12v exhaust manifold questions.

[Landmissile]

Tried searching but I keep getting links to patent info.

Trying to find out if there are different model exhaust manifolds for the 12v Cummins. I picked up a new HX40W turbo with the impression it was a factory replacement. Clearly I was wrong. Looks like my turbo has a 3 inch flange for the down pipe but opens up to 4 inches. The HX40W has a 4 inch flange. That's not an issue. The issue is the exhaust manifold flange. The HX40W flange is quite a bit larger.

Is there a factory manifold that will fit the HX40W?

[Landmissile]

Did a search for HX40 and found better info.

[DodgeFreak]

you might have a t4 flange on the turbo and factory is t3 on the manifold for our trucks.

[thrashingcows]

There is T3 to T4 flange adapters available.

[Landmissile]

Appreciate the follow ups. I found the info I was looking for here on 1st Gen after searching under HX40. My truck has a T3 flange on the manifold. The turbo I got does have a T4 flange. It looks like the Cummins with California emissions may come from the factory with a T4 flange on the manifold and a port for the EGR valve. I haven't been able to completely confirm that though so don't hold me to it.

I decided to keep the T4 HX40 turbo after finding a simple 1/2in adapter. Ordered a 4in V band kit for the down pipe as well. Doesn't look like the turbo is the best one to have but I got it for cheap and my truck won't ever see any heavy towing... ever again. I'm pretty sure I won't be barking the turbo either... whatever that means. LOL I'll likely add an intercooler a little later as well. Now I'm just waiting for the rest of the small parts and I can bolt it all together. Maybe I'll even pass the emissions test and finally get it registered.

[bmoeller]

Passing an emissions test with a HX40? Good luck with that.

[Landmissile]

Passing an emissions test with a HX40? Good luck with that.

Man I hope you're kidding. I just committed to this stupid turbo last night. Why would the HX40 cause it to fail? Everything I read made it sound like a "barely worth the time" upgrade. I'm not trying to get crazy with performance upgrades on this thing, just want it to be 100 percent for the test and for use. Would I be better off testing it on the old to worn out OEM turbo?

[RCCUMMINS89]

Because they are a big laggy terd of a turbo.

T4 manifolds do not belong on a 1st gen truck.

Want to pass emissions.... put it to stock and then go from there.

[Landmissile]

put it to stock and then go from there.

Yeah... thought that's what I was doing from the beginning, I was seriously misinformed. Appreciate everyone's feedback.

[Landmissile]

Ok... I "might" be able to salvage this. I have an opportunity to get an HX35 in exchange for the HX40. It's also new and has a T3 flange for what it's worth. Would it be better to trade the HX40 for the HX35? From what I've been reading in my search here the 35 would be better for my stock engine. Will the 35 pass my stupid emissions test?

For the record... in this last week I've learned more then I've never wanted to know about turbos for these trucks. I'm not complaining but my head hurts all the time now. Should have done all this research before I pulled the trigger. Lesson learned. Just want some guaranteed success for the next test.

[RCCUMMINS89]

Stock engine, 35 will be perfect.

[fatty]

T4 manifolds do not belong on a 1st gen truck.
.

Ain't nothing wrong with t4 turbos. They're cheaper usually and make power just fine. I can peg my speedo in under a 1/4 mile with my "laggy pile of turd t4 turbo". Tell me that's not making good power.

[Landmissile]

Stock engine, 35 will be perfect.

That's awesome. I'm calling the guy right now. Really appreciate the quick reply. Can't wait to get this done and put it behind me.

Now for a question of much less importance. The same source that told me the HX40 would be a good replacement for the stock turbo also said it would be good to add an intercooler to my truck. Seems like it would be good in concept but now I feel like I should question everything. Is it worth the trouble to add an intercooler? Would an intercooler cause the truck to fail emissions?

[Landmissile]

T4 manifolds do not belong on a 1st gen truck.
.

Ain't nothing wrong with t4 turbos. They're cheaper usually and make power just fine. I can peg my speedo in under a 1/4 mile with my "laggy pile of turd t4 turbo". Tell me that's not making good power.

Well crap! LOL What turbo are you running with the T4?

[fatty]

I got a 63/68/.83. It's laggy for sure, don't get me wrong. But for the way I use my truck it works just fine. I never drive in traffic, mostly on rural roads so the lag doesn't bother me.