rs73ca

so sad!

cairo94507

Not getting in the middle of this, but I am curious, what does the MFI weigh?

r911

sent you a pm

myflat6

The heavy part of the MFI system is the mechanical fuel injection pump itself. It is rather bulky at approx 16lbs (estimate based on shipping my pump to Mark Jung). You do get more power and better throttle response with MFI vs. carbs - which is the true comparison of the systems available at that time. It is hard to compare to weight and performance of EFI since there are probably a lot of variables that will come into play for someone doing that upgrade. For example, are they modding the stock TB's or adding new with fuel rails, the additional sensors, wiring, controls - and many will upgrade to twin plug, which also adds weight. Is EFI with dual plug superior than stock single plug MFI - yes from a pure performance perspective. However, many of us own these old cars for the vintage experience and appreciation of Porsche engineering history. Any of today's grocery getter cars have EFI, so what type of experience are you looking for in a 50 year old car? Some of us want something different than the technology that a Toyota Camry has (BTW, let's not kid ourselves with the performance of most of our vintage Porsche's - most of today's typical production cars can outperform them in some areas anyway). I am not an EFI hater - the reality is you can build an awesome and superior motor using EFI -- I just think the argument here shouldn't be what system weighs more less - it all comes down to the experience you are looking for. For me, I want a throwback experience and I want to own something of the past - Porsche engineering from a time that is gone but I can still appreciate today when I step out of a modern car into my old Porsche. I would buy a 991 if I wanted all the modern tech advances and improved performance, but that is not what I am looking for in my old car.

myflat6

I would trust Randy's data - he probably has this broken down to all of the components. I know his approach is very much oriented to less weight - improving power to weight ratio. Nothing wrong with that. Again, all depends on what experience you are looking for and your objective with your build.

r911

Yes, I'm a hotrodder. I agree with your post above and also seek a sporty vintage experience. An evolved one - with suspension upgrades that Porsche might do these days. At some point you buy a Singer or pay a visit to Alois Ruf or Robert Linton (who recently posted to his thread BTW) tho. I wanted to build a car myself and make it as light as I could at reasonable cost. If I were the CEO of Oracle I'd build the unit body out of carbon fiber (instead of $$ on fast sailing yachts). In a decade or so, all IC motors will be vintage efforts.

I researched MFI extensively years ago, and finally went with PMO carbs. You could get Motec back when I looked at this for my own car but the cost, and difficulty of working on the system on a lonely mountain road miles from a cell signal made me go with carbs.

Today, I might just go with EFI and a Mg cased motor instead of the 3.2L I built. The EFI in an MFI disguise is a viable option if you want that look. IIRC, it is a Gamrothian product.

OTOH, you might want one of each... The look & feel, the experience is what I and many others are after. It is almost like a piece of HiFi stereo equipment - the looks and the ergonomics are important once you are in the same performance ballpark of various units.

myflat6

^^agreed!! Isn't this much more fun to talk about our beloved Porsche's to distract us from this crazy situation our world is in right now!? There is no right or wrong answer to these things - many flavors to suit your desires.

myflat6

Oh, and by the way - there is still quite an interest in MFI. I reached out to Mark Jung earlier this week to find out where the heck my pump was. He told me he has 15 pumps lined up for work and is booked out for months - not even feeling the impact of Covid-19 on his business. My pump is being worked on now and will hopefully be done in the coming weeks.

r911

I look fwd to seeing your thread being updated - was going to post an old pic of Mark but this web site hung on it...

myflat6

I am really hoping to make more updates to my thread soon as well - things have just gone much more slowly than I ever expected. John Dougherty told me my cams ship today or tomorrow. Will post an update when I receive them.

zkaleem zae

Quote:

Originally Posted by CPMorey

I'm looking at a '72 hotrod w MFI. The 2.7 liter is actually more like 2.9.

I've heard that the MFI can be tough... e.g hard to find people to work on them. Especially when the displacement isn't stock and the MFI hasn't been tuned for it.

Anyone have experience to share? What should.i be asking about? How

Some people like to keep a car original for aesthetic reasons. Unfortunately, others "are not about to ruin [their] car's value" and are only in it for the money