Not all parts are created equal. Learn from my mistake, and dont trust parts just by their name. I purchased a set of "billet" plenums from another diesel shop online because they were more expensive than Riffraff's and the pictures looked ok. Well it was a terrible mistake, they didnt have oring seal, only RTV, had cheap hardware store bolts instead of stainless, and the "machining" looks like it was done with a table top router instead of CNC. It was completely 1 dimensional an worse flow than stock. In the end I had to sell them on eBay just to get rid of them and purchased these from Riffraff Diesel. What a difference! The machining is amazing, exactly and off the charts on flow profile. If you are serious and want quality parts Riffraff is the only way to go. These guys are top notch and have the best customer service. I regret ever purchasing from someone else, I got bit and paid the price but hope that by sharing you wont and can learn from my mistake.

A repair shop recently damaged one of my plenums so badly, it was not reparable with riffraff insert rings. So I decided to spend a few bucks more and get the billet plenums.
Easy to install once you have everything cleared out of the way. The hardest part was the oring gasket if you can call that hard. Follow the directions, call riffraff if you questions and they will help pretty darn quick.
No more leaks, no one can damage them, no more blowby. Peace of mind.
My wife even likes them.
I notice a difference immediately!
Pull the trigger, you won’t be disappointed.

Instructions was a bit confusing. The instructions had tapered screws; these were allen heads with a shoulder. When I opened one bag of screws the allens were diffrent sizes from the second bag. The screw was the same size but the allen head was a diffrent size and the shoulder of the bolt was larger the torque specs were all the same. nobody can see them anyway. The plenums fit great heavy duty and look great to bad no one can see them.

I got the 2 inch plenums because I have an OBS 1997 Powerstroke. These things really are a work of art. They are very sturdy and well made, it gives me confidence knowing that these won't lift or leak when I throw boost to my engine. Thank you Clay for making the 2 inch ones for the OBS trucks, I am very happy with these.

Thank you Riffraff Kind regards from Australia.

The design and machining is quite amazing on these plenums. From the oring, to the stainless hardware, to the professional box that it comes in. 5 stars!

High Quality milling. Pay attention to the bolt lengths.... beatiful, Functional, durable.
Supa fast shipping. Thank you riff raff

I happen to be a machinist with 43 years in the trade. I have to say....These. Are. Beautiful.

The step over on some of the surfaces only add to the beauty.

I think the oring groove could use a few pinch points to hold the oring while installing...minor thing though.

Definitely buying these for my other 7.3's. They fit perfect and I love the way they look. It's a shame they're under so many lines and wiring.