Valve covers don't clear Bursch headers

JohnJL · 10-23-2006, 05:24 AM

Anyone else find they can't remove their lower valve covers when Bursch headers are installed? There is clearance between the collector and the cover, except not enough to slip the valve cover off the studs!

My exhaust is all installed and welded up so I really don't want to have to drop the entire exhaust to check the valve clearances...

Anyone else have this problem with a 3.0 Carrera and the Bursch headers our sponsors sell? I didn't know this was a problem!

John Brandt · 10-23-2006, 07:35 AM

It's tight, but they should go out. you have to angle it up, then out

JP911 · JP911's Garage

You may need to grind some material off the valve covers and/or shorten the studs a bit. I ran into this issue with 993 heat exchagers on my motor and ended up cutting away a small part of the exchanger that the heater hose connects to. I also had to do a small amount of grinding on the valve covers.

ckissick · 10-23-2006, 07:42 AM

I have the same problem. Bursch headers on a 1978 3.0. But only on the passenger side. Whenever I need to remove the valve cover, I loosen the header enough to move it out of the way. And, of course, I detach the muffler from the one header, also. I still have the stock valve cover. It doesn't leak, so why update?

I'm surprised to hear that I'm not the only one. Maybe Bursch should work on that.

ckissick · 10-23-2006, 07:45 AM

I just read JP911's post. The blockage on mine is too big for any grinding to help. It doesn't look like I can shorten the studs enough to help, either. I guess some are worse than others.

911pcars · 10-23-2006, 10:25 AM

Ever wonder about the close proximity of 400º+ temps from the exhaust system?

Small pic, but the Thermax temp. strip reads almost 300ºF + after normal driving.

Sherwood

JohnJL · 10-24-2006, 01:56 AM

Prolly why lots of racecars leak like a sieve from the covers....3-400 deg isnt good for gaskets...

tsuter · 10-24-2006, 04:17 AM

I have a clearance problem on the lower stud closest to the front on driver side when removing the lower cover.
I just remove the nut and stud, then the cover comes off.
Back on is the same. Cover first, then the last stud and nut.

Joe Bob · Joe Bob's Garage

Common problem with turbo style valve covers....grind the offending parts off.....

I had to do a partial engine drop on my 914/6 when the PO failed to remember to do so.

JohnJL · 01-27-2007, 03:39 AM

Just to close the story...spent 2 hours today sawing off the end of the 2nd stud from the front on the right-hand side. Then another hour with a dremel to grind the material off the cover. Maybe dropping the headers off would have been faster this time but now they're ground down and come on/off properly.

2nd day of tuning is up tomorrow...a few valves were a little tight and 2 were a little loose, but now the covers are drilled for the 2nd plugs.

ckissick · 01-27-2007, 07:31 AM

I tried your solution with mine, but soon realized I'd have to grind too much. I just loosen and lower the headers when I adjust the valves. Not a big deal. For one thing, without the heat exchangers, its easy to reach all the nuts.

PatrickB · PatrickB's Garage

Quote:

Originally Posted by 911pcars

Ever wonder about the close proximity of 400º+ temps from the exhaust system?

Small pic, but the Thermax temp. strip reads almost 300ºF + after normal driving.

Sherwood

Would Heat Sheet Exhaust Heat Barrier's that our host sells help? Just curious, as I was considering the pro's & con's of putting Bursch Header's on my 3.2...

http://www.pelicanparts.com/catalog/shopcart/911E/POR_911E_EXHpip_pg3.htm

Joe Bob · Joe Bob's Garage

Ya gotta grind some of the fins off....BTDT.

PatrickB · PatrickB's Garage

Off of the valve cover?

Joe Bob · Joe Bob's Garage

Yup....

PatrickB · PatrickB's Garage

Thanx Mike!

I was also curious if it was a good idea to put them on if Bursch Headers generate more heat than the stock exhaust?

Joe Bob · Joe Bob's Garage

They make a heat shield that bolts to the valve cover. I think it's called HEET Shield.

The 914/6 has the same problem with the turbo valve covers.....

911pcars · 10-18-2007, 07:03 PM

Quote:

Originally Posted by PatrickB

Would Heat Sheet Exhaust Heat Barrier's that our host sells help? Just curious, as I was considering the pro's & con's of putting Bursch Header's on my 3.2...

http://www.pelicanparts.com/catalog/shopcart/911E/POR_911E_EXHpip_pg3.htm

The Bursch headers I've seen position and orient the muffler flange adjacent to the valve cover. In fact, more than adjacent. It's so close, there isn't room to install HeetSheets which normally stick out from the valve cover face approx. 1" (24mm). I never understood the reason why there couldn't be more separation between engine and exhaust pipe, especially when the pipe radiates 300º+ temperatures. Even rotating the flange 90º relative to the pipe would provide more clearance in this area.

As Mikez says, on a 914-6, the fit is so tight between engine and chassis, the fins from a turbo valve cover must be ground down for adequate installation clearance. Customer feedback suggests HeetSheets can be installed in 914 > 914-6 conversions but not factory 914-6s due to the chassis interference issue. No install issues with 911s/964s with factory or SSI heat exchangers.

Sherwood
www.seinesystems.com

PatrickB · PatrickB's Garage

Thanks Sherwood~

I'll take that as a "NO" they won't fit a 3.2 with Bursch Headers? Options~ I could either grind on the stock 3.2 valve covers, or perhaps cut/re-weld the flange orientation on the header to be more valve cover/HeetSheets friendly??

JP911 · JP911's Garage

Another option to the HEET sheets would be the header wrap (kind of like thick ace bandages) that some racers use.