upgrading a 2004 LS with the 3.4
#11
Also the MagnaFlow Downpipe through Summit Racing does not state whether the CAT is HI-Flow.... so I assume it is not.
#13
No, duals are not stock on the LS. Got a picture of your exhaust?
#14
Last edited by and.i.crawl; 10-23-2013 at 03:05 PM.
#15
Joined: Apr 2010
Posts: 12,262
From: Mentor, Ohio
I am not so sure the MagnaFlow pipe is equivalent to the ZZP pipe. The MagnaFlow pipe has a different style of flex joint that is restrictive down to a 2" ID..... which is not big deal seeing as the 2.5" pipe has an ID of 2.34 ID. The ZZP pipe has a braided flex joint, is it restrictive down to 2" ID?
Also the MagnaFlow Downpipe through Summit Racing does not state whether the CAT is HI-Flow.... so I assume it is not.
Also the MagnaFlow Downpipe through Summit Racing does not state whether the CAT is HI-Flow.... so I assume it is not.
I agree, if it does not say Hi-Flow on it, I would assume it's more to stock (again, not sure you can find a high flow off the shelf).
But I am suspecting if you're doing an exhaust, this will get a 3400 as close to a ZZP DP as possible (again, assumption).
#16
#18
Joined: Apr 2010
Posts: 12,262
From: Mentor, Ohio
If I were you, I'd put the cat/dp on the last of the list (since I don't believe any of them are high flow cats, performance gains are minimal). If you want to get rid of the U-bend, I would find an exhaust shop that can do the job, or buy ZZP's U-bend delete with rear O2 and gasket option (comes to $54, then again, just find a way to get it installed):
ZZPerformance - Ubend Delete #ZZ-UBENDD
Unless you find a DP with a high flow CAT, the U-bend delete and resonator deletes are the only exhaust options worth while. I don't know anything about the mufflers you have on the car, but I doubt you need to worry about them. Looks like it still has the stock Y-pipe which is fairly decent (especially for a non-boosted car).
Going back to my original list, here's what I would do if I were you...
Definite items to do:
- CAI (Wizaird or Cold Air Inductions are two good brands)
- L67 Coils (these are the coil packs found on the 3800 Supercharged engine, I would not recommend paying more then $30 for a set).
- Resonator delete
If you want to take additional steps, these would be more the "optional list" (as I think the gains are limited):
- U-Bend delete (either by itself or if you find a bolt on downpipe with a high flow cat, for the cost of a regular cat, if it's not broken, I don't see the value).
- If you can't find a Downpipe with high flow cat, see if you can have a shop cut you current cat and weld in a high flow.
- CAT back exhaust (more for change in the exhaust, if you buy a kit, you may be able to find one with a resonator delete as part of the kit).
- A basic PCM re-tune
Another item for the exhaust, not sure if they make headers that fit the 3400 in a W-body (Monte). I know they do for the Grand Ams, even thought the engine is the same, not sure if they have any fitment issues on the Monte due to different chassis and transmission. But if they did, that might make a good mod.
The reason I put the PCM optional is that all these mods will help in small increments but should not do anything requiring a PCM re-tune. All the would do is potentially optimize them a little more (but again, they are nothing drastic). But there is a lot a tune can do done by someone who knows what they are doing with this car and drivetrain.... They can tweak some items and probably get the transmission to give you more of a "punch" feel (plus remove the speed limiter and delete the P0420 code if you get a high flow cat).
I hope this has not confused anything. I guess what I'm trying to say, start with what I listed as "Definite items to do" and then see what you think of it so far and if you wish to go further. The best part of this mod list, the only part I would say do LAST is if you decide to do anything with the PCM, outside of that, nothing is dependent on what order you do them in.
ZZPerformance - Ubend Delete #ZZ-UBENDD
Unless you find a DP with a high flow CAT, the U-bend delete and resonator deletes are the only exhaust options worth while. I don't know anything about the mufflers you have on the car, but I doubt you need to worry about them. Looks like it still has the stock Y-pipe which is fairly decent (especially for a non-boosted car).
