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Old 10-23-2017, 11:22 AM   #1
gable74
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Exhaust Manifold Flange Size

He guys,
I bought some after market Rams Horn manifolds last year and just got around to installing them this weekend. They were pretty easy to install and everything went smooth. I am dropping the truck off at the exhaust shop Friday to get the tubes ran. I have some quiet Walker mufflers to hand over but I do not have the collector flanges that bolt to the manifolds. They looked like they were the ball type flanges. I am not an exhaust expert so I am trying to figure out if....

- There is a difference between the donut type and the ball type flanges?
- What size is the flange? 2.5"?
- Would a decent exhaust shop already have what they need to transition from
the manifold to the pipes?

I plan on calling them in a little bit to verify some of these questions but I wanted to see what you all had to say too.

Thanks,
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1971 K2500 Custom Camper (Sold)
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Old 10-23-2017, 11:53 AM   #2
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Re: Exhaust Manifold Flange Size

Looks like the flange on the manifolds is a 2.5" and donut style. Can I use a standard reducer flange with a donut? Something like this?

https://www.summitracing.com/parts/big-10005flt
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Old 10-23-2017, 08:37 PM   #3
B. W.
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Re: Exhaust Manifold Flange Size

No - leakage will occur!

I used a pair of Walker 41248 elbows coupled with Walker 31883 flanges & Fel-Pro 60986 donuts. I sawed up the elbow to get the desired fit

The exhaust should be able to form the end for the donut and the elbow.
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Old 10-23-2017, 11:45 PM   #4
gable74
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Re: Exhaust Manifold Flange Size

Thanks for the info!

How much of this should a decent exhaust shop be able to handle. I feel like the flared tube at least should be able to be fabled up in the shop. I will pick up the donuts and rings just to be safe.
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Old 10-24-2017, 10:05 AM   #5
B. W.
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Re: Exhaust Manifold Flange Size

A decent shop should have (or have quick access to) any part needed to make your exhaust. Post up some pics when done!
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Old 10-24-2017, 11:39 AM   #6
gable74
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Re: Exhaust Manifold Flange Size

Will do....thanks.
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