Header patterns

Post by **demo2** » Sun Feb 26, 2012 1:06 pm

Hi people, am i right in saying in a 4-2-1 system, on the passenger side i join 1 and 5 and 3 and 7? on the drivers side i have joined 2 and 4, 6 and 8. I have seen pics of passenger headers that have 1 and 3 joined together and 5 and 7 but seem to remember because of the firing order passenger side should be 1 and 5 , 3 and 7. Just wanna be sure before i start passenger header.

Post by **demo2** » Mon Feb 27, 2012 10:40 am

Anyone ??

Pitschi · Post by **Pitschi** » Mon Feb 27, 2012 10:59 am

Scroll down and the next site too:

http://www.the289register.com/phpBB3/vi ... &start=105

kiwicar · Post by **kiwicar** » Mon Feb 27, 2012 11:44 am

Hi
If you are making a 4-2-1 system then you want to avoid joining in the first instance 2 cylinders firing 90 degrees apart, with a firing order of 1-8-4-3-6-5-7-2 the ones you want to avoid joining as pairs (that are physically probable) are 8&4 and 5&7. so on the odd numbered bank joining the middle pair and the outer pair are the best bet (1&7, 3&5) and on the even bank this will work (2&8, 4&6) but also (as it is easier to make) then 2&4 and 6&8 will are a better bet.
Avoid 1&3, 5&7 as pairs.
Hope this helps
Best regards
Mike

Post by **demo2** » Mon Feb 27, 2012 10:33 pm

Cheers for that, i thought i'd heard somewhere about the odd numbered bank being 1&5 3&7. Can crack on now.

kiwicar · Post by **kiwicar** » Tue Feb 28, 2012 10:11 am

Hi
1&5 3&7 would also work (firing 270 degrees apart), but a pig to make and fit in the space, 1&7 3&5 has 180 degree spacing, works ok and is a great deal easier to make and fit in the bay.
Best regards
Mike

Post by **demo2** » Tue Feb 28, 2012 10:19 am

I like a challenge