95' Junker Drag Truck

how many turns did you put on your pressure adjustment? Im about to put mine back in with 5 turns, may drop back to 4 if 5 makes 250!
 
So will is running this weekend? I can't wait to see this. Make sure to get video!!!!

PS: Phil, I'm still having trouble finding a v10 converter lol. You'd think they were made of gold.
 
Cant wait to see this thing in the 11s already!!! Good luck!
 
YOUNG GUNS15 said:
how many turns did you put on your pressure adjustment? Im about to put mine back in with 5 turns, may drop back to 4 if 5 makes 250!
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When I pulled the tranny apart a few months back I checked the pressure screw and it was adjusted all the way to the end of the adjustment (9 turns). It was making 165psi in lower gears and 185psi in overdrive.

This time around I shimmed the springs with two washers and also shimmed the allen head pressure screw base with a third washer. I went 7 turns and it was almost to the point of bottoming out the springs to where they were coil bound. I suspect this is why I was seeing 250+ psi. By going down 2 turns for a grand total of 5, it dropped back to 165 psi. The pressure screw and springs are still shimmed so this is roughly equivalent to 9 turns.

Spence, on your tranny, I think I would try 7 turns, especially since your 47re valvebody is slightly different than a 47rh valvebody and it might make a little more pressure. I don't think you'll see 200 psi with just 7 turns but it might be up around 190 which is plenty for your current horse power level.
 
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Big Blue24 said:
When I pulled the tranny apart a few months back I checked the pressure screw and it was adjusted all the way to the end of the adjustment (9 turns). It was making 165psi in lower gears and 185psi in overdrive.

This time around I shimmed the springs with two washers and also shimmed the allen head pressure screw base with a third washer. I went 7 turns and it was almost to the point of bottoming out the springs to where they were coil bound. I suspect this is why I was seeing 250+ psi. By going down 2 turns for a grand total of 5, it dropped back to 165 psi. The pressure screw and springs are still shimmed so this is roughly equivalent to 9 turns.

Spence, on your tranny, I think I would try 7 turns, especially since your 47re valvebody is slightly different than a 47rh valvebody and it might make a little more pressure. I don't think you'll see 200 psi with just 7 turns but it might be up around 190 which is plenty for your current horse power level.
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Thanks! Maybe we will get this thing to work eh? :Cheer:

Side note.... does line pressure effect lockup?
 
YOUNG GUNS15 said:
Thanks! Maybe we will get this thing to work eh? :Cheer:

Side note.... does line pressure effect lockup?
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I believe line pressure does affect how "hard" the converter will lockup. Someone please correct me if I'm wrong.
 
Did phil balance the flex plate after he cut it down? think ill be taking my extra to the machine shop to have it trimmed down. Did the added flex plate screw up your clearances at all or did you kust flop everything in and it works?
 
Update: Unfortunately, no new ET records. The track was really slippery and I had a wild ride even in overdrive as the rear end skated around. My best 60' of the night was a lousy 2.015 and I need to work on tuning the wastegate on the top turbo a little more. I'm dumping drive pressure too soon causing slow spoolup. At the race in Wittman AZ at lower altitude, these twins spooled awesome, here in Las Vegas they still spool fine but not are quickly as they did in AZ. I hope someone got a few videos of my ice skating runs because I'm sure it was good for chuckle.

The new DPC converter did, however, show an increase in MPH and my new best MPH is 115.26 for a calculated average rear wheel horsepower of 561.

On my best pass of the night: 12.50, I blew a boot off right about 1200'. It was the boot that connects the two halves of my coldpipe and it had just one clamp on each side with no rolled bead or welded bead on the ends. I reinstalled the boot and attempted another pass, on that one it blew right at the 1000' mark. Finally I installed an additional clamp in the middle of the connection right over the top of where the two pipes meet and no more problems. I need to weld a bead around both of these pipes to help with reliability in the future.


