Cummins 4BT & Diesel Conversions Forums banner
1 - 16 of 16 Posts

·
Registered
Joined
·
120 Posts
Discussion Starter · #1 ·
Ok I'm the dummy here. Could someone give me an explanation as to how exactly these should fit up?

I've measured 3" for the flange on the back of my H1C turbo. Does that mean I need a 3" clamp?

I'm thinking that I need to have a maybe 2.75" downpipe to have a flange at 3"? With a 3" downpipe the two mating up looks like this.

And that doesn't look like a v-band clamp would do anything on that kind of joint.

I'm getting confused because the exhaust I bought has a 3" downpipe and the place I bought it from said it takes a 3" clamp. That doesn't seem right to me.

My main problem is that I bought this engine without a downpipe and I've never seen what the connection should look like. Plus it doesn't help matters that the clamp that I did buy looks like it is a 3.5" clamp not a 3".

Thanks :beer:
 

·
Registered
Joined
·
4,090 Posts
You need to get a v clamp and exhaust flange ( it loooks a double flare ) and that it welded to a straight section of pipe.So you'll need to cut off that flare off your pipe.Then weld on the flange and bolt it will bolt uo to your turbo.


www.airflow.com

exhaust flange 6bt # AD311


CrewCab59
 

·
Registered
Joined
·
713 Posts
That flange looks like it's been corroded off!

If you can't get anything to work just buy a V-band kit with 2 flanges and weld a flange to the pipe and to the turbine housing.

I hope you're not using that turbine housing though that thing looks like shit.
 

·
Vendor
Joined
·
2,697 Posts
You need to get a v clamp and exhaust flange ( it loooks a double flare ) and that it welded to a straight section of pipe.So you'll need to cut off that flare off your pipe.Then weld on the flange and bolt it will bolt uo to your turbo.


www.airflow.com

exhaust flange 6bt # AD311


CrewCab59
Where in this site do you go? Didnt have part search or part # search. Thanks
 

·
Registered
Joined
·
120 Posts
Discussion Starter · #6 ·
So would this flange do the same as the one previously posted?
http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=ATP-FLS-012&Category_Code=ATP-FLS1

I'm still trying to figure out if a 3" downpipe needs a 3" v-band clamp or bigger. The description of the one from ATP says its for a 3" tube and uses a 3" v-band clamp. The outlet of the turbine housing measured 3" across the flange. That would tell me that it needs a smaller than 3" clamp and flange.

Am I right or am I way off? I wish I would have just gotten the downpipe cutoff with the clamp on the engine so I'd know for sure.

Thanks for the help guys
 

·
Registered
Joined
·
1,068 Posts
That ATP flange is machined stainless and will work. The Airflo flange works as well and is exhaust tubing with a double flare of sorts, it is exactly what the early Dodge diesel had on it, I can't say for sure on 2nd Gens and up.
 

·
Registered
Joined
·
1,068 Posts
3" flange = 3" tube and uses a 3" v-band clamp, if you want to go bigger after that you need a transition piece. A section expanded to whatever size your going next.
 

·
Registered
Joined
·
278 Posts
I'm not sure what size mine should be either. The exhaust housing is #3521934 and the numbers 18 27 12 are also on it. The inside diameter of the exhaust is 2.5, the bottom of the flange recess is 2.75, and the outside diameter of the flange is 3.0 inches. The inside diameter of a 2.5 inch pipe is 2.375, so i think I need a 2.75 inch pipe. Is that not correct?
 

·
Registered
Joined
·
1,068 Posts
You need a pipe flange that matches the turbine housing flange, and whatever pipe matches the pipe flange...

The one and only way to size a turbine housing easy is to look into one of the two exhaust runners, there is an inverted or indented casting in there, that is the size in square centimeters. 16 = 16cm2 for example. It's in there, flashlight and rag with brake clean etc.
 

·
Registered
Joined
·
278 Posts
Thank you. I'll check on it tomorrow.
 

·
Registered
Joined
·
1,068 Posts
Here's another little tidbit to consider. One of my favorite exhaust pro's here told me that a mandrel bend exhaust tube will flow approximately 20% better than the common crimp bend pipe. So if you think 4" is excessive or are tight for clearance, I would consider a 3" or 3.5" with all mandrel bends. Also, Stans Headers, which happens to be one of two or three places to get a 4" mandrel bend downpipe for a 1st Gen Dodge Cummins, one of the guys there told me the Donaldson muffler they sell with their systems outflows a straightpipe system. That's on their flow testing so take it for what it's worth. I have the p/n if anyone is interested, it's a big one though... I build my own exhaust but I did use a muffler, the one they use. The noise is too much for wifey and the neighbors.
 

·
Registered
Joined
·
44 Posts
Proper V-Band Clamp for H1C

I'm having a hard time finding an online source for the correct v-band clamp for a H1C turbo. I have a couple of different 3" v-band clamps from different projects, but neither fit the turbo correctly. Could someone point me in the correct direction? Thanks
 

·
Registered
Joined
·
4,090 Posts
I'm having a hard time finding an online source for the correct v-band clamp for a H1C turbo. I have a couple of different 3" v-band clamps from different projects, but neither fit the turbo correctly. Could someone point me in the correct direction? Thanks
Post up some pics of the clamps you have ,what problem are you having turbo or exhaust? I never had any problem getting the right clamp.

Scott
 

·
Registered
Joined
·
120 Posts
Discussion Starter · #15 ·
Unfortunately I don't have any pictures of what I actually put together to fit but I do remember what stuff I bought.

This is the flange I used for the downpipe

This is the V-band clamp I used

The problem I was having is that I was measuring the largest diameter on the flange which was 3". I should have been measuring the minor diameter which was 2.5". Once I figured that out I smacked myself in the head a few times and went on with my life :)

Hope this helps ya out.
 

·
Registered
Joined
·
915 Posts
My turbo had the same outlet and I had to make the flange. While there is probably one made, I ended up using one like in your first pic but cutting it down. I could not find a 2.75" flange, but did find the clamp okay. It leaks a little bit from not being perfectly flat, but did pull up tight.
 
1 - 16 of 16 Posts
Top