406 Update
Moderators: MostMint, wxo, Fred32v, Basement Paul, ttamrettus
- TireSmoker
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I'm gonna 2nd what BP says. If you're not gonna open the headers, go with a 3". If you want to go 2.5", get cut-outs. I have zero complaints with mine. They're usually good for .2-.3 in ET. This also lets you err on the side of quiet mufflers for better street cruising.
X-pipes always seem to sound cool. I'd like to have one on my car.
-Dave
X-pipes always seem to sound cool. I'd like to have one on my car.
-Dave
Pipes
Well, it's already been purchased. It's 2.5in, mandrel bent, no cutouts. Oh well.
The existing mufflers are 2.25in and salvageable - and will be re-used, initially. Just a matter of $$$. The mufflers are Dynomax, Super Turbos. I kinda like 'em. I have the same on the Avalanche. So far, no plans for tail pipes, just gona dump out in front of the axle, with turn downs.
The existing mufflers are 2.25in and salvageable - and will be re-used, initially. Just a matter of $$$. The mufflers are Dynomax, Super Turbos. I kinda like 'em. I have the same on the Avalanche. So far, no plans for tail pipes, just gona dump out in front of the axle, with turn downs.
-Mark
2024 Equinox LT AWD
2015 Yamaha FRJ
2024 Equinox LT AWD
2015 Yamaha FRJ
Fit and Finish
Headers and this car, just suck.
I started on the drivers side, and after removal of the oil filter, center link and pitman arm, (for the install), I have a 'slight' interference at the transmission. Being a TH400, and the headers were probably designed for a 'glide or 4gear, I have to trim a tab, at the converter cover.
On the bright side, I visually checked the head port-to-header match, using the header gasket as a template, the match looks dam good.
I started on the drivers side, and after removal of the oil filter, center link and pitman arm, (for the install), I have a 'slight' interference at the transmission. Being a TH400, and the headers were probably designed for a 'glide or 4gear, I have to trim a tab, at the converter cover.
On the bright side, I visually checked the head port-to-header match, using the header gasket as a template, the match looks dam good.
-Mark
2024 Equinox LT AWD
2015 Yamaha FRJ
2024 Equinox LT AWD
2015 Yamaha FRJ
Exhaust Extraction
Both sides are in, although not permanently yet. Still test fitting.
The drivers side needed some massaging to clear the steering gearbox. The pass side had chassis and idler arm 'mount' issues. I'm shooting for 1/16in clearance to allow for engine movement and epansion.
OK, this is the third set of headers for this car, and I've yet to be mpressed.
Have I mentioned, headers for this car suck....
The drivers side needed some massaging to clear the steering gearbox. The pass side had chassis and idler arm 'mount' issues. I'm shooting for 1/16in clearance to allow for engine movement and epansion.
OK, this is the third set of headers for this car, and I've yet to be mpressed.
Have I mentioned, headers for this car suck....

-Mark
2024 Equinox LT AWD
2015 Yamaha FRJ
2024 Equinox LT AWD
2015 Yamaha FRJ
- Basement Paul
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- Location: In the dirt.
Headere Wrap
I haven't heard any really good things about wrapping headers. The header manufactures warn against it.
So, no, I won't be wrapping my headers.
So, no, I won't be wrapping my headers.
-Mark
2024 Equinox LT AWD
2015 Yamaha FRJ
2024 Equinox LT AWD
2015 Yamaha FRJ
Headers
Headers for this car, still suck.
But at least, they're in - hopefully for good.
Starter is back in, wired and tested. Steering is back in place too. I'm about half way thru plumbing the oil cooler. Plumbing at the grill end, will be interesting. Rad and fan are still out, as I'm still working on the oil cooler. Plug wires will have to be updated. Looks like my 135 deg ends won't work to well with the headers. Drivers side looks like 180s will work nicely, but the pass side, front two, cyls 2 and 4, will probably need 90s. 6 and 8 will probably work with 180s. Tranny lines are still off. Tranny filler tube is still out too.
A preliminary mock up of the X pipe, looks like she'll have to make a trip to the muffler shop. This aint gona be a bolt on.

But at least, they're in - hopefully for good.
Starter is back in, wired and tested. Steering is back in place too. I'm about half way thru plumbing the oil cooler. Plumbing at the grill end, will be interesting. Rad and fan are still out, as I'm still working on the oil cooler. Plug wires will have to be updated. Looks like my 135 deg ends won't work to well with the headers. Drivers side looks like 180s will work nicely, but the pass side, front two, cyls 2 and 4, will probably need 90s. 6 and 8 will probably work with 180s. Tranny lines are still off. Tranny filler tube is still out too.
A preliminary mock up of the X pipe, looks like she'll have to make a trip to the muffler shop. This aint gona be a bolt on.
-Mark
2024 Equinox LT AWD
2015 Yamaha FRJ
2024 Equinox LT AWD
2015 Yamaha FRJ
- Basement Paul
- Posts: 3538
- Joined: Sun Jul 17, 2005 9:27 pm
- Location: In the dirt.
Re: Headers
We'll see what your attitude about them is after you make your first good passmarkss327 wrote:Headers for this car, still suck.![]()

[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]
-BP[/quote]
BP- Feel free to PM me, call, email.... with your muffler guy. I last used the muffler shop across from Classic Chevy on Center st, with 'OK' results. He did the Dyno Max on the Avalanche.
I'm one step closer on the oil cooler. It's plumed. I'm not real happy with the line routing, and a re-do is inevitable, but for now, It's the best I can come up with. Mid summer I'll probably have some sort of revelation, and it'll hit me as to how to do it better....
Next up:
Tranny lines
Rad, fan, belt, hoses, coolant etc.
Plug wires
I'm thinking an 'open header' video is in order...
Mostmint, man, this thing (now with headers) had better do 12.90s 'out of the box'.... Although, maybe my 600cfm Edelbrock may now need upgrading....
I'm one step closer on the oil cooler. It's plumed. I'm not real happy with the line routing, and a re-do is inevitable, but for now, It's the best I can come up with. Mid summer I'll probably have some sort of revelation, and it'll hit me as to how to do it better....
Next up:
Tranny lines
Rad, fan, belt, hoses, coolant etc.
Plug wires
I'm thinking an 'open header' video is in order...

Mostmint, man, this thing (now with headers) had better do 12.90s 'out of the box'.... Although, maybe my 600cfm Edelbrock may now need upgrading....
-Mark
2024 Equinox LT AWD
2015 Yamaha FRJ
2024 Equinox LT AWD
2015 Yamaha FRJ
Open header Video
-Mark
2024 Equinox LT AWD
2015 Yamaha FRJ
2024 Equinox LT AWD
2015 Yamaha FRJ
- ttamrettus
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- TireSmoker
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- Basement Paul
- Posts: 3538
- Joined: Sun Jul 17, 2005 9:27 pm
- Location: In the dirt.