MFI just installed in my 73S, it's like a completely different car!

[neilk]

After having a nearly complete MFI setup in a box for 10 years, and carbs since I bought my 73S in 1994, I finally finished installing the MFI today. The engine stalls if the revs going under 1500, but over 1500, it revs like a beast. I went for a short drive around the neighborhood and was amazed at how smooth and responsive the car was. It's like a a completely new car.

I will spend some time this weekend trying to dial it in using CMA, but will probably bring it over to Ed to fine tune it and make sure I didn't overlook anything.

More to come, but thanks to Mark Jung for checking out the pump and replying to my e-mail when the car wouldn't start. He was right, it takes about 2-3 minutes of cranking a completely dry system before the injectors would spray gas.

Looking forward to putting some miles on the car!
Neil

[72targa]

Congrats! Let's see some pictures!!

[Biancaneve]

Good news, love MFI!

[Haasman]

Neil- I did this. It really makes one appreciate these engines. Different driving experience.<script type="text/javascript" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/482a022b/background/helpers/prefilterHelper.js"></script><script type="text/javascript" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/482a022b/background/helpers/prefilterHelper.js"></script>

[tomster]

My 1970 2.2S had carbs installed when I bought it. Actually still has, though the complete MFI setup is sitting in my garage waiting to be installed.
But I am no longer sure to actually do this because a couple of friends who drove it said that the carb-setup is pretty much fantastic. The car is rev'ing really well and even has a perceptible "extra boost" when coming to ~5.000 RPM. Dunno if there have also been performed alterations to the cams though as I did not open the engine yet.
A rally driver (though not racing Porsches) who adjusted the chassis setup would have even guessed that it has considerably more than the 180 MFI-horses.
Since I didn't have the opportunity to drive a MFI-one for comparison yet I end up pretty torn whether to get it back to stock it or leave it as it is for the time being...

[edmayo]

That's what 'S' cams feel like, with either carbs or MFI. If you're happy with it leave it alone,,,,,just don't ever let go of that MFI system for that someday when you sell the car.

[tomster]

Thanx Ed,

that is pretty much what I managed to agree myself on, not the least after your posting above. Ok hardly, cuz me being more of the bring-it-back-to-stock kinda guy.
But I surprisingly do feel pretty comfy with the engine behaviour as it is.
The MFI (though sadly not the original that came off the engine) is all pampered up in my garage. Hopefully I will never be in need to actually have to sell the car... *keep fingers crossed*

[Dmill]

If you think your car runs well now.....wait until the Jedi Master Mayo spends some time with it....

[neilk]

Carbs on my car never seemed to work right. They probably should have been overhauled in the past, but never did it. It seems like anytime they were dialed in, within a couple of hundred miles, they would revert back to anemic state. Except for poor idling, and same backfiring when letting off the gas, the MFI runs really strong all the way to redline.

Couple of questions, when I first got the car engine start, I diverted the cold start fuel to an 8 oz bottle and filled it twice before the pump got all the air out of the lines and started. I would like to convert the fuel solenoid to a push button setup, but did not see any write ups. Does anyone have a link? Perhaps I am searching for the wrong terms. In the meantime, to bypass the cold start, can I loop the two lines at the top as shown in the picture below and have the MFI pump return directly back to the tank as shown in the picture below? That is how the console was plumbed with the carbs.


I will set it up correctly later once I get the idle situation sorted out, and I need to get proper norma clamps on those hoses!

Thanks,
Neil

[edmayo]

Neil, if you want to disable the cold start just pull the grey wire off the top of the solenoid valve. I've never done the first start method you used, I just run a jumper wire from one of the hot fuses on the relay board directly to the solenoid spade. Each time you energize the solenoid fuel squirts into the stacks, just keep doing one second squirts until the engine starts. Look forward to getting that system working correctly for you, as you've already seen, it is the way to go!