Hoss

Despite what my signature says, I have not yet installed the boost elbow that came with my EZ (just like I haven't yet installed the DPPI exhaust that the nice UPS man dropped off today).

So, what exactly does this little boost elbow do? Doesn't look like much.

reb0957

It has a small orifice in it and a bleed hole. It causes the waste gate to read boost pressure slower than normal. On a 0 to 70 run with EZ on level 4 I was at 1350 degrees. Now I am well over 85 and less than 1200 degrees. It raised my boost psi from 23 max to 36 max.

Hoss

Okay....so talk to me like I'm a diesel dummy...

What exactly does it do when you raise the boost? Besides lower EGT's (obviously from the post above), what are the benefits or the negative things about raising the boost? What is the maximum boost our 3rd Gens should have?

phox_mulder

As you add fuel, you need more air to burn it completely,
otherwise it's wasted and goes out the tailpipe as smoke or soot.

The stock turbo can go up to around 30-35psi before it is out of its range.
The wasegate comes from the factory set at around 20psi.

Just raising boost won't accomplish anything unless you have the fuel to burn.

After 30-35psi, the stock turbo is actually heating the air, negating any EGT reduction,
and is in danger of overspinning and grenading itself, spewing metal chunks into the engine.


phox

Hoss

So....if the Edge EZ says that it works equally well with or without the boost elbow....one could take that to mean that it is not causing more fuel to be pumped than 20 psi of boost would be able to burn....meaning the boost elbow isn't really necessary.....but it COULD help keep your EGT's lower. Is that correct?

What type of mods would make the boost go above the 30-35 psi that the stock turbo is designed for? I trust that the EZ won't do that since Edge says that the EZ is designed within the parameters of the truck. Right??

wannadiesel

The boost elbow will keep your EGT's down, but it won't make more power. It's not absolutely necessary unless want to use the added power that the EZ gives you in a towing situation. Without the elbow you will need to watch the pyro very carefully when towing. I can't imagine why you wouldn't want to put the boost elbow on the truck.

The boost elbow will not allow the turbo to make unsafe levels of boost even if you add more mods like injectors or a bigger fueling box. It just puts a small leak in the boost line to the wastegate actuator, which keeps the wastegate from working until around 35 psi. The wastegate still works to control boost, the boost elbow just raises the limit.

Hoss

I see. That makes perfect sense.

However, that raises another question. The DiPricol boost gauge that DPPI sells says that it comes with a T that fits in the rubber boost line from the turbo. If you're using this boost elbow with this T they have, wouldn't that give you a lower boost reading than what you're actually making?? Go HERE to see what I'm talking about.

If I've been informed correctly, Geno's sends the same gauge with a bolt of some sort instead of the T referenced above. I'm thinking that would be the better route to go if you're using the boost elbow. Correct??

wannadiesel

I agree with you that teeing into the boost line would cause a low reading with the boost elbow installed. You probably wouldn't see over 25 psi set up that way. I don't know whether Geno's sends the boost bolt but that is the way to go IMO. You always want to take your boost reading after the intercooler, that's what the engine sees.

GreenZ

Hoss,
I bought my Di Pricol gauges from Geno's. Geno's sent the fittings required to tap the horn. I did not want to tap the horn so I bought the manifold bolt from Rip Rook (Source Automotive) - works great and looks cleaner IMO.

Regarding the "T", I know Powerstrokes use the T but I have not seen that set-up used on a Cummins?

reb0957

Hoss,
Geno's will give you the boost bolt for free so you dont have to tap the horn. Just ask for it when you buy your gauges.

TON4FUN

I just bought a Edge EZ off e-bay used and they guy says the unit does not come with the boost elbow. Can someone tell me how to make or get one?