Headers for BN4/early 3000

[57_100_6]

What type of mods are required to instal headers on a BN4 or early 3000?
I have changed over to triple Weber's and since I need to replace the exhaust and intake gasket I would also like to install headers at this time. All the headers I have found fit the BJ8 but have heard that they will fit the early cars if the outrigger is cut.
Can I use the stock silencer and pipes or is it better to go all the way back with 2' bore?
Anyone with experience or pictures?
Thanks

 

[Randy Forbes]

I'm using an off the shelf Monza exhaust connected to the headers.

During the car's restoration period, I substituted a BJ8 L/F outrigger, but if your existing one is in good shape, it can be easily modified for the same results (cutting/welding reqd.).

I strongly recommend that you have a thermal barrier applied to the headers before final installation; DO TEST FIT them first, prior to shipping them out for coating, in case there are clearance issues to correct.

More pictures at: https://www.rfdm.com/gallery/album44 Main album has several embedded albums, so don't miss those...

 

[57_100_6]

Thanks Randy,
That is the exact info I need to proceed.
Thanks again.

 

[GregW]

What is your goal with the engine? Have you changed cams?

 

[TimK]

Randy, I went to your site and after going through some of your Healey photos, I happened on the 362 photo album of your installation of a supercharger on your BMW. Healey's are child's play compared to the mechanical genius you displayed in those photos of dealing with the complexities of that installation. I'm also amazed how much you accomplished while taking all those photos.

 

[Randy Forbes]

Hi Tim K,

I've done the supercharger installation several times, but generally only once per car, unless the car requires additional work later on, like pulling the head to replace the head-gasket.

People send me their BMW M Coupes/Rdstrs from all over the country, and I work on them in my home garage, so if you're thinking that I'm always having to work on my own car, well it's not that unreliable :wink: There are probably fifty or more (>50) customer cars in that photo gallery (I know there are more than 12,000 pictures total, so keep that in mind should you suffer from insomnia).

I've been told in some cases, it was because I post a picture album of every car I'm working on, that they decided to give me their business in the first place. Most of the owners are VERY FUSSY about who touches their baby, and this way they can track progress and have some insight on when to make plans to collect their car.

Today's problem is trying to figure out why these new (supercharger-grind) cams I just installed aren't acting right...

 

[TimK]

This is what I appreciate most, getting to know a little more about the people who are on this forum.

 

[57_100_6]

Greg,
Rebuilt engine in 2000 with Weber's in back of mind. Used 3000 pistons and rods bored .040. Converted to the 6-port head. Cam is Kastner A-6 grind 255` duration @ .050 with .275 lobe lift. Advertised is 306`. Right now I am running stock exhaust and since I have a leak and need to replace the exhaust and intake gasket I thought I would open the exhaust with headers.

 

[GregW]

Today's problem is trying to figure out why these new (supercharger-grind) cams I just installed aren't acting right...

Too much overlap?

 

[GregW]

Greg,
Rebuilt engine in 2000 with Weber's in back of mind. Used 3000 pistons and rods bored .040. Converted to the 6-port head. Cam is Kastner A-6 grind 255` duration @ .050 with .275 lobe lift. Advertised is 306`. Right now I am running stock exhaust and since I have a leak and need to replace the exhaust and intake gasket I thought I would open the exhaust with headers.

It <span style="font-style: italic">would</span> be tough putting triple Weber's on a galley head :wink:. It sounds like you've laid the ground work for a nice engine. Putting Weber's and headers on a stock unit is kinda a waste of money IMHO. To answer one of your questions, I'd recommend the 2" exhaust over the stock diameter.

 

[57_100_6]

Thanks Greg,
I will stick with 2' all the way out and follow Randys excellent example.