RAM RHO HO Downpipes with High Flow Cats +100hp!

Chris3058 · Feb 10, 2026

Following.

26Blkrhino · Feb 10, 2026

What exhaust are people running with these down pipes?

D&Sadventure · Feb 10, 2026

DBallz is running stock with a set stainless brothers resonators installed in a straight section of the exhaust.

Bananarocket · Feb 15, 2026

So I finally got around to giving this a skim a few days ago.

Forgive me prior to getting an rho I wasn't a big car guy and not familiar with a lot of this stuff but...

Is the big advantage here is less so peak horsepower (albeit, it's not nothing) but more so getting some pretty significant increases in horsepower and torque at much lower RPMs? Sounds pretty cool beans.

Bananarocket · Feb 15, 2026

DBallz said:
Solid peak gains as well as great power improvements across the RPM range. Peak torque is delivered almost 300 rpm sooner with massive bottom end gains.

Stock vehicle (red) vs the addition of PSP Fat Cat down pipes (blue).

View attachment 19753

Once again I'm a nub... but why does the chart for stock start at higher rpms (~2800ish vs ~1800ish for down pipes)?

PinnacleBuilt · Feb 17, 2026

Bananarocket said:
Once again I'm a nub... but why does the chart for stock start at higher rpms (~2800ish vs ~1800ish for down pipes)?

because I'm not driving on the dyno. I talk about it somewhere in this thread.

RB72 · Mar 1, 2026

Any updates when these will be shipping out?

Thanks

RamFan · Mar 1, 2026

RB72 said:
Any updates when these will be shipping out?

Thanks

I don’t know but someone on the facebook forum is already claiming he has a set. But there are liars all day long looking for attention.

Chris

26Blkrhino · Mar 7, 2026

Posting for a follow up. Anyone gotten them?

Slotrx · Mar 7, 2026

Ordered mine a little over a month ago but was told 6-8 weeks so we will see if they are on time

Santino · Mar 8, 2026

Slotrx said:
Ordered mine a little over a month ago but was told 6-8 weeks so we will see if they are on time

They have been taking orders for 6-8 months without a single person posting of delivery...I hate to be the wet blanket.

26Blkrhino · Mar 8, 2026

Santino said:
They have been taking orders for 6-8 months without a single person posting of delivery...I hate to be the wet blanket.

That’s what’s got me hesitant.

PinnacleBuilt · Mar 19, 2026

Everybody waiting on orders.

GOOD NEWS!!!

After what seems like an eternity, 8 boxes of cnc mandrel pipes are on the way.

Also new cnc vband flanges are now being included as an upgrade at no charge. Less turbulence, better flow, better seal and much easier install. These vbands are $110 each to machine (massive chunk of billet 304 stainless) but super sweet.

att.DxRSWL4wQH9oUhzLm-Y_5tdkLO53gN5RpfZK9NbqBLo.webp

We’ll be in the jig and tig stage soon and building based on order dates.

MurderedCat · Mar 19, 2026

DBallz said:
Everybody waiting on orders.

GOOD NEWS!!!

After what seems like an eternity, 8 boxes of cnc mandrel pipes are on the way.
View attachment 27435
Also new cnc vband flanges are now being included as an upgrade at no charge. Less turbulence, better flow, better seal and much easier install. These vbands are $110 each to machine (massive chunk of billet 304 stainless) but super sweet.

View attachment 27436 View attachment 27437
View attachment 27438
We’ll be in the jig and tig stage soon and building based on order dates.

What was final price on these?

PinnacleBuilt · Mar 19, 2026

MurderedCat said:
What was final price on these?

PSP Fat Cat

Brendandaly85 · Mar 19, 2026

I'm not an expert on reading dynos so forgive my ignorance here:
It looks like strong power gains on the low end of the RPM range, but significant drop off (underperforming stock levels) as you get to 4k+ RPMs? Is this an accurate interpretation of the results?

Scottie2Hottie · Mar 19, 2026

Brendandaly85 said:
I'm not an expert on reading dynos so forgive my ignorance here:
It looks like strong power gains on the low end of the RPM range, but significant drop off (underperforming stock levels) as you get to 4k+ RPMs? Is this an accurate interpretation of the results?

Negative. Look at the graphs again. RED is stock, BLUE is with DPs. The follow each other across the graph but notice the BLUE is above the RED across the RPM range.