Headers with Cats - ZR-1 Net Registry Forums

32valvZ · 09-08-2018

So I mocked up the headers with the Magnaflow cats.... I got a couple of issues...

Theyre too long when put together and I wont be able to bolt the exhaust up with them in place. I got the shortest ones I could find.... still too long.

Im not sure but I think I will have to bolt it all up w/o the cats and bring it to a shop to cut and weld.... problem is, I will loose the offset I need to mate up to the exhaust if I just weld the cat onto the collector. Not sure how to approach that....

Any suggestions or good pics of how some of you handled this problem, if you had this problem,,,

Thanks!

Paul Workman · 09-08-2018

Quote:

Originally Posted by 32valvZ

So I mocked up the headers with the Magnaflow cats.... I got a couple of issues...

Theyre too long when put together and I wont be able to bolt the exhaust up with them in place. I got the shortest ones I could find.... still too long.

Im not sure but I think I will have to bolt it all up w/o the cats and bring it to a shop to cut and weld.... problem is, I will loose the offset I need to mate up to the exhaust if I just weld the cat onto the collector. Not sure how to approach that....

Any suggestions or good pics of how some of you handled this problem, if you had this problem,,,

Thanks!

I'm not exactly clear what you're referring to - except the pipe leading to the rez (or X-pipe) will not fit, no? That shouldn't be a tough problem for any muffler shop worth their salt to fab up a new section or modify the existing piece.

What is the "CAT BACK" system you have now?

32valvZ · 09-08-2018

Mornin' Paul...

So the cat back is unknown. Resonator is gone, and has 2 through pipes where it was. The X pipe is forward of that, then the 2 normal pipes that are needed to connect the left and right sides one with the "ball socket" (if thats the correct term), then the passenger side with the flat mating surface using the gasket.

Everything will go together , unless I put the cats in place.... then the headers and cats are too long and I cant bolt anything up after the cats.

What I mean by offset is the passenger side has an offset to it that is lost because the bullet cats are not offset in any way.

last time around on my 92 I didnt use cats and there was no issue... this time.. I need to use them. Wife cant hardly take the fumes now even with factory cats... its pretty rich when cold. She has pretty bad asthma... but she loves going for drives and driving the Vette. Id like to be able to include her.

Ccmano · 09-08-2018

Installing the cats generally requires some cut and paste. Take it to a muffler shop and have them do it if your not comfortable cutting the exhaust system. The cats need to go as close to the engine as possible. I had to fab up some adaptor pipe and trim the exhaust system to fit it together. It’s not plug and play unless you get a full header/exhaust system like Stainless Works.
H

09-08-2018	#1
32valvZ Join Date: Nov 2007 Location: Sunshine State Posts: 1,071	Headers with Cats So I mocked up the headers with the Magnaflow cats.... I got a couple of issues... Theyre too long when put together and I wont be able to bolt the exhaust up with them in place. I got the shortest ones I could find.... still too long. Im not sure but I think I will have to bolt it all up w/o the cats and bring it to a shop to cut and weld.... problem is, I will loose the offset I need to mate up to the exhaust if I just weld the cat onto the collector. Not sure how to approach that.... Any suggestions or good pics of how some of you handled this problem, if you had this problem,,, Thanks! __________________ [B]1990 #2815[/B] [COLOR="Red"][B]Red/Red[/B][/COLOR] Ported Plenum & IH (by Pete) Haibeck Chip Rebuilt FPR (by Phil) FIC Injectors Watson LT Headers 3" Stainless Works exhaust Lingenfelter Open Air Lid Bill B Built Transmission Shifter & C Beam Plates [FONT=Impact][COLOR=red]1992 [COLOR=black]#[/COLOR] 091[/COLOR][/FONT] [FONT=Impact][COLOR=#ff0000]Red/[COLOR=silver]Gray[/COLOR][/COLOR][/FONT] [B]SOLD[/B]

09-08-2018	#3
32valvZ Join Date: Nov 2007 Location: Sunshine State Posts: 1,071	Re: Headers with Cats Mornin' Paul... So the cat back is unknown. Resonator is gone, and has 2 through pipes where it was. The X pipe is forward of that, then the 2 normal pipes that are needed to connect the left and right sides one with the "ball socket" (if thats the correct term), then the passenger side with the flat mating surface using the gasket. Everything will go together , unless I put the cats in place.... then the headers and cats are too long and I cant bolt anything up after the cats. What I mean by offset is the passenger side has an offset to it that is lost because the bullet cats are not offset in any way. last time around on my 92 I didnt use cats and there was no issue... this time.. I need to use them. Wife cant hardly take the fumes now even with factory cats... its pretty rich when cold. She has pretty bad asthma... but she loves going for drives and driving the Vette. Id like to be able to include her. __________________ [B]1990 #2815[/B] [COLOR="Red"][B]Red/Red[/B][/COLOR] Ported Plenum & IH (by Pete) Haibeck Chip Rebuilt FPR (by Phil) FIC Injectors Watson LT Headers 3" Stainless Works exhaust Lingenfelter Open Air Lid Bill B Built Transmission Shifter & C Beam Plates [FONT=Impact][COLOR=red]1992 [COLOR=black]#[/COLOR] 091[/COLOR][/FONT] [FONT=Impact][COLOR=#ff0000]Red/[COLOR=silver]Gray[/COLOR][/COLOR][/FONT] [B]SOLD[/B] Last edited by 32valvZ; 09-08-2018 at 09:40 AM.

09-08-2018	#4
Ccmano Join Date: Jun 2006 Location: Sparks, NV Posts: 2,852	Re: Headers with Cats Installing the cats generally requires some cut and paste. Take it to a muffler shop and have them do it if your not comfortable cutting the exhaust system. The cats need to go as close to the engine as possible. I had to fab up some adaptor pipe and trim the exhaust system to fit it together. It’s not plug and play unless you get a full header/exhaust system like Stainless Works. H __________________ 90'ZR-1 #1461 Red/Black Ported Intake, Degreed Cams, OBX Headers & Exhaust, Fidanza FW, Secondary Delete, Custom tune, C6 GS Wheels. Sold 08 C6 Z51 Crystal Red Metallic Sold Vararam Intake, Tune, Sold 05 C6 Z51 Red/Black Sold 90'ZR-1 #1723 Black/Gray Sold but not forgotten 91' Z51 L98 White Vert. My First, you always remember your first. Sold.