MFI PUMP or WEBER CARBS ???

[s-bonhomme]

Hi, I need help, I have a 911S 1971, and I have the original MFI and a set of weber 40IDA, which one should I used ??? and where can I get info on how to install it. Thank you

[Steve@Rennsport]

You should install the MFI as long as its in excellent condition.

I'd recommend the factory workshop manuals for this job.

[haycait911]

Originally Posted by Steve@Rennsport

You should install the MFI as long as its in excellent condition.

I'd recommend the factory workshop manuals for this job.

what he said. you can run the webers while getting the MFI refreshed/rebuilt. or at least carefully checked over. there's a couple of places that can do that for you. in the end, the car should be as original as possible, meaning MFI.

[SM911]

Agreed...
Had the MFI on my 911/83 (2.7 RS engine) rebuilt in Oct, and the throttle response is absolutely sensational.
If your MFI is serviceable (or you have the ability to make it so), it's (IMHO) a no-brainer. And, it keeps the car original, just as the S was designed...
You won't regret it.
SM

[lateapex911]

Webers.
And send that old MFI boat anchor to me.

I might even send some cash your way in exchange.

If you love dorking with carbs, then I guess carbs could work. And if your MFI needs any work, and you're short on cash, then carbs.

But, if the car has the proper cam, and is original and the MFI is in good shape, then yea, it's the only answer.
I wish my 73 still had it.

[RWebb]

find the Check, Measure & Adjust thread and manual -- read it carefully

MFI is harder to setup than carbs -- if you are not near a good Porsche 911 mechanic who knows how to do MFI, then you may want to go with carbs

MFI is also pretty heavy (it is a diesel tractor pump, after all) so that is a 2nd factor against the benefits of MFI (one not mentioned above is cold start & cold running ability)

you can always ship the MFI system across the border to get it completely fixed up - you would then "just" have to install it and set it up on the motor

post a pic of everything to make sure you have all MFI components

[RWebb]

BTW - another issue could be ethanol (Et-OH) in you gas -- not sure what they do in various parts of the Great White North...

maybe Steve can tell us if carbs or MFI is worse on an Et-OH mix...

and... this is a very good time to replace all the old, dangerous rubber fuel hoses on your car with something rated for Et-OH -- the SAE spec. could be J30R9 or J30R7

[regency]

The best thing you could do is install CIS............kidding, go with the original MFI.

Steve

73 911 T MFI Coupe, Aubergine

[RSTarga]

MFI when rebuilt correctly and setup correctly is relatively trouble free. + the performance is really outstanding. If you don't know the condition, spend a little upfront and send it off to Gus at Pacific Injection for a rebuild. Once you've done that make sure your throttle bodies are in good shape Eurometrix rebuilds these and your good to go for many many years.

[regency]

Gus rebuilt my MFI Pump to "E" Spec, Matt Blast @ Eurometrix re-built my "T" throttle bodies to "E" spec. Runs great.

Steve

73 911 T MFI Coupe, Aubergine

[Rexs-911T]

Send me the carbs rather than putting them on the shelf if you go with MFI :-). Looking for some Webers on a new build of mine.

Rex