The turbos are pretty much the same thing except with a different mount on the back for the up pipes. The e99 charger is closer in similarities to the OBS than it is to the l99-03.

 

Pretty much the same thing? Not sure how you figure that...

It has a smaller, wastegated exhaust housing and uses a smaller turbine shaft (same one that is used on 99+) so it spools up faster and regulates boost pressure.

The only real difference between it and the 99+ turbo, is the size of the compressor cover. It's the same cartridge (CHRA).

 

Turbine and compressor wheels are the same. They just throw a different sized AR exhaust housing on it. Such little difference in obs to 03.

Now something that's significantly different stock vs KC38R. Larger turbine, larger comp wheel.

I guess compared to the chargers I mess with. The details between obs and l99 are semantics.

 

What kind of gains were you hoping for with the swap? Do you have stock injectors?

About the only thing you will notice is a tad quicker spool up.

No real need to regulate boost pressure if you are running stock sticks. Not enough fuel to harm the turbo.

 

Yes, everything else is stock. Pulled all the injectors and flow tested/resealed them while it was down.

I wasn't looking for any huge gains, I just know from working on these trucks and rebuilding turbos that the original one (like pretty much all non-wastegated turbos) is very weak. Plus I already had the other turbo and up-pipe adapter, just needed some minor mods to make it work.

Also, it's much more than a "tad quicker" to spool up now I might add! The wastegate is there because the turbo is capable of more boost and can be regulated to consistent boost pressures, whereas the non-wastegated turbo is simply designed where it cannot overboost.

 

turbine wheel is the same size for the e99 and obs 7.3's. the only similarity between the e99 and l99 turbos is the small exhaust housing and collector mount.

I would tighten the wastegate down all the way as well. since obs injectors are 90cc instead of 120-140cc you wont need to worry about exhaust back pressure getting super high.

and without a wastegate solenoid you don't need a line attaching the the nipple on the wastegate either

 

Compressor wheel's are the same size for all years, OBS just used a larger diameter turbine shaft.

I disagree with you slightly on the wastegate... I tightened it quite a bit, but as you can see from the pictures it's tee'd right off the MAP hose. What's the point of a wastegate if you don't hook it up? Also, that's actually a wastegate pot from a Navistar 444E turbo, since there were no wastegate hoses before it was just easier to hook up because it uses the same ¼" hose that the MAP sensor uses. I'm considering using one for a little higher pressure, perhaps a Holset, after I get the scanner and see what kind of boost it's making right now.

 

No need for an aftermarket wastegate, complete waste of money. When tightened down and with the red line unplugged (99-03 trucks) it will hold 25+ psi of boost.

the reason most of us unplug the red line to wastegate is because the pcm will command the wastegate solenoid, not the map, to open the wastegate at 5-7 psi.

The wastegate will still open from backpressure but not from the pcm commanding it to open it via the wastegate solenoid.

OBS trucks don't have a wastegate solenoid or the pcm function to open the wastegate.

So having it hooked up to your map line effectively opens it all the time releasing boost pressure/power. Which will kill top end power

 

So having it [wastegate] hooked up to your map line effectively opens it all the time releasing boost pressure/power. Which will kill top end power

I'm not sure about that... I would argue that it relieves some exhaust back pressure while maintaining consistent boost pressure.

I'm well aware there are bigger, badder turbos out there, but I'm not trying to build a hot rod. I already had this turbo, just picked up a few small pieces to complete the swap because the original turbos are pitiful. Would I pay $1000 for this upgrade? Hell no! But it only cost me about $200 in parts, looks factory and works awesome!

I submit this graphic showing irrefutably that this wastegated turbo is "better"

 

Have you hooked the wastegate to a boost gauge to verify? I have done it. It would open at 7 psi like clockwork on my truck.

I would unhook it from the map line. The pressure from the map line will open it too early.

The wastegate will still open from back pressure with it unhooked.

 

Have you hooked the wastegate to a boost gauge to verify?

No manual gauge yet, its on the list though. Wastegate opens at about 25psi.

Correction: After installing a manual boost gauge, the wastegate was limiting boost to ~15psi, even with a pretty heavy preload on the actuator. Replaced it with one from an HE351CW and now its up to 20psi. I may try and tweak this one a little more but plan to replace it with one from an HX series.

 

That is exactly correct, if you hook up the wastegate on a 99+ directly it will start to open at 7psi. The reason is because the wastegate is connector through the WGC solenoid so the PCM can control boost pressure and limit it down as low as 7psi. The WGC valve can divert manifold pressure to the wastegate or back to the intake to maintain whatever boost the PCM wants based on its PWM input.

This truck doesn't have a WGC and its not the same actuator.

 

International made the engine. The wastegates are all the same.

The map sensor sees whatever boost is applied to it.

So on a hard run you open the wastegate almost immediately.

Go in the 99-03 section and read the red tube mod thread for better understanding

 

International made the engine. The wastegates are all the same.

I don't think you are understanding. I mean like a Navistar 444E Engine from an International truck, not a pickup. Clearly it is not the same actuator, if you look at the pictures, mine has a 1/4" port on the side of the pot where all the pickups use an 1/8" port on top.

Go in the 99-03 section and read the red tube mod thread for better understanding

Better understanding? I just explained to you how it worked and it doesn't apply to this truck anyway.

 

I will try my best to help out and clear a few things up.

Wastegates simply bleed off excess exhaust pressure. This can and will limit boost. A wastegate is used to keep exhaust back pressure in check, limit boost, and keep from over speeding a turbo. A Wastegate WILL NOT increase spool up... it does not have that capability. It has the ability only to do the exact opposite, which is to release pressure.

There is some slight confusion because a wastegate can be used in conjunction with a SMALLER a/r housing. Thus spooling up faster. But the wastegate does not affect the spool up... IT IS THE SMALLER A/R HOUSING that makes the turbo spool faster. The smaller a/r housing is more restrictive and increases drive pressure faster which will spool the turbo faster, but can choke out on the top end. That is why you put a wastegate on the smaller turbine housing so it can bleed off the excess pressure. This does not really come into affect unless you are running larger injectors. The stock injectors wont push the turbo hard enough to have any major issues.

A larger turbine housing does not require a wastegate because it will not choke out as easy.

 

See that's what I have always understood with turbochargers for the 7.3's. If you wanted a hellacious spool up you take the .84 housing turbo from superduty's and then boom there you go, except for that backpressure issue that comes with it, therefor the need for the wastegate. You may have a heck of a spool up compared to the 1.15 housing but the backpressure is way higher than what stock was for an obs, even with the puny 90cc injectors.