Going back to my original list, here's what I would do if I were you...
Definite items to do:
- CAI (Wizaird or Cold Air Inductions are two good brands)
- L67 Coils (these are the coil packs found on the 3800 Supercharged engine, I would not recommend paying more then $30 for a set).
- Resonator delete
If you want to take additional steps, these would be more the "optional list" (as I think the gains are limited):
- U-Bend delete (either by itself or if you find a bolt on downpipe with a high flow cat, for the cost of a regular cat, if it's not broken, I don't see the value).
- If you can't find a Downpipe with high flow cat, see if you can have a shop cut you current cat and weld in a high flow.
- CAT back exhaust (more for change in the exhaust, if you buy a kit, you may be able to find one with a resonator delete as part of the kit).
- A basic PCM re-tune
Another item for the exhaust, not sure if they make headers that fit the 3400 in a W-body (Monte). I know they do for the Grand Ams, even thought the engine is the same, not sure if they have any fitment issues on the Monte due to different chassis and transmission. But if they did, that might make a good mod.
The reason I put the PCM optional is that all these mods will help in small increments but should not do anything requiring a PCM re-tune. All the would do is potentially optimize them a little more (but again, they are nothing drastic). But there is a lot a tune can do done by someone who knows what they are doing with this car and drivetrain.... They can tweak some items and probably get the transmission to give you more of a "punch" feel (plus remove the speed limiter and delete the P0420 code if you get a high flow cat).
I hope this has not confused anything. I guess what I'm trying to say, start with what I listed as "Definite items to do" and then see what you think of it so far and if you wish to go further. The best part of this mod list, the only part I would say do LAST is if you decide to do anything with the PCM, outside of that, nothing is dependent on what order you do them in.
#19
Joined: Apr 2010
Posts: 12,262
From: Mentor, Ohio
Hey, hey, I forgot a shop to consider.... Milzy Motorsports. I believe they do a bit more with the Grand Ams, but they also work with the W-bodies. They have a stainless downpipe with u-bend delete and state it's a high flow cat. Here's the link:
MMS Stainless Downpipe for 3100 and 3400 powered 97-03GP/00-05MC/Imp - Milzy Motorsports
A high flow cat does add some value to the process. On my 3800, I did not notice a HUGE change, but I did notice a little change (in the end for me, it was part of a larger formula of mods later down the road that I needed anyways).
But these guys would be a good group to ask if you could get N-body/Grand Am headers to work on a Monte.
If you wish to go any "wilder", Milzy is a shop that offers a lot more for a 3400. You could either get a kit or junk yard pic and do a 3500 top swap (heads, LIM, UIM from a 3500, I don't know how the throttle body is adapted in that as the 3500 is drive by wire, but I'm sure these guys can do it). Again, a bunch of different options to spend money lol.
MMS Stainless Downpipe for 3100 and 3400 powered 97-03GP/00-05MC/Imp - Milzy Motorsports
A high flow cat does add some value to the process. On my 3800, I did not notice a HUGE change, but I did notice a little change (in the end for me, it was part of a larger formula of mods later down the road that I needed anyways).
But these guys would be a good group to ask if you could get N-body/Grand Am headers to work on a Monte.
If you wish to go any "wilder", Milzy is a shop that offers a lot more for a 3400. You could either get a kit or junk yard pic and do a 3500 top swap (heads, LIM, UIM from a 3500, I don't know how the throttle body is adapted in that as the 3500 is drive by wire, but I'm sure these guys can do it). Again, a bunch of different options to spend money lol.
#20
Where would I find the l67 coils? all ive found is conversations on various forums comparing stock l67 coils to msd saying msd/aftermarket are worse but ccan't seem to find anything other than conversations on forums
also seeing a lot of people saying changing them ouwon't matter and its just a gimmick? Is that because they have the l67 motor and they are discussing upgrading them to aftermarket
also seeing a lot of people saying changing them ouwon't matter and its just a gimmick? Is that because they have the l67 motor and they are discussing upgrading them to aftermarket
Last edited by and.i.crawl; 10-23-2013 at 10:35 PM.