2.7RS Clone w/Webers - install
 

Well, it's time to dive in here. I've purchased an RS clone 2.7 and am in the process of removing the original 2.7 from my '77 S project car. The existing motor is original including a 5 blade fan and 7R block but has leaking valve guides in 2 cylinders. The RS spec motor I purchased has 40mm Webers, while the current motor has CIS. Long term, my intent is to rebuild the original (with upgrades and performance improvements) and put it back in when the RS gets tired.

First off, was wondering if there is any performance benefit to swapping the CIS onto the RS clone motor ?

Second, if I stay with the Webers, is there any wiring diagram or step by step procedures to guide me in wiring and setting up for the new motor ? Oh, and what about tidying up things-what can I remove to tidy up assuming I stick with the Webers ?

Keep the Webers - If it's a true RS clone with S cams and RS pistons, putting on your CIS would not work so well. The S cams would be too aggressive and the pistons would not be optimal for the CIS system.

Regards,
Andrew M

Some of the new motor details: RS pistons, webcam#120/104 grind, updated 930 oil pump, 40mm webers w/updated venturis

Sounds like a nice engine - don't put the CIS on it :)

I removed stock CIS engine harness and just wired in a MSD.

You should also have the Bosch pn 0 231 184 004/ 2.7 RS/ '74-'76 Euro Carrera distributor? I removed points and run Pertronix.

Use the webers and install an MSD box and blaster 2 coil. Depending on your distributor, some kind of points replacements also. You need to sort out your spark before tuning the webers or you'll be chasing your tail.

You can sell off your CIS, if you put it in storage be sure to clean out the fuel head first as it will get ruined with varnish and its one of hte most valuable parts.

Wiring Diagram Needed '77 911S RS Clone
 

I've got a petronix in the distributor, just purchased an MSD 6200, blaster coil and tach adaptor as recommended here. Can someone help me with wiring diagrams for a '77 911S with CIS ? The electrical area is a rat's nest at the original fuse block and CD box, the car has clearly had previous mods and to do this proper I'd like to identify everything that is there and/or missing before I tackle installing the new motor.