exhaust dilemma, let me know what you think

**mpfranks** · 12-16-2008, 10:11 PM

ok so heres the deal. i have a 2000 ws6, with a gmmg catback and slp ypipe. last year i bought the slp ypipe to replace my stock one without thinking long term for headers. however, now i bought qtp longtubes, but havent put them on yet.

the problem is the collectors on the headers are 3", and the inlet and the outlet on the slp ypipe is 2.5". also, i know that the slp ypipe wont fit without being modified.

is it gonna be a problem that i go from 3" collector, to a 2.5" ypipe, back to a 3" catback? will this cause power loss?

am i better off to just shell out the extra $300 for the qtp ypipe? or will i be ok with cutting off the flanges on the slp and fitting it to the qtp headers?

thanks for the input.

**sunsetorangess** · 12-17-2008, 01:12 AM

To save time and a headache i would go ahead and spend the extra cash to get the Qtp Y pipe.
J

**SSwt00SS** · 12-17-2008, 05:00 AM

just get a 3" y-pipe, sell off the SLP y-pipe and get some $$$ back...

**side2000** · 12-17-2008, 06:05 AM

you're flirtin with one hellofa mess there. yes, flow characteristics will be all outta wack with that bottleneck in the center of your exhaust, if you could even pull that off. buy a new one.

**Firebirdjones** · 12-17-2008, 07:32 AM

I agree,,,you are going to go through some headaches trying to match that up,,,and spend some money on fab work too. I'm willing to bet with fab work labor, flanges and extra tubing you would be close to buying that 3 inch Y-pipe anyway.

I would make the plung and save the headache. You'll be happier in the long run.

**BIG GUNS** · 12-17-2008, 01:27 PM

I wouldn't even deal with it. I would just get a 3" y pipe to match and be done with it.

When I have enough, I'm going to get the LPP set up with the matching y pipe.

**0rion** · 12-17-2008, 02:14 PM

I agree with everyone else. Buy the 3" Y and sell the SLP to recoup some of your money. I can tell you from experience that by the time you fab it up you'll have the money in it to have bought the 3" Y. I run into this everytime I do exhaust work. I do it to try and save money and by the time it's all said and done I could've taken it somewhere and not had the headaches.

**Too Fast** · 12-17-2008, 02:37 PM

Yup + however are above. Just get the matching 3" ORY and be done with it. Problem solved.

**01ws6er** · 12-17-2008, 05:44 PM

Either buy ad new 3" ORY or have an exhaust shop fab one up for you.

**mpfranks** · 12-18-2008, 11:49 AM

well i guess ill add it to the wishlist.

thanks for the input guys.

**Too Fast** · 12-18-2008, 07:45 PM

**hot93rod** · 12-19-2008, 10:37 AM

just to go ahead and beat a dead horse here, i am in a similar situation where my cat back is a 2.5, and my y forward is a 3 i believe... I'm in the same boat w/everyone else, and i'd say it is better to go all one size

**allbaugh_04** · 12-23-2008, 09:00 PM

Yea, everyone said it already, but i will share my opinion as well. You definetly don't want a smaller y-pipe in the middle of your exhaust.

You don't necessarily have to buy the QTP ypipe either. The exhaust shop might have what you are looking for, or they can make you one....then sell the SLP one.

**9t8z28** · 12-25-2008, 05:27 PM

Originally Posted by mpfranks

ok so heres the deal. i have a 2000 ws6, with a gmmg catback and slp ypipe. last year i bought the slp ypipe to replace my stock one without thinking long term for headers. however, now i bought qtp longtubes, but havent put them on yet.

the problem is the collectors on the headers are 3", and the inlet and the outlet on the slp ypipe is 2.5". also, i know that the slp ypipe wont fit without being modified.

is it gonna be a problem that i go from 3" collector, to a 2.5" ypipe, back to a 3" catback? will this cause power loss?

am i better off to just shell out the extra $300 for the qtp ypipe? or will i be ok with cutting off the flanges on the slp and fitting it to the qtp headers?

thanks for the input.

Get rid of the SLP Y-pipe and get the QTP/Flowmaster Y-pipe ONLY if you have access to a welder OR, get the Pacesetter Y-pipe for around $150, trim 2" off of the front of it and have it re-expanded then put it on and connect it to your GMMG.

**mpfranks** · 12-28-2008, 10:39 AM

Originally Posted by 9t8z28

Get rid of the SLP Y-pipe and get the QTP/Flowmaster Y-pipe ONLY if you have access to a welder OR, get the Pacesetter Y-pipe for around $150, trim 2" off of the front of it and have it re-expanded then put it on and connect it to your GMMG.

is that what you did? how did it work out? why whould you need to cut off 2"?

if there is any fab work involved that puts me right back in the same boat. id be better off just getting the qtp since its a direct fit.

**9t8z28** · 12-28-2008, 10:45 AM

Originally Posted by mpfranks

is that what you did? how did it work out? why whould you need to cut off 2"?

if there is any fab work involved that puts me right back in the same boat. id be better off just getting the qtp since its a direct fit.

Yes, I used the Pacesetter Y-pipe w/ my QTP longtubes. The Y is designed for there headers which are shorter.

Like I said, you are going to need to weld and possible do some trimming on the QTP/Flowmaster Y-pipe to make it fit correct. It is much easier chopping off 2" off of each side of the Y and then having it re-expanded.

Here it is installed.

**mpfranks** · 12-28-2008, 10:57 AM

Originally Posted by 9t8z28

Yes, I used the Pacesetter Y-pipe w/ my QTP longtubes. The Y is designed for there headers which are shorter.

Like I said, you are going to need to weld and possible do some trimming on the QTP/Flowmaster Y-pipe to make it fit correct. It is much easier chopping off 2" off of each side of the Y and then having it re-expanded.

well i like that too cuz its $200 cheaper. well what about if i wanted to add cats to that? you think adding universal cats would cause anymore problems? i really dont want to run cats, but in ohio in my county we have e-check. and i cant apply for collector plates yet. if not, i might have to register it in another county.

yeah that looks clean, that what i was worried about. i see you didnt use the clamps that come with the pacesetter.

how do you like your qtp's? i cant wait to install mine

**9t8z28** · 12-28-2008, 11:02 AM

Originally Posted by mpfranks

well i like that too cuz its $200 cheaper. well what about if i wanted to add cats to that? you think adding universal cats would cause anymore problems? i really dont want to run cats, but in ohio in my county we have e-check. and i cant apply for collector plates yet. if not, i might have to register it in another county.

Yes, you can add cats to it. The passenger side will be a little easier then the driverside.

**9t8z28** · 12-28-2008, 11:04 AM

Originally Posted by mpfranks

well i like that too cuz its $200 cheaper. well what about if i wanted to add cats to that? you think adding universal cats would cause anymore problems? i really dont want to run cats, but in ohio in my county we have e-check. and i cant apply for collector plates yet. if not, i might have to register it in another county.

yeah that looks clean, that what i was worried about. i see you didnt use the clamps that come with the pacesetter.

how do you like your qtp's? i cant wait to install mine

No, I used band clamps. They are great. If you use the U-bolt clamps that come with the Pacesetter Y, you will never get it apart again.

The QTP headers are great. Perfect fit and very durable. They are basically the same as Kooks but they are polished.

**mpfranks** · 12-28-2008, 11:06 AM

Originally Posted by 9t8z28

Yes, you can add cats to it. The passenger side will be a little easier then the driverside.

from the pictures it looks like it would be the othe way around

yeah my girlfriend worked at summit racing, so i got the qtp's since they carried them. i got them for $500 instead of $750. couldnt pass it up.