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Boost ???

874 Views 14 Replies 5 Participants Last post by  pgdsm
Ok so I just go the BD 100 hp VP44 pump installed along with a juice/att, supposed to be a fass 150 but they held back the truck two days and still couldnt get it in. So I am running a new carter for. Fuel is 15psi at idle and I can drop it to 7psi.
My boost would only hit 20psi. So I took it back to the shop and we did a leak down test. Found holes in each of my lower intercooler boots. Replaced those with some spare that he had did the test again and all was well.

Now max boost is 25psi. ??? My truck already had a boost elbow on it when I bought it. So he did no install the one that came with the edge. The ones that come with the edge are they just brass with a hole drilled in them (not an adjustable screw)? Cause that is what he said they come with but it is letting air out at 20 psi so that makes me think that it is stock.

so fuel pressure is borderline no black smoke and egts are fine just lack of boost (25psi max) what could the problem be?
Is it the boost elbow?
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well it will smoke when its lugged (not black plumes like in your sig) but still black smoke. once it lights its clean. What do you mean is the elbow cranked in all the way? There is no adjustable screw just a small hole maybe less than 1/16 (I didnt see what came in the box I had a shop instal it) I just got the truck back and took it back to them when I noticed it only hit 20psi we fixed two leaks and pressurized it and everything was holding good except the brass fitting starts to leak at 20psi. After fixing the leaks I can hit 25psi of boost.
I shouldn't have fuel problems with a brand new BD vp44.
I will try pinching of the hose tommorrow and see what I can hit for boost
oh there is a huge difference from level 1 to level 5 actually there is a definite difference from level 3 to level 5. I did not check to see how much boost I was building on the stock setting (o) or even level 1. I will try that tomorrow as well.
With the definite difference I would think that the pump is tapped but it doesn't feel as strong as I thought 400hp ish should feel (dont know how much it is making but BHAF BD vp44 and juice) I thought the lack of power was because of the lack of boost (I know boost does not equal power but its still within the map at 30 psi)
Perhaps the pump is not tapped completly and I am hitting that much boost because of the BD vp44.

From level 3 to level 5 is there more going on that just added fuel, enough to make me feel a difference in power without the pump being tapped properly?
level 3 and level 5 are at subsetting 5 the others I didnt check.
The truck is alot faster than before, just not what I expected.
ok so I pinch the wastegate.
On level 0 I can hit 21psi max.
Level 1 24 PSI max
Level 5 31 psi then my alert goes off.
However that 31 psi is at like 2500 rpm.
On level 0 there is no smoke maybe and I mean maybe a light haze.
The higher the level the more smoke but its not bad. (would like more) my wife wouldnt even complain about the bit of smoke it puffs before it lights.

Now I would think with the tube clamped I would get more boost (31psi)
it is actually hard to get full boost in anything less than fourth gear. (will hit 26psi and I have to shift)

So I guess I need another boost elbow.

Now on a side note on level 0 the truck does not feel any stronger than what it did before I put in the bd vp44. (shouldn't I be able to feel 100hp?)
There is a huge difference from level 0 to 1 Boosts alot sooner and feels much stronger. Then there are small powergains going up each level from there. Does this sound about right?

Also the truck is much quieter both at idle and while driving. (less marbles in a tank sound)
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ya no way I can make 37psi so I may have a boost leak? When we tested it yesterday for a boost leak we found 2 (each of the lower intercooler boots) replaced those and it held fine but only turned it up to 25psi. So I may have a small leak that only starts to leak about 25psi. I guess I will have to build my own thing to pressurize the system. Then track down my problem. But I would still think that it is the elbow as well. as I can't hit 30psi with the juice on 5 with out the tube being clamped.
the shop that I had everything installed at had a home built deal. I am just going to build one. IF you search someone has posted how to build one or what part numbers to get at napa.

Basically you want a regulator and some tubing to go over your turbo so you can hook your air line up to a adjust the psi that you are putting into the system then start listening for leaks. Or use soapy water. (i just listened and that may not have been enough so use soap)
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