jr27

ok, im finally ready for my next mod. i am not sure which one is best to do first, im debating on if i should do the pcd or j-pipe first. what do you guys think? i am eventually gonna do them both but i can't do them both at once, i just put some wheels and tires so i do not have that money to drop at once. i want to know which of the two you guys think would make the most power gain by itself, i only have a cai other than that my 2005 a/t engine is stock. also what j-pipe will be best. thank you guys in advance.

MurkyRiversTL

PCD first and youre gonna bottle neck to the stock j pipe then third cat. J pipe first and youre gonna bottle neck to the third cat.... lose lose situation unless you get the race pipe for the third cat, or HFC for the third cat.

But... out of the two, I believe the PCDs give better performance gain.

Tmarks91

Oh ya PCD's By far! best bang for your buck... Jpipe u wont really actually notice physical gains mostly all mental but for PCD's you will for sure notice perfomance low end and high end

Slooo97CL

iTrader: (1)

PCds cost less too, how are the cali emissions test going to work out for you with PCDS?

justnspace

iTrader: (1)

Not if you get the RV6 V3 jpipe. it comes with longer primaries deleting the 3rd cat all together.
but then you just bottle neck after that.

jr27

haha yeah cali emissions are SUPER strict but around my area there are a few shops i know of that ok your car for a little extra money, thats how i have been doing my truck for years now.

jr27

thank you guys so much for the input. i just wish i could get them both at once but i have to wait a little bit. well i guess i might go with the pcd's, but do you think it will be bad for my engine if i only do that and then i bottle neck the rest of the exhaust like a few of you stated above? and also would i need any special tool or help for the pcd's? the j-pipe i know only takes a few minutes ive done it on other cars but never the pcd's. thanks again.

justnspace

iTrader: (1)

i think a lot of people are scared of the word bottle necking.
NO, it wont hurt your engine.
understand how exhaust gasses flow.
its like a 4 lane highway merging into a two lane highway with traffic.
what do you get? bottle necking!
you'll still get to your destination, only slower.


its obviously better to have your exhaust free flowing and open (think of the 4 way highway.)
but its okay to have it go from 4 lanes to 2 and or vice versa.


I have the RV6 V3 Jpipe and I'm running great!

7.5AV6MT

I think your best bet is to wait a little longer and save up for both. You'll save money buying them as a package from RV6, and also save a bit on the install cost.

MurkyRiversTL

OntheJob

For clarification, with this situation you stated, the advertised 10-15 HP will still be picked up by adding the J-pipe to the stock exhaust correct?

jr27

wow i felt like a kid being thought something new but it worked thanks man.

jr27

yup i know but i know that if i keep waiting im gonna spend the money on other things, i recently bought wheels when they were not even next on my list. i bought the new navi disc update and it wasnt on my list either so i feel that if i can buy these piece by piece i will get them sooner. and on the install, i am planning to do it myself. well if its not to hard, i have done a couple of bolt on exhausts on other cars but never messed with any pcd's hope its not too hard.

justnspace

iTrader: (1)

Please, clarify your clarification.
what is the advertised 10-15HP?

I think you mean PCDS.

this is what the stock exhaust system looks like....
pre-cats-->Factory j-pipe-->3rd cat-->mufflers.

going back to my analogy....when running stock you're in a 2 lane highway. No doubt you'll get to your destination.

when adding aftermarket parts, is when we open up that highway.

PCD's-->Aftermarket J-pipe--> aftermarket mufflers.

the RV6 jpipe takes out that 3rd cat.
you just shortened the destination and widened your lanes. Making the exhaust flow faster and quicker.

SharksBreath

iTrader: (33)

^well said.

OntheJob

the Rv6 Jpipe, dyno charts show a 10-15 horsepower increase by adding the Jpipe alone. Its on his site and original thread.

MrHeeltoe

iTrader: (1)

I say J-pipe first (ATLP) and a Race pipe if you want to delete the cat. To avoid emissions problems you could also consider the ATLP Metal cat for the 3rd cat.

This isn't completely true. There is not any such thing as bottle necking unless you are going to a transition that REALLY impacts flow. Going from 2.5" to 2.25" or 2 3/8" is not a bottle-neck. Going from 2.5" to 1.5" is. There are gains to be had in replacing any single item alone due to the volumetric increase in that section of the exhaust. All the parts will work together so to get most power you'd need all 3. But for a first part, I'd go J-pipe. RV6 for Max power, ATLP for optional cat and more subdued sound.


