Click to view attachment

Hello all! Happy to have this supportive community to help me out with this, as I have been striking out.

I have a '73 914 that I am building. She's a 2.0 liter car with SC flares, 5 Lug Fuchs in Ravenna Green. Her new 2100cc motor is going in this week, and we have a fresh pair of 40IDF carbs to go on it....but no manifolds.

EVERY place I speak to has manifolds that will bolt up (3 bolt pattern), but they are all the cheap EMPI model, measuring 44mm below the carb.

Aircooled.net, Pierce Manifolds, eBay...they are all like this . My understanding is that these larger bored manifolds paired with the 40mm carb output causes air turbulation under the carb which I do not want.

I was running 44's on my last build, 2056...bogged down like crazy below 3k even jetted down..they're just too big.

Soooo....any suggestions on where I might find a set of OLD stock Weber manifolds for 40's?????? Aircooled.net said the only way to make it happen is to sleeve them and seal it with JB Weld....I don't buy it, nor would I do that.....

Look on TheSamba.com

is that a word... if so Im not sure its the one you want.
From where are you deriving this understanding?
It stands to reason that you might want an intake bore the same diam. as the throat of the carb. you are using, but its not like it is a plenum, & wonder how much adverse impact is likely.

Gonna be hard to find manifolds that are only 40mm on the carb side since most were made to fit all sizes of Weber and Dellorto downdraft carbs. The only thing close to that would be the factory manifolds made for the 1.8L engine for the Type 4 Formula Super Vee series. I have a set for sale here on the samba, but they are only 4 bolt (1.7L / 1.8L). The carb side opening is 41mm, and the bolt pattern is for a Solex P11-40 carb.

https://www.thesamba.com/vw/classifieds/det....php?id=2325594

I was able to find a set from European Motorworks in California. Internal diameter: 40mm They are super hard to find.

Turbulation may not have been the word I was looking for...though it seems like not to far a stretch as my intended meaning was: causing air to turbulate, or turning a laminar flow into a turbulent flow....which IS what would happen with a 48mm manifold being fed by a 40mm opening on the bottom side of the carb. Think about it...How can that be beneficial for air FLOW.

Why Redline would market kits that use universal bores for their manifolds 40-48 is beyond me, but my sentiment was corroborated by George Hussey who agreed that this is in no way ideal. I have 2 other sets of manifolds...48s (which redline sells universally now with their kits) and 44s, which would have matched up with the 44 Webers I have....

Glad to be running Weber 40s with the proper manifolds now...

I think it will make a difference because...science.

Brand new

https://www.csp-shop.com/en/engine/intake-m...440-22691a.html

you're welcome



They have the shorties too
https://www.csp-shop.com/en/brand-shops/int...0k3-21127b.html