2008 XLR-V Manifold replacement

[smittyman33]

Question for you all. Iam in need of a new cat, thus needing to replace manifold I assume. Are the magnaflow OEM ones a good fit? Huge job to change so best to do both at same time? Also, seems like the Corsa 14156 exhaust is the best for car, will it bolt up to the magnaflow namifold easily?

 

[David_B]

Question for you all. Iam in need of a new cat, thus needing to replace manifold I assume. Are the magnaflow OEM ones a good fit? Huge job to change so best to do both at same time? Also, seems like the Corsa 14156 exhaust is the best for car, will it bolt up to the magnaflow namifold easily?

Stick with the stock manifold. Magnaflow has terrible customer service, and they don't have a CLUE about what they sell for the XLR. It's hard to get the manifold off, but not impossible. The manifolds I got from them came with bolts that wouldn't even go through the holes in the manifold, let alone fit the head bolt holes. All they have told me is to return them (after spending months with them telling me it fits, and if it doesn't something is wrong with my car) or pay MORE money to have them modified to fit (which they pretty much suggested from the start, which tells me they 100% know they don't fit some XLRs).

Some people have had just Cats welded to the stock manifold. Some have had the CATS gutted and the ECM flashed to ignore the back sensors (illegal for road use). Some just have the manifold replaced without taking the engine out, which is hard, but not impossible (at least on the NA engine).The passenger side is hard to get off, and I bet that's the one giving you problems?

If it's just the passenger side, get the stock manifold.

I have no idea how hard this is on a V. Might be harder. Can't be easier.

 

[FulviXLR]

Stick with the stock manifold. Magnaflow has terrible customer service, and they don't have a CLUE about what they sell for the XLR. It's hard to get the manifold off, but not impossible. The manifolds I got from them came with bolts that wouldn't even go through the holes in the manifold, let alone fit the head bolt holes. All they have told me is to return them (after spending months with them telling me it fits, and if it doesn't something is wrong with my car) or pay MORE money to have them modified to fit (which they pretty much suggested from the start, which tells me they 100% know they don't fit some XLRs).

Some people have had just Cats welded to the stock manifold. Some have had the CATS gutted and the ECM flashed to ignore the back sensors (illegal for road use). Some just have the manifold replaced without taking the engine out, which is hard, but not impossible (at least on the NA engine).The passenger side is hard to get off, and I bet that's the one giving you problems?

If it's just the passenger side, get the stock manifold.

I have no idea how hard this is on a V. Might be harder. Can't be easier.

Sent from my iPhone using Tapatalk

 

[David_B]

Here's a couple pictures showing how far off the fit is.

 

[smittyman33]

Magnaflow's installed

finally got my magnaflow manifolds and corsa exhaust installed and it is magnificent. Looks and sounds just like I thought it would. Manifolds fit perfectly on my installation, although very tight to work in there. Exhaust bolted up quickly and was off to the races. Perfect combo of nice highway rumble and the loud sound of power when you fell the need to let it fly.

 

[David_B]

I was pretty sure they would fit late 2006 and after. The right manifolds are different part numbers from 2006 on from GM.

Now you need a CAI. Somewhere there's a post someone said they got +35hp with that combo on a dyno.

 

[XLRobbie-V]

I was pretty sure they would fit late 2006 and after. The right manifolds are different part numbers from 2006 on from GM.

Now you need a CAI. Somewhere there's a post someone said they got +35hp with that combo on a dyno.

Dave, 2 questions:

1) I have a 2006 -V, how do I tell if it's a late model 2006? Is there a point where the manifolds would NOT fit a 2006 -V?

2) What is "Now you need a CAI"?

Thanks

 

[David_B]

If it's a V it has the newer manifold. I'm pretty sure the fact they list the old one as 2006 also is for the non-Vs.
CAI Cold Air Induction.

 

[XLRobbie-V]

If it's a V it has the newer manifold. I'm pretty sure the fact they list the old one as 2006 also is for the non-Vs.
CAI Cold Air Induction.

Okay David, thanks for the clarification.