The J-pipe does provide REAL gains. The PCDs, while they do gain a lot, have serious smog implications for some people, change the exhaust note more than some might like, and make the exhaust literally stink. Great mod, but be careful recommending the benefits without the side effects.

Excelerate

iTrader: (1)

If bottle necking were the major concern then technically you're hitting a bottle neck with the factory j-pipe, factory third cat, and factory exhaust. Either way you're going to have some sort of bottle neck unless you replace all the components. That being said, I would be leery of replacing your primary emissions filter on your vehicle; it's one thing to eliminate the third cat since you the pre-cats do most of the filtering but to eliminate the primary cats is a questionable mod, at least to me.

The j-pipe is a great first starting mod. Of course we recommend our XLR8 j-pipe since it has equal length runners and it is made out of T304 in the US.

http://store.excelerateperformance.c.../i-236895.aspx

jr27

thank all you guys again for all the replies. i came a ccross a fellow member here of the site that messaged me about his v2 rv6 pcd's that were ceramic coated does this improve any gains or what benefits does it have.

justnspace

iTrader: (1)

I know its on his thread, I was asking you to clarify what you meant. the PCDS and Jpipe both show a 10-15whp increase. so thats up to 30 horses.

and again, i do have the RV6 V3 j-pipe installed.

MurkyRiversTL

There are all types of bottles with different size necks.... bottle necking is more of a generalized statement defining the change of flow caused by a reduction in the size of the path the flow is taking....

MrHeeltoe

iTrader: (1)

Just because there is a change in flow does not mean the same volume is not getting though. Smaller diameter has a faster flow, larger is slower. That is my point, the same as yours...only a drastic size difference is going to cause an "issue".

A bottleneck would be an area where flow is inhibited or restricted. I don't think you are going to run into inhibited or restricted flow with any combo of the parts mentioned. You can't get any more restricted that you will with the stock stuff...therefore any upgraded part only serves to improve performance.

MurkyRiversTL

I see your point, in fact, we are arguing the same point. Depending on the speed of flow, even small amounts of restriction can cause a slower speed of flow. I guess we would really have to take into consideration the velocity of the flow compared to the diameter changes.

Although the Jpipe does get rid of that nasty T that the stock unit has.... at any point, getting rid of the stock j pipe would be extremely beneficial.

OntheJob

Very cool! Hey by any chance do you have those set up with a stock exhuast.. Im curious to hear if and how the exhuast note changed.. I dont like the sounds of after market FULL exhuast from front to back. How would you compare?

justnspace

iTrader: (1)

yes, i have only modified my jpipe. everything else is stock.
there is no change in sound.
maybe at wot when in Vtec, it sounds akin to a CAI.
but at idle and normal driving, there is no change.

if i dont mention that I changed the jpipe no one would ever know.

MurkyRiversTL

^ Would you even know?

justnspace

iTrader: (1)

on the sound? no.

OntheJob

Perfect, and exactly what Im looking for... sleeper.

MurkyRiversTL

Performance??

justnspace

iTrader: (1)

I have a 6M/T.
when it was first put on, yes. 1st and 2nd gear, the power delivery is more linear. also top end increased. 80-120MPH is awesome.
but now....not so much. I've gotten used to the feeling.

I would like to line up against a stock TL 6M/T and a type-s Auto to see how well the jpipe did.

MAS

iTrader: (3)

I've had both (V3 J-pipe & V2 PCD).......having said that, i would get the PCD's first because the power gain is freakin awesome.

Souljah

PCD without a doubt.
Trust me son.

MurkyRiversTL

^ I didnt know you guys were related...... he should have taken your fatherly advice a while ago

Tmarks91

http://www.youtube.com/watch?v=UEGlxNQj-Ck video of my car after i got my pcds installed

jr27

i think im gonna get pcd's first but now i just have one more question. my goal is to get the whole rv6 exhaust, pcd, j-pipe, and dual cat back. my issue is that i have heard and read forums that say that pcds and j-pipe together will give you a nasty rasp. i know the solution is to put a resonator somewhere but if i dont like the rasp and later i want a resonateor will it fit somewhere with the whole rv6 set-up finalized. thanks guys.

dragonsking91

would the PCD and RV6 V3 jpipe make crazy rasp sound? I hear if you go with PCD then u should add a high flow cat to minimize the rasp sound alone with burn gas smell. It is true? I'm thinking of doing the same set up but worry about the sound and the smell. thank