Boost Pressures Stock or EZ'd

[obie1]

I have a general observation/ question with hopefully someone smarter than me giving me an answer.



With the Edge EZ on my truck (see sig) my Boost goes only to the 23 - 25 and that's it. I do not have the Edge Boost elbow in as it controls mainly the EGT's (FWIK).



The EGT's are not a problem as it approaches 1300 DEGF I get out of it.



So my question is why some users have higher boost pressures 30+? I have seen from other users who have "bombed" their units is 25 range (close to stock). That is assuming the boost elbow was not replaced.



So what gives?

 

[Turbo Tim 1]

Without the boost elbow in your wastegate is opening and dumping any possibility of making more boost.

 

[bpenrod]

Mine runs at 34-36 pounds boost with the EZ boost elbow installed.

 

[KKlepfer]

From what I've gathered from other threads concerning the boost elbow that comes w/ the EZ, the increase in pressure as a result of the elbow is canceled out by the increase in intake air temps that occurs as a result. Thus users are not noticing much of a difference with or without the elbow. (except for increased boost pressures). If you do a search on this you'll get a more technical explanation than I'm able to give.

 

[DaveMorris]

obie1,

I have to disagree, my truck looses alot of low end with the elbow installed, pull it off and I am smoking tires taking off, with the elbow I have less turbo lag but still can barely spin tires from a dead stop.



I have tried it both ways and even sent the box back for a replacement with the same results. I can not comment on the EGT's yet, I am about to re-install the elbow and compare. From a dead stop to about 90 mph I will just tap 1400 pre turbo. I will dirve it for another week with the elbow and see the temps on the same runs.



BUT THERE IS A BIG DIFFERENCE WITH AND WITHOUT the elbow on the low end side of things.



Dave Morris

 

[gsbrockman]

Originally posted by bpenrod

Mine runs at 34-36 pounds boost with the EZ boost elbow installed.

Mine, too..... I estimate. My boost gauge only goes to 30 psi. Had it up to 1400* tonight around 105 mph on a short blast on the interstate between two exits.

Greg

 

[Turbo Tim 1]

Originally posted by DaveMorris

obie1,

I have to disagree, my truck looses alot of low end with the elbow installed, pull it off and I am smoking tires taking off, with the elbow I have less turbo lag but still can barely spin tires from a dead stop.



Dave Morris

Now don't take this personally but this doesn't make any sense, essentailly the elbow doesn't change anything until you get to the point of factory wastegate operation, at which point the elbow allows the wastegate to stay closed longer by bleeding off acuation pressure allowing for more boost. It takes air to burn fuel which is why they design these boxes for use with a elbow so that you're not blowing black smoke uncontrollably. The boost fooler part of the box allows you to fuel without having the ECM required boost.

 

[MMeier]

I have to agree with Turbo Tim here pretty much, mine will hit upwards of 40 PSI on cooler days with EGT's of about 1250-1350 , with the EZ on level6 . I presently set it back to level 4 for now, might try level 6 now that its warming up around here and see what happens!

 

[DaveMorris]

Turbo Tim 1,

On paper I would completely agree with you, but you better come have a LONG talk with my truck then cause I am telling you a "real life experience" not just a rumor... .



I have had the EZ (LVL-3) on the truck since it had 700 miles on it (10K now). At about 7K I decided to bump up to LVL-4, it was a fairly large improvement down low but fell off (still more power than stock) on Mid and upper range. So I decided to finally put the elbow on, as soon as I did I lost that low end punch and didn't gain anything more up top. I replaced the AirFilter and Fuel filter but it didn't help.



So thinking I had a bad box, I swapped it for a new one.



Put in the new box and got the same thing, so I drove straight home, pulled the elbow back off and got that low end back. I was going to dyno the truck with the elbow on and off, but I don't think a dyno will show where I am really loosing the power since it is from idle to about 1500 rpms.



Here are the results:

Dead stop (idle) to floor:

-Edge EZ on level 3 no elbow = tire spin in first, and tire scuffing in second.

-Edge EZ on level 4 no elbow = tire spin in first, and second.

-Edge EZ on level 4 w/ elbow = barely tire spin in first, none in second.



Now this may not be technical, but I can easily duplicate this anytime so I would consider it a pretty accurate statement.



Again, maybe it is not right on paper but I have a truck 60 feet away from me that says different in real world test. I am wondering if the TST (EZ type box) has a boost elbow because I hear that they come on alot sooner than the EZ. If they don't have a elbow, then this maybe how.



I like my Edge box and am not trying to put it down in any way, but this is my experience and that is with two different EZ boxes and I don't think that I have gotten 2 bad ones back to back. This must just be the way they perform.



Dave

 

[Jengle]

TST has it's own elbow that works at a different rate than the Edge one. Someone on here used the Edge elbow and the TST box and grenaded the turbo, because of the difference. So, use the elbow that is made for the box, whichever you use.

 

[obie1]

Great feedback.



Its cooler today down here in Texas and today I took the truck up to 100+, sure enough got 34 psi boost/1300 DEGF without the boost elbow. No black smoke (or at least nothing I can see in the rearview).



Am I understanding correctly the wastegate is mainly for "clean" burn? I tought it was to help control EGT's mainly?

 

[Turbo Tim 1]

The wastegate keeps the boost from going past a certain pressure.

 

[CLAYTON]

With my elbow it put my boost up to 40+ psi. The stock turbo on these trucks are only effective up to 35psi right? I liked it better without the elbow on. I haven't had a chance to tow with the elbow to see if that helps with temps. I am going to take it off for a bit.