weber install???

[carrerarsr65]

i have 79 3.0sc putting 40idas on the car do i use the stock throttle linkage/plate on the back left half of the motor,or does that go away ? the manifolds i received with the carbs. seems to interfere with the old cis linkage plate , any help would be great


p/ns on the manifolds are the same and they are 9011083211r

[jbell959]

You no longer need that linkage plate. You need the bell crank that goes on that shaft sticking out from the left manifold. Your linkage connects to that. I can post a picture of the part you need if that would help.

Looking at your pictures again it's hard to tell if you had those manifolds ported to match your heads. Those early manifolds are much too small for your 3.0 heads.

[bgyglfr]

You don't need the CIS plate anymore.

Edit: John you beat me to it.

[chris_seven]

The rod from the Weber Bell Crank that connects to the bell crank on the transmission will also need to be changed or you won't get full throttle.

If you have a Plastic Throttle Pedal the stop on this part may also be too long to prevent full throttle opening.

The manifolds will just about open up to fit but you will need some plates to blank the port for the injectors and gaskets to suit. We opened up the throats to just over 38mm at the base of the manifold.

We made some plates from Tufnol sheet and they worked well.

We have a pair of Zenith 40TIN carbs running on an SC with 10.5:1 pistons, 911S profile cams and it makes around 250 BHP with these manifolds.

We have another Carrera 3 motor which has Euro CIS Pistons and standard cams running of Zenith 40TINs with completely stock manifolds. It has headers and a two in 2 out muffler and a modified ignition curve.

It makes around 215 BHP and pulls strongly without any stumbles.

[G50911]

make sure you get the correct gaskets when mounting the manifolds. i was told that carb manifolds are not airtight when replacing the CIS. check out post #23 on my build thread for a pic...

[chris_seven]

The problem is that standard car gaskets don't cover the port for the fuel injector. If you use a carb gasket it just doesn't seal.

If you use a CIS gasket the shape of the flange on the standard manifold is also incorrect and again doesn't seal well.


The 3mm Tufnol plate we made covers the injector port and when used with gaskets of the same basic shape, which we also made it seals very well

We waterjet cut a bagful of these plates and double the number of Klingersil gaskets at the same time.

We cut them with a central bore of 37mm diameter.

We use them unmodified with the standard manifolds where the outlet is 32mm and fit a gasket of the same size both sides.

If you open the base of the manifold to 38mm the plate would need to be opened as well and they are fairly easy to modify with a dremel.

[jbell959]

Here are a couple pics of the bell crank you need. This is a spare so if you need it let me know.

[Gordo2]

This may help: PMO 46mm Carburetor Installation on 3.2L

Gordo

[haasad]

I had the proplem with the injector cutaways Chris is speaking about too.
At the time the best solution I had available was to fit longer inlet studs cut the flange ends off the CIS inlet runners machine them flat and parrallel to form a spacer that closed the injector cutaway and left a flat surface for the weber manifold to fit on , I used standard heat insulators and, as Chris says, extra gaskets.

No issues at all since.

Incidentally I also converted my throttle to direct pull cable, much less to go wrong and great feel.

cheers Andy

[Lapkritis]

Piling on - not a bad idea to have a spacer between the manifold and head anyway. Phenolic flange insulation will keep some temperature out of the carbs.