Here's a picture of the two best time slips. On my blown boot pass, I was racing a guy with a 2010 Camaro SS RS 6 speed. It wasn't a very close race but still fun none-the-less.

Timeslip6-3-2011002.jpg
 
dang man I was really hoping for that thing to break into the 11s! Congrats on the new mph! That tripple disk is definately helping out!

My next track date will be the 10th. Let's see if I can beat you in our race for 11s! Haha

sent from your moms phone!
 
SCHOOL BUS said:
Get some real slicks!
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Yes, it truly needs more tire! They actually hassled me about running the roadrace slicks on street legal night. I told them it would be dangerous to run 245/75/16 michelin tires with 1200 ft lbs of torque.

dvst8r said:
Needs more fuel, rack them barrels.
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I'm getting closer to that step, just need to make a few small updates to the lift pump system since I don't think it's keeping up at the top end of the track.

YOUNG GUNS15 said:
I forgot all about that. Back to back tests would be cool to see the real world power put down at the track.

Rackem up!
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I plan to do some back to back testing. I'm curious how much power can be made by just racking the barrels on a small 160 pump.


For now, the next planned upgrade is 5.5k Darren Morrison Governor Springs to make sure I'm maintaining full rack in the pump at 4000 rpm. I know the cam in this pump won't keep up much past 3800 rpm, but at least I can keep the governor from taking away fuel.

I also need to tune these twins. I'm pretty sure I'm dumping the wastegate on the top turbo too soon. After I rig up an inter stage boost gauge and a drive pressure gauge, I'll have a much better idea what's going on.
 
well done! That guy in the new camaro probably went back to the dealer thinking there was somthing wrong with it :D
 
Gasoline Sucks said:
well done! That guy in the new camaro probably went back to the dealer thinking there was somthing wrong with it :D
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He was actually pretty cool about it and gave me a thumbs up on the return road.

When I destroy a corvette at the strip, those owners get a little upset!!!! In fact, every weekend that I run and beat up on the local Camaro's and Corvettes, the local performance shops get a boost in business..... little do they know I've got more tuning and fuel to add to the mix LOL , Maybe I can get a local shop to sponsor me on the street legal nights to ensure a steady flow of upset Vette drivers come in Saturday morning after being demoralized at the Friday night street legal races.
 
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Big Blue24 said:
I also need to tune these twins. I'm pretty sure I'm dumping the wastegate on the top turbo too soon. After I rig up an inter stage boost gauge and a drive pressure gauge, I'll have a much better idea what's going on.
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I wasn't running drive pressure to the top side of my E.D. gate when I got my twins together, it'd spool great right up to 15psi then lag it's way up to about 40psi. When I put the drive pressure to it, it spools way faster now and builds 55psi. I need to get my inter-stage boost gauge hooked up too, I think it's capable of more.
 
I'm making plenty of boost on the topend, 75 psi, my setup is just a little soft in the mid range from about 25 to 40 psi, essentially the turbo lag from when the top turbo's gate opens until the bottom turbo HT4B gets spooled up.

At the NHRDA race I attended in Whittmann, AZ which was a little lower in altitude, my truck spooled up quicker and it had almost zero hesitation in the 25-40 psi range.

The weather is hotter now, the altitude in Vegas is higher, in fact, the density altitude the other day at the track was hovering around 4000'.

The track is open again tomorrow but I won't be able to attend since my valvebody is half torn apart on the work bench right now.

Friday June 17th is looking like the next potential drag race outing. Hopefully by then I'll have the twins tuned a little better.
 
...a Corvette isnt a 1/4 mile race vehicle. Id like to see you run a 1 mile drag with one...or try turning with one like they are meant to (road course) :). Not try to be a dick, just thinking out loud.

I dunno...bragging about beating up on cars that werent designed to drag race at all kinda annoys me, even if they are crazy fast. Like a trophy truck driver beating a Prius in an off-road race and bragging about it.
 
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