Is it possible to convert a long 4:1 collector to a 4:2:1?

[CageyH]

If so, how?

Or would it be cheaper to buy a new 4:2:1?

I would need a 2.5" collector to suir a Raceco can.

[Myles]

It would be possible - you might need to shorten the primaries in order to provide enough space for the collector, secondaries and can though.

 

Simpler and better to sell your existing system and buy a 'proper' 4:2:1

 

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Alcester Racing 7's Equipe - 🙆🏻™

 

Alcester-Racing-Sevens.com

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[CageyH]

So, where could I get a 4:2:1 made to have a 2.5" exit from the collector, and how much is it likely to cost?

What sizeprimaries would be best suited to a VHPD K seies? I am hoping to have about 200 BHP this winter, with more next winter, when I drop on a modified head...

[tiddy1]

you have to very careful as you have to connect the correct twopipes together, 4 and 1 must be paired with 2 and 3

 

Simon

[PAUL MARRIOTT]

EBD - Tingewick nr Buckingham

[Sootysevener]

Cagey

 

Anythings possible but as stated to create the 4-2 you would need to shorten at least one of the pair of primaries ( bad move for the sake of both gas flow speed and balance between the pairs) and/or reconfigure the sweep bends in the promaries which would probably mean recutting the sideskin. This would then still leave some further fabrication to create the 2-1 collector.

 

You will allegedly get better performance out of a 421 set up but to ba$tardise your existingtube/collectors will almost certainly compromise any gains in mid range torque.

 

I'd think seriously about replacing the system with a 421 designed as such - you can always sell the existing pipework to someone who is looking for top end performance to offset the cost.

 

Strongly supportive of Powerspeed - speak to David Parris

 

phone no. 01233 662225

fax no. 01233 620889

 

Best of luck

 

 

 

 

David

 

1989 1700XF SS clams with carbon

webshots here

[EFA]

You don't need to shorten the primaries. I run 32" primaries and 16" secondaries.

 

K2RUM - The car of two halveswith a hole in the engine

[Paul Deslandes]

Arnie, how long is your silencer and how effective is it? As I recall from an earlier piece on this subject, your manifold is formed so that the bottom bend as fairly far forward, allowing a reasonable length of silencer in the space up to the front of the rear wing. Any pictures?

 

Paul