jacksonrw

I am redoing my daughter's 914-6 I built for her

currently the 2.4 liter is fueled by 2 triple throat webers. She hates the backfiring and the black smoke - so I am considering switching to fuel injection - no clue how or where to start

also

there was a great thread once started on adding the modified brackets to have an a/c compressor to the 914-6 engine - i cannot find it. Please help

racer

The carbs shouldn't be backfiring and smoking.. You need to get them sorted out/rebuilt/rejetted etc. Carbs, then tuned properly, work great.

IIFC, depending on the motor, your choices are either MFI (which, iirc is frightfully expensive as all the longhood 911 crowd has been buying up the parts) or CIS. And I have no idea which would work as a "simple bolt on" to a car that has carbs.. ie, camshafts, fuel pumps, electrical relays/lines etc. There "may" be some aftermarket EFI kits that could help.. but then again, you could spend your time being the "test bed/ R&D" for such conversions.

I certainly think that fixing the carbs to be the cheaper and easier way to address current drivability concerns.. or sell it all and have a shop charge 10K for a 911SC engine conversion.

hitbyastick

What racer said ... Carbs that are tuned properly shouldn't smoke. Except smoke a 4 cylinder 914
Ok all joking aside. I would think that going Porsche/Bosch is going to be an expensive undertaking. CIS may be the cheapest way, but that's a system I don't actually understand that well.
If you really got a lot of time you can use Megasquirt.

jacksonrw

i will consider megasquirt

any good books to recommend on overhauling these carbs
they have been in operation only 2 years since they were completely rebuilt by my friend

the fella in dallas did the a/c thread I cant find....anyone have a clue

hitbyastick

I know Haynes makes one. They should be able to order that at any automotive store.

Sorry, I can't help with the A/C questions. I'm sure you've seen this on pelican:
http://www.pelicanparts.com/techarti...ult_AC_faq.htm

Ron_H

Haltech. Didn't they cooperate with some manufacturer at one time to produce FI using individual throttle bodies? I recall a system that was competition to the factory MFI and produced great amounts of power. Why not contact them and ask? I Googled them but noticed no mention of such a system.

I have a 2.7L RS original MFI pump and throttle bodies/intake stacks and only lack the fuel supply lines. I would trade it for a Porsche GT-1, and a 906. Otherwise, I'll keep it......forever.

skl

Excellence magazine has an article this month about aftermarket FI for 911's... might be worth a look.

jimbo3

Did anyone tune the carbs after your buddy re-built them and they were re-installed? If not, that's probably the problem.

Rebuilding is pretty easy. Remove carbs from manifold, take everything apart, thoroughly clean the body by soaking in carb cleaner and then blow out the passages and jets with aerosol carb cleaner, and put everything back together using the new parts from the rebuild kit. Initially, turn the main jet screws (Thumbscrews) in all the way and back them out two turns. Turn the air correction jets all the way in until they seat. Install the carbs back on the engine, warm it up, then start the usual tuning process. I never needed to remove the butterflies, throttle shaft or bell crank, but you may need to if they are all gumped up.

While everything is apart, check jet sizes and emulsion tube numbers and compare to what "stock" should be. Might have some issue with the accelerator pumps/jets or the wrong emulsion tubes to get the black smoke. That could account for the backfiring, too. Ignition (points, condensor, coil, wires, plugs, timing) could also be the problem.