Engine/Transmission (1998.5 - 2002) boost

[Tractorat]

I'm taking my truck in to have the boost checked sometime in the next couple of days. I really need to get off my butt and have some gauges installed.



My only mod is and Edge EZ box. What kind of boost should I be seeing with only that upgrade ?



Thanks

TRat

 

[JCyrbok]

I'm taking my truck in to have the boost checked sometime in the next couple of days. I really need to get off my butt and have some gauges installed.



My only mod is and Edge EZ box. What kind of boost should I be seeing with only that upgrade ?



Thanks

TRat

with only that mod you should see 20-22psi (which is just about stock).



At least that is what I see on my truck with an EZ, 4inch exhaust and open air filter.



J-

 

[Bob4x4]

The Edge EZ's were shipped with a modified boost fitting,if it is in place you should see low 30 psi under full load

 

[Tractorat]

Bob4X4,



That is actually what I was expecting to hear. I found the original invoice of when I had the ez installed, and it said that they measured 30lbs of boost at that time. A couple of years later, I brought it in for a check, and they said it was only about 24lbs of boost. When I questioned that, the guy told me that was all I should expect. Since this shop specializes in power upgrades for Dodge's, I figured that the original 30 lbs on my invoice was just a typo, so I shrugged my shoulders and left it at the (How would I know ?)



So, with a simi educated guess now, I think I have a boost problem that has been there for a while. The truck doesn't smoke at all, and I don't really know where to look for other boost leak symptoms. So, I guess the good news is that this will make be take it back to them just to be sure.



Thanks for your input.



TRat

 

[Road Dog]

As I understand, an '02 auto has a HY35 turbo and uses a J-hook to hold the waste gate closed instead of the boost fitting on earlier turbos.

One version of a J-hook:#ad

 

[Tractorat]

I know a j hook was installed when I first had the ez installed. Where would I find that to make sure it's still there /

 

[Tractorat]

Correction Xhook not a J hook

Correction. The invoice for my Edge EZ included an "Xhook", not a j hook

 

[Road Dog]

It's under the turbo on block side. It runs horizontally from a box/diaphram on the intake side to the wastegate on the exhaust side.

 

[Tractorat]

Thanks



TRat

 

[HBarlow]

The '01/'02 HO six speeds produced 26 lbs. of boost.

2001 ISB engine specs

 

[Tractorat]

Its an automatic, and therefore not an HO. But the link you sent does have the correct information for my truck as well.



Thanks for sending the link. I've saved it. It looks like a good resource to have.

 

[CToney]

My brother's '01 HO would make 30psi with ez add a FASS and it made 32psi. After the EZ died he put in 40hp injectors and makes 27 psi now.

 

[ArmandoCantu]

I have a '00, auto, 4x4. I installed a Hpertech program, Stage 3. K&N filter w/stock intake system, turbo and exhaust but with an ATS intake elbow and silicone hose kit. FASS 95 fuel filter system. The truck runs and pulls great - it's fun. I wanted a better than stock HP truck to tow and daily drive. Truck has 3. 54 gears w/35" tires. I have Autometer gauges and with my 8 - 10K pound race car trailer I see 1,000 to 1200 degrees EGTs and maybe 8 pounds of boost cruising. When I start off a stop I'll see 15 pounds or so until I get in high gear and cruising. Seems to me I should see more? Or I'm thinking because of the large tires and high gears this may be normal. Any ideas or comments? Especially if there is anything I can do to up the boost pressure (25# or so) without changing gears, tires or turbo? Thanks.



P. S. I installed an ATS Stage II transmission and 5-star convertor. Wow, what a difference - I'm totally impressed! Truck runs and shifts like a scalded ape!!!

 

[Bob4x4]

Max boost #'s are seen under max load/accell,cruise level boost will/should be much less

 

[Road Dog]

My boost tops out at 15psi and I haven't looked into why. The boost is limited by the wastegate and needs a mechanical solution -- either a boost elbow or J-hook (depending on the turbo) to hold the wastegate closed to a higher boost. The ecm will also defuel at some point -- around 25psi I think -- and some programmers change that limit.

 

[bromano676]

My experience is that the ECM starts to defuel around 16 pounds of boost until it reaches 21 pounds and the waste gate is fully open and the truck is defueled.



I installed a quadzilla boost fooler and the boost went to 28 pounds. I have no j hook or boost elbow. I have a mechanical boost gauge t'd off of the waste gate port.



I took the quadzilla out and installed a edge juice. I am now reading 21 pounds of boost again. I am reading it both at the mechnical gauge, which is still t'd off the waste gate, and on the monitor which reads MAPP sensor pressure.



I believe that the waste gate does some boost limiting, but not all of it. I believe that the ECM is a big contibutor to the boost.



I have the boost elbow, but I can't turn up the edge anyway, I want to replace the stock clutch first, so I have not put it in yet. I also have an airdog that i need to put in.

 

[Diesel Gunner]

Interesting. When my truck was stock my gauge only showed 19. 5lbs of boost. Added the XZT and Boost only increased to about 21 max. Even with the Boost line blocked off boost remained the same. Then, I safety wired the waste gate shut and I was able to get 28lbs of boost. I figured that the waste gate was being blown open even when the control diaphram was disconnected.



Before I took it over to pay my extra taxes at the smog station I cut the safety wire off and boost is back to 20 or so max. The only difference that I have noticed is a slight bit more smoke with the box on.



Anybody have any ideas about what is going on?