6.1 LJR Build

Another day of “taking it easy” miles just to make sure everything is working correctly. Seems funny to say when yesterday it was run up to 120+ on the dyno. Anyway, other than adding a high flow cat, the only thing I’ll need to address is the thermostat. Someone may have mentioned it earlier but I’ll need to change to a 180. Right now it’s a 210 I believe and we’ve got the controller on the fan turned wide open so the fan pretty much never shuts off. We’ll make the change next week and that should fix the problem. Other than that, just trying to figure out some characteristics of this setup and remembering 6th gear doesn’t exist anymore.

Yeah, I've got the 180° thermostat with mechanical fan and it runs right at 183°. I'm guessing you have the 201° thermostat.
I've got 2 Flow Master high flow cats on my install and by looking through them I can't imagine them having any restriction at all.
 
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Yeah, I've got the 180° thermostat with mechanical fan and it runs right at 183°. I'm guessing you have the 201° thermostat.
I've got 2 Flow Master high flow cats on my install and by looking through them I can't imagine them having any restriction at all.

Is that the ideal operating temp for the Hemi? On my LS I'm reading that I want it to run hotter than that. It's still in the crate so it hasn't been an issue though.
 
Is that the ideal operating temp for the Hemi? On my LS I'm reading that I want it to run hotter than that. It's still in the crate so it hasn't been an issue though.

I run the 180 in mine, but it's tuned at that temp. I ran the 210 when I first put the thing in, and had some overheating issues which were not directly related to the thermostat. I swapped in the 180 as part of everything else I did at the time. The under hood temps were out of control with the 210 though. I've had no issues with running the 180.

It may be different with your newer LS, Ryan.
 
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I run the 180 in mine, but it's tuned at that temp. I ran the 210 when I first put the thing in, and had some overheating issues which were not directly related to the thermostat. I swapped in the 180 as part of everything else I did at the time. The under hood temps were out of control with the 210 though. I've had no issues with running the 180.

It may be different with your newer LS, Ryan.

Jeff, I knew you changed stuff around with yours but couldn't remember which way. Figured I'd ask.
 
Is that the ideal operating temp for the Hemi? On my LS I'm reading that I want it to run hotter than that. It's still in the crate so it hasn't been an issue though.

So, from what I can remember when I was doing all the research on this swap, I was understanding that the hemi was designed to run optimal right at about 200°. I had also learned that in the considerably smaller under hood area that it caused the engine to run a little hotter than it does in the trucks. So I bought both 180° and 195° thermostat and decided to start with the 180° thermostat and see how that works. The hottest outside temperature that I've had it running so far has only been about 65°, so I'm going to wait and see what kind of temperatures I get out of it when it's in the 80s or '90s and if it still stays in the low 180° mark then I may swap to the 195° thermostat.
As a reference my 2018 RAM truck with the 5.7 hemi runs at 203°, no matter what the outside air temperature is.
 
Anyone have any suggestions on a good high flow cat?

Yep, I used 2 of those in the 100 GPI index and they are almost empty inside. I would guess no restrictions at all.

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Same type I used on my exhaust. I'm running 3" diameter exhaust. I'm amazed you fit two of them on yours.

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Sometimes I amaze myself, but very rarely do I amaze my wife.
I wasn't sure if I was going to be able to get both of them to fit but they just barely did. They are two and a half inch pipe size and 4-in diameter overall size, and I think about 9 in Long.
 
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Sometimes I amaze myself, but very rarely do I amaze my wife.
I wasn't sure if I was going to be able to get both of them to fit but they just barely did. They are two and a half inch pipe size and 4-in diameter overall size, and I think about 9 in Long.

I think this Hooker setup is 3.25?
 
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Also make sure to check the Grid Per Inch rating on them. The lower the number, the less restrictive they are. I think factory cats are 400 and high flow are 100-200. The ones I used are 100 GPI.

I think I have the 200 GPI on mine.
 
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The main goal is to eliminate smelling the fumes but it’s also the first attempt at quietening it down a little. It’s just a little too loud in the cab. Some have said a high flow won’t help with sound and some have said it will. Won’t know till it’s on. But again, sound isn’t the main goal.
 
The main goal is to eliminate smelling the fumes but it’s also the first attempt at quietening it down a little. It’s just a little too loud in the cab. Some have said a high flow won’t help with sound and some have said it will. Won’t know till it’s on. But again, sound isn’t the main goal.

Yeah, I really don't think the high flow cat will do anything for the sound, but definitely will clean up the exhaust.

Did you happen to get any time to take some oil filter pictures yet?
 
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Yeah, I really don't think the high flow cat will do anything for the sound, but definitely will clean up the exhaust.

Did you happen to get any time to take some oil filter pictures yet?

O crap! Totally forgot man. I’m in Charlotte till Sunday night but I’ll get some for you Monday when I’m back at the shop.
 
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Yeah, I really don't think the high flow cat will do anything for the sound, but definitely will clean up the exhaust.

Did you happen to get any time to take some oil filter pictures yet?

Daubie - have you looked into using the angled filter adapter out of a Ram? That’s what’s in mine and it clears everything.
 
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