Conversions & Hybrids - Question: Hacking stock 98-02 manifold

I have two questions below - but a little inside info before you answer...

I am swapping '01 LS1/T56 into my '68 Chevy stepside C-10 truck. I had been told by some people the stock WS6 headers wouldn't fit, but I found the manifold and cat slip right in, no problem! More info on that:

http://www.ls1tech.com/forums/showpost.php?p=4322375&postcount=71

Anyway, long story short here is my problem. See the little flange that sticks out of the heat shield on the passenger side manifold?

http://satellitehead.com/uploads/ls1headers001.jpg

Well, I need to grind it down to clear the engine mount and frame, but I have tow questions:

1) What the heck is it for? Looks like it was designed to be tapped for something?

2) IS it safe to grind, and if yes, how much can be safely ground down? I'm assuming it's hollow on the other side.

Thanks!

ttt

Thanks again.

I have some 98 manifolds that I just pulled off (camaro). They don't have that tab. I've heard that they're a bit more restrictive, but I don't know for sure. I'll post a pic if ya like? I'd sell them for cheap!!! if you want 'em!

Just looked on my car, (02 camaro) and it dosent look like anything goes to them. The tab is just there, lol.

Not sure about that. I haven't noticed those on my '01, but I haven't looked real closely either. About being told they wouldn't fit, I was told the same thing about using the manifolds in my '69, so I dished out $500 for S&P headers, then I find out later that the factory manifolds would have fit :bang:

Anyone know how far down I can safely grind that thing? I am amazed how cleanly and nicely these fit into my truck. Plan on posting a huge "HowTo" thread once this is all done. Any advice anyone gives RE: header modifications is going into it for the entire community to benefit from.

Glad to hear I'm not the only one that had this problem :)

I say be a pioneer and hit it with the grinder!

I've got my Dewalt 4½" ready to go at it. I'll give it another hour or two before hacking away :D

Hell, if I can get the hydraulics in today, all I'll really have left is figuring out the gas pedal setup :D

Ok, the '01-'02 is a no-go on the passenger side. In addition to that little jut-out being in the way, I notice the flange is rubbing the frame as well when bolted all the way down. I'm just gonna contact ashape about his I guess. Hopefully I'm not aimlessly dropping cash on something that doesn't work.

Not sure what the heat shield on the outside of this guy is good for :\

Anyways, some pics for reference - will be removed eventually, so if this is of interest you, right click and "save as" :)

Before grinding:
http://satellitehead.com/uploads/ls1headers2001.jpg

After grinding:
http://satellitehead.com/uploads/ls1headers2002.jpg
http://satellitehead.com/uploads/ls1headers2003.jpg
http://satellitehead.com/uploads/ls1headers2004.jpg

Fitment post-grind (note the heat shield touches):
http://satellitehead.com/uploads/ls1headers2005.jpg

Flange touches framerail when bolted in:
http://satellitehead.com/uploads/ls1headers2006.jpg

Full overhead view w/dipstick inserted - Tight fit when using the truck oil dipstick (I converted to a truck pan/pickup/tube for xmember clearance):
http://satellitehead.com/uploads/ls1headers2007.jpg
http://satellitehead.com/uploads/ls1headers2008.jpg

I hope this might help someone in the future? :)

On the 2000 Camaro, it is for part of the air injection system. Mine has been removed, and the hole filled up.

Anyway, long story short here is my problem. See the little flange that sticks out of the heat shield on the passenger side manifold?

http://satellitehead.com/uploads/ls1headers001.jpg

Well, I need to grind it down to clear the engine mount and frame, but I have tow questions:

1) What the heck is it for? Looks like it was designed to be tapped for something?

2) IS it safe to grind, and if yes, how much can be safely ground down? I'm assuming it's hollow on the other side.

Thanks!
On the truck manifolds that is where the EGR USED to get it's exhaust gasses, but I see you already have a flange and hole for EGR. When GM stopped using EGR, they simply stopped drilling the hole out. Eventually they changed the casting molds to eliminate the lump. Some heat sheilds still have the open space for the lump even though it's long gone.
I have no idea how much of it you can cut off before poking a hole in the manifold.
Ken

I just wanna say thanks again to everyone who's repsonded in this thread.

How bad do you think it would it be if I removed the heat shield on the manifolds? What kind of problems will it cause with surrounding components like plug wires, engine mounts, etc? I'm assuming GM put the heat shields on them for a reason. Was it something as stupid as just keeping people from touching the things, or more in depth than that?

On the 2000 Camaro, it is for part of the air injection system. Mine has been removed, and the hole filled up.

Did you simply torch/plasma/cut it out and weld a cap over it? Just curious.

How bad do you think it would it be if I removed the heat shield on the manifolds? What kind of problems will it cause with surrounding components like plug wires, engine mounts, etc? I'm assuming GM put the heat shields on them for a reason. Was it something as stupid as just keeping people from touching the things, or more in depth than that?

If you're doing the usual performance stuff like free flowing exhaust and lower thermostat temperature, I don't see any problems with removing the heat shields. Your truck probably has more air moving through and around the engine compartment then newer cars and trucks. You could always grind or sand the manifolds smooth and have them ceramic coated. That would look good and still offer some heat containment.
Ken

Looks to me like you have enough room. You could take a cutoff wheel and take some metal off of the lower flange without impacting the strength. I agree with Ken on removing the heat shields, then clean them up and ceramic coat them. Also what is that piece on the frame the you are touching with the upper manifold? Could that be notched to give you a little more clearance?

Pat

Also what is that piece on the frame the you are touching with the upper manifold? Could that be notched to give you a little more clearance?

Upper part of the manif is touching the engine mount (you're talking about that part of the frame under the front two cylinders with the bolts atop the framerail, right?). The flange where the manif meets the cat is just frame. I could grind down the header and flange to compensate, I think. Still waiting on ashade98 to get back in touch with me re: '98 manifs :)

I looked at my friend's 2000 Camaro SS last night to see the hydraulic actuator location and the passenger side header. He has the same flange on his header, but it's being used, looks like by the AIR/EGR setup. Very interesting. So, for the record, it's used in the 2000 modem Camaro if nothing else.

I'd honestly prefer to plasma this section out, sand, refinish and JetHot coat them, but I mean ... at that cost, may as well buy new ones, right? :D

That tab is probably there for the GM Sound tech engineers... They add some funky shit to get just the right sound. Thats why most air intakes have weird contraptions on them.

-matt

Man I love that Chevelle.

Good news. The stock '98 manifolds fit like they were meant for my truck. Thanks ashade98 for the quick, cheap sale.

Pics and more info here:

http://www.ls1tech.com/forums/showpost.php?p=4395473&postcount=80

Thanks to all who contributed with this thread.