Opel GT Forum banner
1 - 13 of 13 Posts

·
Opeler
Joined
·
38 Posts
Discussion Starter · #1 ·
I think I was about to make a big mistake. I have what I believe is a standard center muffler, resonator and over axle pipe for a 73 GT. I have the 2.2FI with the original exhaust manifold. My car is at the local exhaust right now. It wa suppose to be done today but when I checked on it he said he won't get to it until tomorrow. I was reading a thread about this type of exhaust system and that it will choke the engine. Can anyone suggest a suitable setup from the manifold back that I could use and get fairly quick. I will ask the shop manager also but I would like to have a small clue about what I'm looking for. I am under a real time constaint right now. I only have about 4 or 5 days left before I must head out of Dodge. I need to have the car at the paint shop before I leave. I don't want to over spend but I do have a small swell in my pockets to burn.

Arnold
 

·
Opeler
Joined
·
38 Posts
Discussion Starter · #2 ·
I've been reading the thread on what nobody is doing. And I guess I will try to get the exhaust shop to do a down pipe that collects at 2" and go with a turbo muffler that will take 2" then straight back with 2" and see if the shop can modify my resonator to take 2" and do 2" out tail pipes. Besides that I have no other ideals. Not like that one was mine:rolleyes:

Arnold
 

·
Registered
Joined
·
216 Posts
I tried one of those "Pep Boys" turbo mufflers and it sounded like krap...I think I would just fine a short regular muffler designed for 2" exhaust...
 

·
Opeler
Joined
·
1,303 Posts
I have a 2.2 engine in my GT and need to get it in for an exhaust overhaul as well. From what I’ve read, and from direct advice from other owners that have a history with these cars/engines....for a 2.2+ engine it should be 2”-2 1/4” exhaust from the header to a muffler (straight through if you don’t want any restriction), then 2 1/2” over the axel to accommodate for pipe bends restricting the flow, then in to a Y for the two tailpipes.
Some owners have used two mufflers, one in front of the axel and another after the axel, but space & aesthetics can be an issue. It comes down to sound and flow for performance...and what your driving needs are. From what I have researched and gathered (which doesnt make it true!) i believe a smaller diameter exhaust will aid low end performance but can increase drone and exhaust flow/scavenging. As with everything, there is give and take and you have to know what you are after.

I personally have a new Sniper unit on my rebuilt 2.2 and don’t do much high RPM driving, and when I do it’s just on the highway at cruising. I don’t want exhaust drone like I have now when on the highway, so that’s a goal of mine when I have my system done. I’d like a little rumble at idle but I don’t want it to sound loud or like a sup’d up civic. I’m planning to go either 2” or 2 1/4” for what I have. I’ll lean on the shop to help fine tune (no pun intended) the sound and flow.
 

·
Opeler
Joined
·
1,303 Posts
Here are a few old exhaust focused threads, but I don’t think all that much has changed over the years....so they all contain helpful info.



 

·
Opeler
Joined
·
1,303 Posts
I tried one of those "Pep Boys" turbo mufflers and it sounded like krap...I think I would just fine a short regular muffler designed for 2" exhaust...
So, I JUST realized that I responded (TWICE!) to a SUPER old thread because there was a new post on this today. Now I feel crazy for scrambling to find some answers for the original poster. Hahah! I gave myself a good chuckle when I checked in on things just now.
 

·
Just Some Dude in Jersey
Joined
·
15,468 Posts
Yuk! Yuk!

Good you found out, I was about to post a response, too.

I'll do it anyway:
One my normal cammed 2.4 I use 2 1/4" stainless piping throughout, with a stainless Flowmaster, a split Y with no resonator, and high quaility tips. Best sounding exhaust I've ever had. Goes fast, too.

:)
 

·
Opeler
Joined
·
1,303 Posts
I would like to know if there’s a recommended size exhaust pipe for each size of motor (1.9, 2.0, 2.2, 2.4) and driving style (low rpm torque, high rpm, etc), but modifications obviously make it tough. We’ve read so many accounts of different sized systems being put on GTs with different size motors causing power gains or power losses/restrictions.
I know @RallyBob has mentioned dyno losses for different brands of mufflers before in some threads. I’d like to know how to find out what’s “ideal” for specific motor sizes and driving habits. Probably a quest that won’t be fulfilled though
 

·
Registered
Joined
·
30 Posts
Yuk! Yuk!

Good you found out, I was about to post a response, too.

I'll do it anyway:
One my normal cammed 2.4 I use 2 1/4" stainless piping throughout, with a stainless Flowmaster, a split Y with no resonator, and high quaility tips. Best sounding exhaust I've ever had. Goes fast, too.

:)
How is the sound of Flowmaster? I'm planning to order one from 4wheelonline because I want to make my exhaust louder but without creating a drone.
 

·
Registered
Joined
·
1,475 Posts
glaspak and toner tip go for it
 

·
Opel Rallier since 1977
Joined
·
2,278 Posts
2" for the 1.9/2/.0 and 2.25" for the 2.2/2.4L. This has been posted.

For info, I went from 2.25" to 2.5" for a turbo'd 2.6L engine (aproximately 275 peak HP) and found an improvement; it might benefit from 2.75" at that engine size + turbo flow. I just threw that out there to give some frame of reference for the 2" and 2.25" for the smaller, non-turbo displacements; those sizes are plenty big enough to not be any significant restriction.

I put a Dynomax on my Ascona A with 2" piping on the 1.9L with no resonator, and it seems OK to me for drone factor. (And yes my hearing is good! LOL) But I have not driven in on a long trip either so the jury is out on that. I look for a muffler like that that has a non-straight-through flow, i.e., where the flow has to make a couple of turns inside the muffler.
 

·
Registered
Joined
·
893 Posts
I had a 2" system with 2 straight through mufflers in my ex 2,2 liter Kadett C and can say that it definitively wasn't the cork in the system. An engine doesn't care what diameter the exhaust is as long as it flows enough.
 

·
Registered
Joined
·
574 Posts
I only have about 4 or 5 days left before I must head out of Dodge. I need to have the car at the paint shop before I leave. I don't want to over spend but I do have a small swell in my pockets to burn.

Arnold
Moderators are going to have a real problem if you keep talking about the small swell in your pants.:ROFLMAO:
 
1 - 13 of 13 Posts
Top