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Ryan
11-14-2002, 01:39 PM
I just got my boost guage hooked up last night. At Idle the guage shows no boost, cruising at 55mph, about 1700rpm, it shows about 6psi, standing on it in 3rd gear it will reach almost 19psi. Are these numbers normal? I was expecting to see a little bit of boost at idle.<br><br>Ryan

11-14-2002, 01:52 PM
The numbers sound about right. I believe max boost is about 21 psi on the stock, unbombed '02/HX35. Try stomping on it in fourth -- you'll have time to max the boost. No boost at idle. Cruising at 65, I run 6-8 psi at level. <br><br>GP

jweir
11-14-2002, 01:56 PM
Ryan,<br><br>Those numbers sound about right. That is what I had on my truck when it was stock, the waste gate is set at about 19. With the comp and boost elbow, I can hit about 34 PSI at WOT with the comp set at 5X5. Cruising empty down the higway at 60 or so, there is very little boost, the mighty CTD is not working at all. Add a trailer with some weight and the boost will rise because we are making the engine work more.<br><br>Hope this answers your questions!<br><br>Jim

KatDiesel
11-14-2002, 01:59 PM
You won't see any boost at idle unless you slap on a supercharger to feed the turbo. You won't see the boost gauge move even if you put it in neutral and rev it up, although there are some very fast spooling performance turbos that will spool in neutral. 19 to 20 psi is the factory wastegate setting so your fine. The cruise sounds alright too, it will change with wind resistence as well.....at 70mph I am usually at 8 to 10psi.

Ryan
11-14-2002, 02:23 PM
Thanks all. I was a lot less worried when it approached the 19psi in 3rd, than I was when i started the truck and the guage didn't move.

BigBlue
11-14-2002, 05:44 PM
If you push boost at idle then I don't ever want to meet you on the road. That's power. Mine used to hit 19. Now I can hit 30 without trying and have any touched 40 for a split sec. Most I have ever pushed for a long time is 37. Comp was in EZ mode. I usually hit about 30. All of this on a stock HY35 9cm2 wastegate. Had the turbo inspected and it is fine.

KatDiesel
11-14-2002, 05:47 PM
<br>If you push boost at idle then I don't ever want to meet you on the road. That's power. Mine used to hit 19. Now I can hit 30 without trying and have any touched 40 for a split sec. Most I have ever pushed for a long time is 37. Comp was in EZ mode. I usually hit about 30. All of this on a stock HY35 9cm2 wastegate. Had the turbo inspected and it is fine.<br><br><br>You could have 200hp or 500hp ...wether you have boost at idle is either one **** fast spooling turbo, or you have a supercharger installed on top of the turbo. I have &quot;heard&quot; of one such truck that has 11 psi at idle feeding an H2E.

98rammer
11-14-2002, 06:51 PM
<br>You could have 200hp or 500hp ...wether you have boost at idle is either one **** fast spooling turbo, or you have a supercharger installed on top of the turbo. I have &quot;heard&quot; of one such truck that has 11 psi at idle feeding an H2E.<br><br><br>i'd love to see that truck!<br><br>BB-talk about overspooling on an hy :o<br><br>Tom