ARH LTH questions

[Ramitiner]

Ok guys, so im going to get some ARH LTHs by the end of the month and want to make sure im getting the one I need. my truck is a '17 CC 4x4 with the 5.7 and A8 trans, my supporting mods right now are fastman TB, vararam, carven competitor (noise), pedal commander and I do have an unlocked PCM and a diablo tuner. I do plan on going cammed later on as well but MIGHT consider a SC. I haven't gotten a custom tune yet because was waiting on the LTHs... anyway now that ya know what I got, here is my question.. I got two years before my next inspection so Im thinking of going catless and then get the catted pipes later on...or I can go catted now and stay that way. IF I go the catted route I know it will be more restrictive so do I go with the 1 7/8 version to offset that restriction? let me hear your suggestions please.

 

[Wild one]

Ok guys, so im going to get some ARH LTHs by the end of the month and want to make sure im getting the one I need. my truck is a '17 CC 4x4 with the 5.7 and A8 trans, my supporting mods right now are fastman TB, vararam, carven competitor (noise), pedal commander and I do have an unlocked PCM and a diablo tuner. I do plan on going cammed later on as well but MIGHT consider a SC. I haven't gotten a custom tune yet because was waiting on the LTHs... anyway now that ya know what I got, here is my question.. I got two years before my next inspection so Im thinking of going catless and then get the catted pipes later on...or I can go catted now and stay that way. IF I go the catted route I know it will be more restrictive so do I go with the 1 7/8 version to offset that restriction? let me hear your suggestions please.

You didn't hear this from me,lol.Some guys have been known to hollow out the cats or modify them to utilize a straight through pipe.That way it still looks like the cats are in place and functioning to pass a visual inspection,that's if your smog inspections still do a visual check.

 

[Ramitiner]

You didn't hear this from me,lol.Some guys have been known to hollow out the cats or modify them to utilize a straight through pipe.That way it still looks like the cats are in place and functioning to pass a visual inspection,that's if your smog inspections still do a visual check.

I hears ya. I'm new to Jersey but I'm pretty sure they do a visual... That's why I'm saying I can just go one size up and negate the restriction from the cat... Makes sense to me, lol

 

[Wild one]

I hears ya. I'm new to Jersey but I'm pretty sure they do a visual... That's why I'm saying I can just go one size up and negate the restriction from the cat... Makes sense to me, lol

I don't know if going up in header size before the cats will actually offset the cats.The cats are only going to flow so much volumn,no matter the size of the pipe ahead of them. Actually a smaller primary might force more volumn through them then the bigger primary pipe will,the smaller primary tube will help keep the velocity of the flow up compared to the larger primary tube,at least that's the way i'd look at it,but then again I'm only guessing to,lol

 

[ramportin1]

Honestly good high flow cats now days can easy keep up with a built hemi. You'd be just fine even if you threw a sc on.

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[ramportin1]

Look at the hellcat it has cats

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[Ramitiner]

Look at the hellcat it has cats

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Yea but a hellcat without cats would be less restrictive, no?

 

[Ramitiner]

I don't know if going up in header size before the cats will actually offset the cats.The cats are only going to flow so much volumn,no matter the size of the pipe ahead of them. Actually a smaller primary might force more volumn through them then the bigger primary pipe will,the smaller primary tube will help keep the velocity of the flow up compared to the larger primary tube,at least that's the way i'd look at it,but then again I'm only guessing to,lol

I'm going with the understanding that if the primaries go up in size then the cats would also follow suit, no? Otherwise the extra size of the primaries would automatically get cancelled out by the cats

 

[Triumphx]

Go with 1 7/8 if you plan on boost, if not 1 3/4.

 

[crackerjack1957]

If you worried about cat restriction all you got to do is spend the extra $650 & buy the catless mid/y pipe.
Swap them out & the other tune you will need when inspection time comes around.......some cash, work & time involved but if that's what you want go for it.

 

[Ramitiner]

That's an option... Just but the catless and in 2 yrs for my next inspection get the catted one... So again... 1 3/4 or 1 7/8

 

[VB712]

If you are 100% going to supercharge it, do the 1 7/8th. If not, stick with 1 3/4

 

[Ramitiner]

If you are 100% going to supercharge it, do the 1 7/8th. If not, stick with 1 3/4

Nothing is 100%. I definitely want to do a cam first and then a Sc

 

[crackerjack1957]

Nothing is 100%. I definitely want to do a cam first and then a Sc

Cam will not get you to 500HP.......so I would stick with 1 3/4 if you are not planning on going over that with nitros or boost.
Its been said several times already.....only you can decide what you want.

 

[Ramitiner]

That's cute, you quoted what I wrote and then only commented based on half of it... I said cam first. Now, my question continues to be how much tq loss Is there with the 1 7/8 until or if I go SC? The obvious reason for the question is so I don't have to buy one and then the other later.

 

[Wild one]

Nothing is 100%. I definitely want to do a cam first and then a Sc

Ramitiner have you looked into these yet,there's a few outfits that make dummy cats,and they might be something to consider in your case.

http://www.siliconeintakes.com/prod...d=320&osCsid=d0b9101b28fa71b3d25ecbefbe23103e

 

[Wild one]

That's cute, you quoted what I wrote and then only commented based on half of it... I said cam first. Now, my question continues to be how much tq loss Is there with the 1 7/8 until or if I go SC? The obvious reason for the question is so I don't have to buy one and then the other later.

I run 1 7/8's JBA's on my nitrous'd toy,and even off the bottle on a soft nitrous tune,they're still livable with my 1.5HL Greene cam/84mm true bore Fastman throttle body etc.. Look at Stainless Works headers they are reportedly an equal length primary pipe'd header,and might be a better option then the ARH's in your case.

 

[Ramitiner]

Ramitiner have you looked into these yet,there's a few outfits that make dummy cats,and they might be something to consider in your case.

http://www.siliconeintakes.com/prod...d=320&osCsid=d0b9101b28fa71b3d25ecbefbe23103e

People are so smart! Lol

 

[Ramitiner]

I run 1 7/8's JBA's on my nitrous'd toy,and even off the bottle on a soft nitrous tune,they're still livable with my 1.5HL Greene cam/84mm true bore Fastman throttle body etc.. Look at Stainless Works headers they are reportedly an equal length primary pipe'd header,and might be a better option then the ARH's in your case.

Hey brother, you say it's livable... Is the tq loss noticeable from stock with those on your tune without the juice?

 

[Wild one]

Hey brother, you say it's livable... Is the tq loss noticeable from stock with those on your tune without the juice?

Honestly in my opinion it gained a bunch of torque on the bottem end compared to the stock log manifolds.I wouldn't worry to much about either size headers,they'll both blow the stock manifolds into the weeds as far as grunt goes. Way back when my truck was a little closer to stock,i was running a Diablo 93 canned tune and the stock manifolds,the truck was running low 14's with a best of a 14.19,threw the big JBA's /catless midpipe on it and had a custom datalog tune done,the truck went from low 14's to mid 13's with a best of a 13.4,admittedly the tune did help,but the headers were also a lot of the gain.That was with the stock cam and just a CAI and Magnaflow catback behind the catless mid pipe.