Swapping Headers Without Dropping Engine

[racknid]

Last weekend I exchanged beer for my neighbor's help and we swapped out my OEM exhaust with a Billy Boat Fusion system.

That all went fine and happy with the results.

We also took a look at swapping my OEM headers for the MagnaFlow units I purchased a while back.

My neighbor has extensive experience and great collection of automotive tools, but after messing with the passenger side heat shield for 45 minutes, he cried uncle and we settled for just getting the exhaust done. Even if we tried to work around the loose heat shield without fully removing it, he just couldn't see a way to get at all the header bolts without dropping the engine.

I see several threads where V owners mention getting their headers removed with the engine in place. Anyone who has done it have any tips for us to make another pass at it?

He has an engine hoist if we have to go that route, but would much rather do it the "easier" way if at all possible.

Thanks.

 

[richardyoo]

I installed D3 headers on my V myself. On the ground, with jackstands, and only hand tools - with no prior experience. I found the driver side significantly easier than the passenger side - the AC lines and such made the passenger side much more challenging.

I did not have to move the engine in any way to get it out... but I do remember it being difficult. I ended up driving around with only the driver side installed for a few weeks before I could get back to trying to figure out the passenger side.

Getting the old manifolds out was more difficult than installing the headers - the D3 headers had much more room than the OEM manifolds did.

I actually did this process twice... the first time was just installing them... and then a year or two later I removed them to apply heat wrap and decided it was easier to do with them off the car than try to do it with them installed. And I ended up installing stage8 locking fasteners the 2nd time around.

I don't have any advice for you but take the time and have some patience. There was nothing special I did - but I remember it taking most of the day to do the passenger side removal and install.

 

[racknid]

I installed D3 headers on my V myself. On the ground, with jackstands, and only hand tools - with no prior experience. I found the driver side significantly easier than the passenger side - the AC lines and such made the passenger side much more challenging.

I did not have to move the engine in any way to get it out... but I do remember it being difficult. I ended up driving around with only the driver side installed for a few weeks before I could get back to trying to figure out the passenger side.

Getting the old manifolds out was more difficult than installing the headers - the D3 headers had much more room than the OEM manifolds did.

I actually did this process twice... the first time was just installing them... and then a year or two later I removed them to apply heat wrap and decided it was easier to do with them off the car than try to do it with them installed. And I ended up installing stage8 locking fasteners the 2nd time around.

I don't have any advice for you but take the time and have some patience. There was nothing special I did - but I remember it taking most of the day to do the passenger side removal and install.

Thanks for reply Richard.

Do you remember if you were able to remove the heat shield on the passenger side or did you just work around it? There didn't seem any way to get it pulled clear from the bottom without doing some significant damage to it in the process.

 

[richardyoo]

Do you remember if you were able to remove the heat shield on the passenger side or did you just work around it?

Its been about 10 years since I did the work so I don't remember exactly... its entirely possible I did it the way you suggested - where I just unbolted it, but let it float there until I could get the entire manifold assembly out. My heat shields are not damaged.

 

[David_B]

That's what I did. Remove the heat shield bolts, move the heat shield around to get to all the header bolts, once the manifold was loose wiggle the heat shield out.

You have to take out the dipstick, be sure you put it and the heatshield back in loose before putting the bolts in the manifold, I forgot the dipstick and had to take all the bolts out again

Also it can be a little hard to figure out what's going on with the O2 sensor connectors if you decide to take them out with them on the manifold. The connector is protected by a foil wrap that uses foil tape to close up. You can get replacement tape at any auto shop in the Muffler section, it's meant for temporary hole fixes.

The bolts on the passenger side are a major pain to get off the stock manifold. If I had to do it again I think I'd look at what attaches the A/C lines and the fuse box and at least loosen the mounts to move them out of the way even a little bit.

The other problems I had with my failed install of the Magnaflow manifolds on my 2004 where the difference between the 2004 and 2006-V/2007-09 passenger manifold. Magnaflow made multiple versions of these over the years and decided to stop making the one that fits the 2004/5. They won't admit they know what they sell now doesn't fit the passenger side on 04/05 and many non-v 06's. I tried to get them to work with me but they were not interested. The first thing out of support's mouth was "you can have them modified at a muffler shop".

I suppose you could put everything on loose then crank all the bolts down and put your entire exhaust under a lot of torque waiting for the heat to bend all the parts to fit, maybe. I was not comfortable doing that on an aluminum head.

I have no faith in Magnaflow, they shipped one manifold with the complete wrong donut gasket, and both came with the completely wrong size bolts. Bolts they said they didn't provide, then they said "GM must have changed the size later", THEN I actually tried to test fit the bolts through the holes in the manifold and they where too big in diameter to even fit through the holes in the manifold! LOL

I'm just going to stick to the stock GM manifolds..

As Richard said, take your time, stripping the head of one of those bolts would probably force you to have to remove the engine, there's not a lot of space on the passenger's side.

Its been about 10 years since I did the work so I don't remember exactly... its entirely possible I did it the way you suggested - where I just unbolted it, but let it float there until I could get the entire manifold assembly out. My heat shields are not damaged.