Turbo and egt issue.

I figured you guys get this question a lot about turbos on a vp44 truck. But I’m really in a bind and forums just aren’t helping.
I’ll start with the truck.
01 cummins. 7x11 dap injectors. Promaxx head with heavy porting and #103 springs. 30% over so vp44. T4 manifold set up. Everything studded. Electronics I have the iQuad with v2 tuning.
Tranny is a full built 47re with a 300 drop triple disk converter. Ratchet shifter with standard valve body.
3:54 gearing.

I’m in the hunt for a new turbo. But I’m am stuck. I been looking at the s363/68 and 73. With a .91 housing. Or .80 gated.
My issue is I’m not so much worried about power as I am worried about egt. I have a hx40 with a turbine measuring 76x64 exducer. I have made a very small tune and I can still get 1500 egts in 7sec.
I am worried a s363 with the 68 exducer will not flow enough. And wondering if the 73 will?

I’m jumping to a whole new subject. But I been looking at a s464. And everyone talks bad on them on the vp44. But I can turn 4000 rpm. And was wondering if it could be a option?

I want to get a turbo that will get me a controlled 1200-1500 egts on my larger tune. And if I can get this. I will add water meth to help more.
The truck is a daily and pulls maybe 5 times in a yr. I’m mainly pulling loaders. Weighing 7-12k.

I know my power and boost won’t be there till 2000rpm with a s464. But I’m still worried a s363 or S364.5 with the 68 or 73 won’t support my egt issue. I would like 600hp one day but I’m not saying these turbos are gonna put me there with my mods. I just want them to be able to support that power and support the egts with it when that day comes.


Sent from my iPhone using Tapatalk

I’d be looking more toward a decent set of injectors.


Sent from my iPhone using Tapatalk Pro

And more timing up top if you aren't maxing timing be 3k or a little sooner.

I have timing at 23 at 3k.
V2 tuning this is my average timing I have set
14 at 1500
17 at 2000
21 at 2500
23 at 3000
26 at max. Which is for anything over 3000
What’s your thoughts?


Sent from my iPhone using Tapatalk

you want WAY more timing up top. stock tuning asks for ~25* at 3k rpm

15 at 1500
19 at 2000
24 at 2500
28 at 3000
30 at Max

Click to expand...

If the truck runs good at 2500+ rpm then increase timing even more. I am betting that you will see a signficant drop in EGTs.

The edge comp, and old Quadzilla tunes both max timing at 30* by ~2500-3k if boost is up.

I’ll give that a go. Thanks! But turbo will still need changed and wondering what you all think about the s363 or s364.5/73 .80 gated. Or a 68 exducer same housing?
.80 gated flows better then the .91 non gated right?


Sent from my iPhone using Tapatalk

I’d personally go with 63.


Sent from my iPhone using Tapatalk Pro

63/68 or 63/73?
So I turned the timing up and it definitely made a difference in egg and power. I can still get 1400 egt on my daily tune but turned all the way up. So it made a difference! I use to hit 1300 with the daily tune all the way down.


Sent from my iPhone using Tapatalk

I like smaller turbine wheel on VP trucks. Make use of that very limited RPM range.

That 73 will not be a good choice on a vp. 63/68/13 or 63/68/14 would be my choice.


Sent from my iPhone using Tapatalk Pro

YoungDiesel27 said:

I like smaller turbine wheel on VP trucks. Make use of that very limited RPM range.

Click to expand...

Reving 4K. Do u think I’ll choke it with a 68? I think I’m just really worried about flow. And I keep comparing the s363 to the hx40 I have. Which measures close to the 68 s363. But the BorgWarner may flow 100% better. Idk.


Sent from my iPhone using Tapatalk

phillherling10 said:

Reving 4K. Do u think I’ll choke it with a 68? I think I’m just really worried about flow. And I keep comparing the s363 to the hx40 I have. Which measures close to the 68 s363. But the BorgWarner may flow 100% better. Idk.


Sent from my iPhone using Tapatalk

Click to expand...

Revving and making power at 4K are different things.


Sent from my iPhone using Tapatalk Pro

I really appreciate all of you helping me.
I’m still learning the v2 and making my own tunes. And I’m happy that more timing drop the egts about 300 degrees. Now I still won’t turn on my bigger pump stretch tune and harder fueling because I know it will still hit 1600-1800 in about 5 seconds. But I’m considering the s363/73/.80 gated


Sent from my iPhone using Tapatalk

phillherling10 said:

I really appreciate all of you helping me.
I’m still learning the v2 and making my own tunes. And I’m happy that more timing drop the egts about 300 degrees. Now I still won’t turn on my bigger pump stretch tune and harder fueling because I know it will still hit 1600-1800 in about 5 seconds. But I’m considering the s363/73/.80 gated


Sent from my iPhone using Tapatalk

Click to expand...

Make the turbine choice from application that you will be using it for. If mainly daily or tow use I would give up a couple hundred rpm on the top for a couple hundred Usable rpm on the bottom.

Fueling falls off the face of the earth after 3500 rpm, nearly all vp44 applications have no need to turn more than 3500. The longer you are above 3400 rpm the more fuel the ecm is going to pull.

just a curious question...are you allowing the turbo to move the air ?

a lot of egt concerns are spikes or climbing of the egt, once you allow the charger to flow, they usually settle down some.