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Diamondeye exhaust

J

jrsavoie

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Rural Clifton, Illinois
I just installed a 3" diamondeye downpipe on the 1994 today.

I noticed the flange that goes to the turbo was considerably smaller outside diameter that the downpipe that was previously on there and smaller than the old OEM that I have in the shed.

Is that going to cause me issues?
It looked like the clamp CX aught all the way around. But I don't know it it centered properly.
 
ak diesel driver said:
IIRC the old OEMs were double wall so unless you measure the ID..........
Click to expand...
I'm not following you.

I'm talking about the outside diameter of the flange that the turbo clamps to.

The OD of the flat ring that goes to the turbo and holds the downpipe to the turbo.

The diameter is smaller than any other I've seen.
By maybe 1/4" to 3/8"
This isn't what I have. Just thought I might clarify what I'm trying to ask

1023diesel.com

BD Diesel - Downpipe Kit - S400 4in Aluminized Full Marmon 4.2 (1045240) | Universal

BD Diesel - Downpipe Kit - S400 4in Aluminized Full Marmon 4.2 (1045240)
1023diesel.com 1023diesel.com
 
I had gotten the diamond eye 4" kit from summit for my tuck before they stopped making them. the down pipe was a 3" but I didn't have any issues attaching the flange to the turbo. I didn't compare the OEM one ether to see if there was any difference.
 
dbrannon79 said:
I had gotten the diamond eye 4" kit from summit for my tuck before they stopped making them. the down pipe was a 3" but I didn't have any issues attaching the flange to the turbo. I didn't compare the OEM one ether to see if there was any difference.
Click to expand...
I just noticed when I put it up there that it was considerably smaller than the outside of the turbo flange.
 
Makes me wonder if what you got is actually from diamond eye and not a china repop. before you connect the down pipe to the rest of the exhaust, grab the end and give it a good shake. see if it moves around the flange clamp. if it does move, then it will vibrate it's self loose over time.

on those type of flanges, I have seen folks use a flat lead gasket in there to take up a slight amount of space making the clamp tighter when torqued down. I have also seen those V clamps where one side of the clamp is slightly larger to cover for a smaller OD. those clamps only go on one way and can't be flipped around.
 
dbrannon79 said:
Makes me wonder if what you got is actually from diamond eye and not a china repop. before you connect the down pipe to the rest of the exhaust, grab the end and give it a good shake. see if it moves around the flange clamp. if it does move, then it will vibrate it's self loose over time.

on those type of flanges, I have seen folks use a flat lead gasket in there to take up a slight amount of space making the clamp tighter when torqued down. I have also seen those V clamps where one side of the clamp is slightly larger to cover for a smaller OD. those clamps only go on one way and can't be flipped around.
Click to expand...
It came from Heath.
He was the only one that had one at the time.
Wish I hadn't ordered it now.

It's been a while and the rest of the exhaust fell off while I was putting this on.

I was going to check into the 4" stainless that was posted about, awhile back
 
Will L. said:
Please explain- trying to learn exhaust materials. Failures, etc.
I thought y’all bought 304 stainless in rusty areas and it is good to go for 30 years?
Click to expand...
The previous owner installed a 4" aluminized system

The down pipe rusted off a few years ago.
The pipe that connected the down pipe to the muffler fell off in one piece. There was a thin piece about 1/4" wide left holding it.

The hanger was holding the muffler up. It came down easily.
I didn't mess with the tail pipe.
Had I installed it, it would have been stainless.

Even though sellers in Texas swore they never had an issue with aluminized.
 
Ok- aluminized not stainless. The difference in cheap stainless vs 304 stainless- I have seen in semi trucks that come through here. The real 304 stainless holds up for hears and the cheap stainless rusts, but not as fast as aluminized.

I wonder how galvanized pipe like electrical EMT compares to aluminized. I wonder if it is same thing.
Could be I already own some 4” emt (about 18’) and 4 each of the 90° sweeps us sparkys use for big wires. There was a good sale price of the 90s, and I knew a guy that had excess 4” stuff so I bought it and it awaits my mig welder.
Just not sure it will be worth the effort in the end…

I know 4” is definitely the way to go. Just not sure if me chopping and welding it all up is worth it depending how long it will last.


Sorry, just kills me that less material (shorter truck) that price is over double for incomplete system- and over triple price for stainless and thats to have 3.5” instead of 4” all just for the “hummer tax”.
 
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I would think, in your area, anything would last longer than we will.

What do you think about the undersized flange ?

When I get to taking it apart again, I will get measurements.

Hopefully not terrible far into the future.

I just installed a 3" diamondeye downpipe on the 1994 today.

I noticed the flange that goes to the turbo was considerably smaller outside diameter that the downpipe that was previously on there and smaller than the old OEM that I have in the shed.

Is that going to cause me issues?
It looked like the clamp Caught all the way around. But I don't know it it centered properly
 
What our friend from Ak was saying is- the factory pipe is actually a pipe inside a pipe.

So while the outside of the pipe looks really large- when you look inside it is small.
I would have to see the diamond eye you have to see if they are any different than they used to be, but they are usually larger than original by a ways
 
Will L. said:
What our friend from Ak was saying is- the factory pipe is actually a pipe inside a pipe.

So while the outside of the pipe looks really large- when you look inside it is small.
I would have to see the diamond eye you have to see if they are any different than they used to be, but they are usually larger than original by a ways
Click to expand...
The OD of the flat/ slightly concave flange that the clamp goes around doesn't really have anything to do with the diameter of the pipe.

The others were big enough to hold the pipe centered.

This old one measures 3-5/8. The one on the truck is lucky to measure 3-1/2"

Since that's a weldit, it seems that measurement would be the same, regardless
 

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