6 branch manifold sizes help

[Mk3highline 287]

Hello

I've picked up a 6branch for a vr6 but the diameter of the whole thing seems bit big

Anyone got one off the car that can measure the tube sizes pls?

I will once I find my vernier

[Bealieboy 1,625]

I'll check mine out for you when I get home

[Mk3highline 287]

It looks like it's a supersprint copy

[Bealieboy 1,625]

Same as mine by the looks of it. I'll measure up now

[Bealieboy 1,625]

353mm across manifold by 90mm depth at the mounting

63mm at downpipe

44mm branch pipes

50mm intermediate pipes

Approx 710mm total length from manifold to downpipe flange.

Hope that helps.

[Mk3highline 287]

Thank you one I've got is same size

Seems like a bit on the big side I think

Will have to get the calculator pen and paper out now

First rough calculations we need for them tuned to 5500rpm

Your Primary Tube Length is 38.85

Your Primary Tube Diameter is 1.26 inches

Your Collector Diameter is 2.48 inches Two Collectors

Online calculator but need to get exact cam profile specs

This is going to be fun

I think I had some software somewhere need to see if I can dig that out

Edited May 30, 2015 by Mk3highline

[Mk3highline 287]

Well got these off vortex engine codes are different but big one is the r32 and small ones are the 2.8

Port Sizes and Approx Areas

Intake Long

BDF 39.44mm high, 35.50mm wide - approx 1400.12 sqmm port area

BJS 41.25mm high, 35.55mm wide - approx 1457.3625 sqmm port area

BJS port is raised more in the casting.

BJS port area gain is about 4%

Intake Short

BDF 31.01mm high, 41.07mm wide - approx 1271 sqmm port area

BJS 38.59mm high, 38.52mm wide - approx 1486.4868 sqmm port area

Comparing the short and long ports the BDF areas are more dissimilar.

BJS gain in port area is about 16.95%

Exhaust Ports

All exhaust ports on both heads share dimensions between them

BDF 33.80mm high, 29.06mm wide - approx 980.2 sqmm port area

BJS 34.00mm high, 33.06mm wide - approx 1122 sqmm port area

BJS port area gain is roughly 14.5%

These manifolds for the 12v have a internal diamete of 43mm so the area is 1452.2 mm squared (pie times radius squared) make no wonder they make not much extra poke but good for a supercharged vs I guess

Also I went to enquire about getting a manifold made and got quoted £4-5k!!!

They have already made one for a vr6 and by sounds of it the primaries went down to near bottom of engine

I've got the flanges coming in the next few days just need to learn to weld lol