Boost gauge readings Wrong?

[Cummnzpowr]

just got my boost gauge set up . . it's reading as follows:
0- at idle
6-8psi- at 75 mph on freeway
24psi-when stomped to floor
--the only thing is . . i had to connect a cut boost line with electrical tape, so maybe it's not reading the pressure correctly. . please see signature for power mods to determine if those could be correct boost pressure numbers... any help??

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Greg's 1993 D250 4x2. . 5-speed. . extended cab. . longbed. . bright white. . tinted windows. . 4-inch stack through bed. . K&N air filter. . holes in air box. . Piers' "tweak inductioned fuel pump"... . PW injectors... 12CM housing... Isspro Pyro &Boost guages. . "The{smoking}Phantom"

 

[David Phipps/Mike Hurd]

personally, seems like you should be getting more on the top end. rest sounds normal. IMHO Mike

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http://hometown. aol.com/hotshothauler/myhomepage/business.html 2000, CTD 3500, Air brakes on truck & trailer. 193,000 miles todate. DOT custom built sleeper unit. pulling a 40' G/N flatbed
2000 FL-70 Pulling a 48' low boy. 200,000 miles
Just bought another 92 D-350 215 P-Pump motor and NV 4500 180,000 miles 24 lbs boost all stock For now

 

[AlK]

Those numbers are just about bang on with my truck.

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92-LE,4x4,5spd,3. 54,Borgeson steering shaft, Tach,Isspro Pyro & Boost, 16cm2, PW injectors

 

[Wirenut]

I'm getting 37psi with a setup close to yours but I've seen others run about the same boost as you with that setup. I think you gotta add the second stack to get the other 13psi! #ad


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• '93 250 LE 4x4 5spd 4:10 Loaded,dual 5" chrome stacks,12cm² turbo(37psi),PW injectors,K&N,pyro/boost,US Gear E-Brake,tool box,CB,10" AR rims, 285/75/16 Bf goodrich. "wirenut_21529" on Yahoo Messenger
• '97 Ford B-Series school bus (5. 9 Cummins!)I'm gonna Bomb it!
• '94 GMC 2500 6. 5L Turbo

PICTURES.

 

[fastmark]

Two of you guys on this post have the 12cm housing installed. I bought a lot of parts from my supplier the other day and he said he would give me a 12cm housing. I am going with the bd brake and 3. 5 exhaust and gauges. My guestion is this, do you think that the 12cm is TOO small and I will have trouble towing when is gets to out 100 degree summmer days here in west Texas? He said to just try it and if it gets a liitle hot, just downshift to give it more air. If EGT are still to high, we can try injectors or the 16 housing. What do you think?

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Mark Faught, 92 ext cab service truck and a 84 crew cab one ton dually with a 91 cummins and NV 4500.

 

[David Phipps/Mike Hurd]

Mark, before I went with a 215 horse P-pump motor in my other truck I was running a 12cm . I did have the Banks intercooler and 3 1/2" ext and the us gear brake. I hauled 36,000 lbs every day till I sold my rig and never saw more than 1200 pre turbo. This was pulling in 120 deg weather and steep grades. Of course, you'd have to downshift to get up them steep grades but not because of egt's. At that time my pump was all stock and running 180 hp injectors. We did alot of Fla to Cali runs and it worked just fine for us. Bear in mind the nv4500 does not like to be lugged in 5th while towing you could loose 5th gear #ad
other than that load and go. Mike

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http://hometown. aol.com/hotshothauler/myhomepage/business.html 2000, CTD 3500, Air brakes on truck & trailer. 202,000 miles todate. DOT custom built sleeper unit. pulling a 40' G/N flatbed
2000 FL-70 Pulling a 48' low boy. 211,000 miles
Just bought another 92 D-350 215 P-Pump motor and NV 4500 180,000 miles 24 lbs boost all stock For now

 

[Wirenut]

I don't anything to tow (yet) but I can get mine pretty hot just going uphill unloaded. Say for instance, a powerstroke tries to pass me uphill on the interstate and I let 'er eat in 5th gear, my egt's are up to 900deg. post turbo in about 10 seconds #ad
But the 'stroke is far behind in that much time, so I don't mind the heat.

 

[BigRig]

those boost numbers are almost exactly the same as mine.

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'92,CC,4x4,ctd,3. 54's,16cm,lucas injectors,isspro boost and pyro gauges,firestone air bags,BD 3. 5 exhaust,factory tach

 

[Scot]

Ok guys, I keep reading these boost numbers and am not even close. I have a 93 5 spd. As far as I can determine it was stock when I got it (69K miles)

The pump does not ever appear to have been tampered with. I put the boost and EGT on prior to turning it up. It would run mostly 0psi @70mph, but would go to 14 WOT.

I went to 16cm hot side housing, smoke screw in +2 turns, full power ~+ 1 1/2 and star wheel 2 1/2 from the bottom, diaphragm at 3pm. New airfilter, fuel filter and set valves.

Oddly enough the star wheel was 5/8 turn off of bottom when I started. The diaphragm was already at 3pm. The smoke screw is pretty much flush with the top of nut now. The pin is making a mark (line) on the diaphragm shaft so I believe it is free. If someone tweaked it they did not leave a mark. The paint on the screws was intact.

So now I can get 3psi at 70 mph on flat ground and will go to 24psi WOT. EGT runs ~650 deg at 70 on flat ground. Will climb to 900 deg on a hill unloaded. It also will blow a huge black cloud if you get on it until the turbo spools up in lower gears.

I see no evidence of leaks to the intercooler. (how would you check anyway?) What adjustment actually builds the booost other than turning the fuel up? Any ideas?