95' Junker Drag Truck

CorneliusRox said:
Wow, nice. So do you only turn on the Walbro when you're going down the track? And there are no issues with going through the stock mechanical pump like it being a limit when you get into it?

And where do you have the filters then?

95 psi at full load sounds fun ha ha, is there more of a risk of making the rack stick at that point?
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Stock filter in stock location for the stock mechanical pump/pusher Holley Black setup.

Separate stock filter head & filter mounted to the firewall for the stand-alone Walbro pump. For best ET's, I turn the Walbro on as I'm bumping into the staging beams.

For street use, the Walbro never comes on and the Holley Black (knock off) only comes on when I need that extra 80 HP it provides.

I would imagine the extra fuel pressure has no negative effect on whether or not the rack sticks. If anything, keeping the plunger full of fuel would be a safety feature to ensure the rack doesn't stick.
 
Do you lock at the top of 2nd?

And did I read that right? 80hp if you go from 8Xpsi to 95psi fuel pressure? I've heard 160 pumps like pressure, but damn! I wonder if 180 pumps would net anything close to that?
 
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Good my ats converter just got bavk from phil at dpc he loosened it up for me and had itback to me in 3 days exactly as promised. great guy.

madmike- im stealing wills idea and running a 392 from a sump to the front of the pump but im putting it on a hobs pressureswitch with a relay so it only comes on over 25psi boost. I have every thing I need to get the system together I just need to run the tank low and install a sump. if a 180 makes 40 more hp it was worth the $150
 
madmikeismad said:
Do you lock at the top of 2nd?

And did I read that right? 80hp if you go from 8Xpsi to 95psi fuel pressure? I've heard 160 pumps like pressure, but damn! I wonder if 180 pumps would net anything close to that?
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80hp from stock mechanical to stock + knock off holly.
 
Lostnwalmart said:
80hp from stock mechanical to stock + knock off holly.
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The way I read it, he's running an electric pump into the mechanical, plus an extra electric pump to the front port. so 2 electric and the stock mechanical.

But either way, I'm more curious about the psi #'s. 80 is already high, but 80hp gain when going to 95psi is awesome.
 
madmikeismad said:
The way I read it, he's running an electric pump into the mechanical, plus an extra electric pump to the front port. so 2 electric and the stock mechanical.

But either way, I'm more curious about the psi #'s. 80 is already high, but 80hp gain when going to 95psi is awesome.
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It's not the 80psi-95psi, it's stock fuel pressure to 95psi he is saying he gains 80hp from
 
Big Blue24 said:
Stock filter in stock location for the stock mechanical pump/pusher Holley Black setup.

Separate stock filter head & filter mounted to the firewall for the stand-alone Walbro pump. For best ET's, I turn the Walbro on as I'm bumping into the staging beams.

For street use, the Walbro never comes on and the Holley Black (knock off) only comes on when I need that extra 80 HP it provides.

I would imagine the extra fuel pressure has no negative effect on whether or not the rack sticks. If anything, keeping the plunger full of fuel would be a safety feature to ensure the rack doesn't stick.
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That makes sense to me about extra pressure will keep the rack lubricated, but I have heard it both ways.
If you are getting an extra 80hp off the Holley knock off, what is the different in fuel pressure at WOT?
 
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madmikeismad said:
Do you lock at the top of 2nd?

And did I read that right? 80hp if you go from 8Xpsi to 95psi fuel pressure? I've heard 160 pumps like pressure, but damn! I wonder if 180 pumps would net anything close to that?
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I turn on the lock-up switch while staging, it locks up on the 1-2 gear shift.

Lostnwalmart said:
80hp from stock mechanical to stock + knock off holly.
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Correct!

madmikeismad said:
The way I read it, he's running an electric pump into the mechanical, plus an extra electric pump to the front port. so 2 electric and the stock mechanical.

But either way, I'm more curious about the psi #'s. 80 is already high, but 80hp gain when going to 95psi is awesome.
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Correct, two electrical lift pumps. At the NHRDA race last weekend, the Walbro was worth an additional 1 MPH in the 1/8th so roughly 2 MPH in the 1/4. This calculates to roughly 35 average horsepower going from 80 psi which falls to roughly 65psi WOT, to 110 psi which falls to roughly 95psi WOT.

