Y-Pipe or 3" cat-back?
 

Since I am on a budget like most people, which mod would I actually see a better gain with? They are about the same price... I eventually will do headers, but that is some time down the road. I have read alot about the Y-pipe giving big gains on the 5.5 Gen. Any info would help. Thanks.

Do the 3" exhaust you'll get more power with that verses the Y-pipe. IIRC you only get 7-10whp with the Y vs 15+whp with the 3" catback.

i didnt think you gained that much with a catback?

I don't know how much you can expect to get out of a 3" catback when using OEM manifolds. You get 15whp from a 3" catback WITH headers. fwiw I've only seen one dyno of the 3" showing that 15whp gain despite all the one recently purchased.

pass on the y and go 3". i dont know if anyone dyno'd the 3" on a car without headers, but with headers the gain on the 3" was nothing short of impressive..

Everyone is citing one dyno in support of 3" catbacks but have these results ever been duplicated since then?



Oh yea, y-pipe > 3" exhaust if you have to choose.

y pipe on an 02-03 is the worst bang for the buck mod..been there, done that..

So a $900 catback is going to be better?

i would def. go with the 3inch i had a 2 1/2 and swaped up to 3 and my power band was more consistant through rpms not to mention my low end got really nasty good for 20+ punch. and drop my et to 13.7 from a 13.9. not to mention it sounds so darn sexy...er

Does anyone have a dyno of a 3" catback with an otherwise stock exhaust providing huge gains?

well, since the OP is planning on getting headers in the future, IMO its silly to spend 300-400 on a y pipe.

i would like to see a dyno of this as well

i say if you plan on getting headers, it wouldn't be bad to get the 3" catback first instead of spending it on a y pipe.

if you don't plan on getting headers, get the y pipe.

If that's the case he should buy neither and just save up for headers. It would be equally silly to purchase a $900 catback as a first mod when the real restriction is still there. A catback is going to be virtually useless without some sort of header/y-pipe setup. It's like putting the cart before the horse.



And in case anyone forgot, the question he asked was what would provide more gains with his CURRENT mods. I think I answered that question fairly accurately.

You are correct. I appreciate all the responses. I was leaning towards the cat-back first, since I can add the headers later and not lose anything. But I read somewhere that the Y-pipe was a big power adder for the 5.5 gen... But then again, would headers alone give any real gains with stock cat-back?

Headers w/ stock catback > 3" catback by itself.

unless you think 5-7 hp is a lot, dont get the y pipe. i bought it years ago and it was not worth the 400 i spent. the y pipe doesnt remove precats, which is why it makes so little power. for the 400 bux, get the obx headers, thats the best you can spend for the $$. you will still gain horsepower with the stock exhaust and headers

That is what I was looking for, the single mod that will give the best gain. But I figured with stock exhaust the headers would serve no purpose. I may just do the headers then if I will gain more than cat-back by itself. Thanks for the info..

3" will also sound better..

ill be honest, if you have the budget at the moment is $900 i'd say buy the headers and get either a the 3" later... if the decision is only between the 3" catback and a y-pipe then the decision is way easy... The 3"

i agree, if you have the money then do the 3inch, if not do the headers. I myself got my 3inch custom for 250.00. i wanted to buy the complete system but it does not flow with the base of the bumper, and that really erks me, so i ended up goin to a really darn good shop and got a Borla psx 3inlet 2 2 1/2 out lets and i love it:D

I'll have this for you at some point in the future, but it might not be a fair comparison for those with just boltons. As mine will have a fully built motor in front of it, and the supporting mods alone would benefit it greater at that point.......I'm just saying. :D

honestly you are gunna feel a gain either way. I bet your not building a race car so 5hp difference is not going to be noticeable. so with what will be most noticeable and by that I mean physically!!! VROOM VROOM!! get the exhaust and stop wondering about a silly y-pipe you would rather do it while your up there with the headers. might as well wait and but the headers and y-pipe before you do that mod cause then you only have to work with that crap once instead of twice.

jake

3" catback > y-pipe all day on a 3.5.

So you guys are saying that a 3" catback w/ completely stock exhaust manifolds/y-pipe will provide more gains than an aftermarket y-pipe?? :confused:

If you plan on getting headers later I would go with the catback. Since you will get a ypipe with your headers there's no point in having 2 of them. headers=win... btw you can buy obx v2 headers for like $350 on ebay. IMO just skip ypipe and 3" catback, buy headers first they arent too expensive. That will be the biggest bang for buck ratio :)

So basically post #13? :)

Think you missed this part. :)

Oh yea......

And since we're on the topic of dyno evidence, can anyone provide me with one showing that a 3" catback with NO OTHER EXHAUST MODS will outperform a y-pipe? Thanks! :)

Details, schmetails...... :D

^Yeah Isn't that weird? +1^,
It's still unclear to me, if there is also a significant power increase during normal part throttle operation(the entire powerband) or is this increase in power just felt at WOT +4000 rpm????:confused: If I were you I would start with the headers first and work your way back....IMO if you install the 3" exhaust first, your gonna lose power since you'll breathing through the stock exhaust manifolds and precats...I wouldn't invest into a y-pipe if you plan on getting headers in the future...But the ypipe with intake are well proven to put down decent WHP!

THank you! Finally someone saw it. You can't put the cart before the horse

You have to open those headers/y-pipe up first before seeing any results with a 3" exhaust.

I can..........




























































not provide you with that :D