I'm just wondering if you can get bigport manifolds for 3k that all big all the way threw the inlet manifold?

We have a few here but they start of big then slowly shrink down there the normal size???

 

Cheeers

That's a negatory!

That's a negatory!

ahhhhhhhhhhhhkk

Pongwong I will cover your options.

 

From what I know there are basicly 4 different OME inlet manafolds for a 3/4 k that support single carby. Bigport (30mm) with bent runners. ( runners srink in size in between head and plennum Bigport (30mm) with straight runners. ( runners stay consistant in size and feed 2 to 1 then 2 to plennum) Mid port (27mm) with bent runners. (runners stay consistant in size and feed 4 to 1 ) Small port (25mm) with bents runners. (stock) The bigport with straight runner has other issues, It's plennum area is small you could hog this out, and it does not support a dual exhaust manfold so any HP gains in the inlet will be lost in the exhaust, you could get around the exhaust issue with extractors, For speedway Juniors sedans and I suspect you race in the class by the questions you ask, we must run the stock exhaust manafold.

 

Here's some pix to tell the story.

 

Common small port was we all know and love.

 

 

Midport I suspect these are on 4k and later but now sure.

 

 

Common bigport (Note If anyone has a spare one of these please PM me as this one is cracked and I would like to buy one)

 

 

Early biport I think.

 

 

Bigport straight plenem area.

 

 

Bigport straight runner sizes.

 

 

Bigport straight note exhaust triangle is 180 deg out.

 

 

Bigport straight exhaust manafold.

 

 

Hope this helps

Cheers

Andy

Edited September 15, 201016 yr by Andy43

that's worth a rep point!

woow man cheers heaps u legend

wow that's good faq-worthy info!