So to clarify, the Holley Black Knockoff pusher pump added 80 average HP, recent track numbers show that the Walbro front port feed at 95 psi adds an additional 35 average HP.

Another interesting note, the new cam raised the stock mechanical fuel pump pressure from 50 psi to 60 psi. I spoke with Zach and he said the pump lobe is the stock profile, so my factory cam lobe might have been worn as there's no other explanation for the extra 10 psi from the stock pump.
 
will, merlon here from havasu. I am building a 95 drag truck and found that a dana 70 from an 89 dodge diesel will fit nice under the truck, it has 35 spline axles and is 5.5 inches narower than 95 disc brake coversions are very easy on them for your faster speeds. The older dodge B vans are even narower than 89 trucks they are only dana 60 though thought you might like the info for you qwest of a bigger tire good job at the track.
 
Last night I bumped the timing up to 30*, it was and has been set to 26* ever since I advanced it from the stock 12.4* years ago.

On the street, it is difficult to judge seat of the pants power gains since it will easily spin street tires.


So, I loaded it up with 200 lbs of tires and wheels in the rear end, loaded up a buddy as a passenger, and went out on a closed course with fresh concrete pavement much like a section of new concrete paved freeway.

Rolled into it at 2500 rpm in 3rd gear (with 33" all terrains at 30 psi) or 69 MPH and it was nothing but tire smoke when the big turbo lit.

So, I tried it again at 3000 rpm in 3rd gear, or 82 MPH and it still spins!!!

Needless to say, it's making good horsepower with the timing bump. There's a drag race event next weekend at the old airport in St George, UT. I plan to try my hand at marginally prepped airstrip drag racing.... I don't expect great 60' times so it will be almost impossible to beat my current best 10.90 ET, however, I might be able to improve upon my trap speed if I don't have to repeatedly lift once off the line.
 
Sounds like you need a heavier passenger, I know a guy that can help. On a more serious note have you checked the ladder/track to see if they have moved or could be adjusted to help a little
 
I know it's frowned upon, but have you considered adding ballast in the rear? Unless you are loading the engine 100% already, the extra ballast might load it enough to counter the weight it add's, and give you that extra traction. Unless you'd have to add 1000lbs or something.

Of course it's late, I'm at work, I'm tired, and I could just be talking out of my @ss.
 
madmikeismad said:
I know it's frowned upon, but have you considered adding ballast in the rear? Unless you are loading the engine 100% already, the extra ballast might load it enough to counter the weight it add's, and give you that extra traction. Unless you'd have to add 1000lbs or something.

Of course it's late, I'm at work, I'm tired, and I could just be talking out of my @ss.
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The truck has 250 lbs of steel plates/ballast bolted in the passenger rear corner of the bed for the very reason you listed, the HP was much greater than the ET because it was so traction limited.

With slicks at the track, it has had no issues with spinning or tire slippage after the first 30-40'.

On the street, with street tires, it would probably take 1000# in the bed to keep it from spinning down at the 25-50 MPH range. Adding 1000# would definitely neuter the truck on the topend and make it feel like a slow tank.




97rada said:
Small turbo limited ?
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That's a tough question:

I don't have the wastegate tuned perfectly yet, need more track time. At the last race event, it was making 65 psi from the HT4B and just 85 psi total. It's clear that the ported internal wastegate is flowing well, the question is will it pick-up horsepower if the wastegate is tightened down a little to let the He351cw retain more exhaust energy to do more compression work? Without track testing, I won't know. One other factor is the He351cw is probably under-turbined meaning it would benefit from a larger turbine wheel. If the wastegate fine tuning doesn't create favorable results, I will likely machine the HE's exhaust housing to accept a larger turbine wheel from an HX40.
 
Is that putting the 4b outside it's working window? Are you running any kind of water injection to cool off the air some? This might lower boost a little but make it more efficient.
 
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