Jump to content

4-1 V8 headers


Recommended Posts

I've started with building two 4-1 headers.

 

As far I have seen on the market, there is nothing available for racing purpose so I need to do it myself.

Tubes are already bought, tig welder and gas is ready to go.

 

I've never done such a thing before.

Will be interesting to work on this.

 

I'll start with building the collector.

 

Cheers

Chris

Link to post
Share on other sites

Good luck Chris

Having seen the high regard for you on the forum Im sure you can do a great job.

You must share some before - during - and after picture.

 

Happy hobby Christmas

 

H

Link to post
Share on other sites

Hi Chris,

 

Mick Richards and Peter Burgess might be able to offer some useful suggestions re headers, from their past experimentations in the days when Mick's V8 was a quick as it got and won successive Championships.. . . .

 

I'll try and organise photos of the headers on the Drag Car next week (it's currently all wrapped up for the winter period), they seem to work pretty well and exit via a single drainpipe on the left hand under the door . . . . . I know that when Paul built the engine he tried several systems, until the car's rwhp exceeded the capacity of the rolling road.

 

Cheers,

 

Alec

Link to post
Share on other sites

Hi Chris. Popular wisdom has it that a 4-2-1 system is favoured for V8s with a 90 deg crank. The 4-1 type is associated with a flat plane crank.

 

Assuming a 4-2-1...

And a 18436572 firing order...

And a 90 deg crank...

The left bank should pair cylinders 1-5 and 3-7.

The right bank should pair cylinders 2-4 and 6-8.

Opinion is divided on the need for a balance tube.

 

Tons of stuff on the net. Get searching.

 

Are you making merge collectors?

 

Link to post
Share on other sites

Hi Spyder,

 

from what I see on the web, Euope seems to favorise the 4-2-1 stye, America seems to prefer the 4-1 style. Especially for full out engines.

 

I tend to make the merge collector by myself.

Link to post
Share on other sites

Interesting post, as I'll have to make myself a pair of exhaust manifolds for Rivet, now with a 3L5 Rover V8. Not for racing purpose, but the space Under the alloy bonnet is strictly limited !

Link to post
Share on other sites

Is it worth looking at MGRV8 system - a factory made car with a tubular exhaust manifold?

That was 4-1 each bank and brought the two banks together in the silencers - so it was balanced. Then exit in two pipes.

 

https://www.mgocspares.co.uk/acatalog/MG_RV8.html

https://www.ukmgparts.com/catalogue/rv8-midcat-14-sub67rv8-exhaust-system-and-mountings

 

Peter W

Edited by BlueTR3A-5EKT
Link to post
Share on other sites

The TR8 has a steering shaft in its way.

From what I see on the MG parts pictures it won't fit.

 

Exhaust headers are a very power sensitive items.

On my TR4 I had one top header and a few flop headers.

Edited by MadMarx
Link to post
Share on other sites

If you need to wrap your new manifolds with heat protector, search for refractories owen accessoiries : it has been one of my jobs when younger, and the rolls are 10 time cheaper that he ones sold by racing cars specialists....

Link to post
Share on other sites

I never use wraps on headers.

Wraps soak power.

I removed the wraps from the headers on the photos and just left a 2" length to protect the ignition cables.

 

But thank you for the very good advice to look out for oven stuff.

Edited by MadMarx
Link to post
Share on other sites

You're welcome

 

I never use it neither, not because it soak power -did it ?- but because I'm not sure that it is of some use on a road car.

Link to post
Share on other sites

Looking good.

Its a complicated plumbing job looking at the pictures above posts.

 

Youll have it done by next year.

 

???? Doh !!!!!

Link to post
Share on other sites

I've not used this, never made my own exhaust system, but being able to model it in adjustable plastic before producing it in steel sounds a good idea:

 

https://horsepowersports.com/icengineworks-exhaust-header-modeling-blocks-make-custom-headers-like-a-pro/

 

John

post-535-0-81657600-1514716097_thumb.jpg

post-535-0-20464000-1514716109_thumb.jpg

Link to post
Share on other sites

Good luck!

Unfortunately I never had the chance to make a good header.

I had to find my way besides the steering and besides the starter

and at the end wanted to fit both headers with engine in the car.

 

I tried a lot with the connector between left and right header.

Definitely got power increase in the midrange with the connector

about 110 cm away from cylinder head. Again there must be a place

to be found for the connector tube without resulting below the TR6 frame.

 

post-13092-0-45049200-1514905028_thumb.jpg

Link to post
Share on other sites

I've not used this, never made my own exhaust system, but being able to model it in adjustable plastic before producing it in steel sounds a good idea:

 

https://horsepowersports.com/icengineworks-exhaust-header-modeling-blocks-make-custom-headers-like-a-pro/

 

John

I use instead water plastic plumbing tube. They cost € cent and you can cut them and there are angled connectors.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.