The brass tee is actually a check valve with a needle valve tapped into the top access port for measuring fuel pressure. The check valve allows me to run just the mechanical system, mechanical system plus Holley Black pusher pump, or all three pumps.
The 3/8 pushlock is the pressure feed from the Walbro to the fuel filter inlet, the 1/2" pushlock is the filtered fuel outlet. I also had to fabricate a little bracket to hold the filter assembly. The filter is a Napa Gold 3395, it has the same M20x1.5 thread size and the filter canister itself has a 240 psi burst pressure rating. Best of all, it doesn't need the water drain fitting on the bottom and it only cost $11. Another filter option is the Wix 33391. It comes with a built-in twist fitting on the bottom to drain water and it is a fuel/water separator. I didn't go with the WIX because it cost $17 at my local Napa.
I will follow up with fuel pressure readings and results after the NHRDA event this Saturday. Hopefully I can get this truck dialed in to run the 11.90 index. My goal is to have it leave with a soft consistent 2.0 60' time and run 125 MPH out the back door running right at 11.90-11.95. I don't know if it has enough power to run 125 MPH trap speed, but if it does, Look out all 11.90 class fender racers, it's difficult to fender race a truck crossing the traps at 120+ MPH!!!
Here's a few pictures:
The brass tee is actually a check valve with a needle valve tapped into the top access port for measuring fuel pressure. The check valve allows me to run just the mechanical system, mechanical system plus Holley Black pusher pump, or all three pumps.
The 3/8 pushlock is the pressure feed from the Walbro to the fuel filter inlet, the 1/2" pushlock is the filtered fuel outlet. I also had to fabricate a little bracket to hold the filter assembly. The filter is a Napa Gold 3395, it has the same M20x1.5 thread size and the filter canister itself has a 240 psi burst pressure rating. Best of all, it doesn't need the water drain fitting on the bottom and it only cost $11. Another filter option is the Wix 33391. It comes with a built-in twist fitting on the bottom to drain water and it is a fuel/water separator. I didn't go with the WIX because it cost $17 at my local Napa.
I will follow up with fuel pressure readings and results after the NHRDA event this Saturday. Hopefully I can get this truck dialed in to run the 11.90 index. My goal is to have it leave with a soft consistent 2.0 60' time and run 125 MPH out the back door running right at 11.90-11.95. I don't know if it has enough power to run 125 MPH trap speed, but if it does, Look out all 11.90 class fender racers, it's difficult to fender race a truck crossing the traps at 120+ MPH!!!