2.4 question... from carbs to MFI or EFI?

[lvporschepilot]

Those cycle TBs are a great way to go. A friend of mine installed Suzuki Hyabusa TBs on his Ferrari 308 2v engine and is currently in process of tuning the machine, but boy does it run. The manifold definitely took some time to negotiate getting the TBs to play nice though.

[Henry Schmidt]

Sometimes the question is not so much can you do it but should you do it.
I've worked on this particular engine in this particular 550 Spyder replica and it seems just plain goofy to install an EFI with a set of Triumph throttle bodies in this application.
The Spyder is a unique little car that has historical significance and a price tag that is difficult to overcome so these replicas are the closest thing most of us will ever get to owning one.
Having rebuilt the original 4 cam engine in the first 550A Spyder produced by the factory, I have a special affinity to this model. That said, keeping the driving experience and aesthetics as period correct as possible seems appropriate to me. I prefer building them with 4 cylinder engines (upright fan type 4 or a Polopolus 4 cylinder 911). They sound and perform correctly but a mild 911 works reasonably well. Carbs complete the package.
Opinions will vary.

[x98boardwell]

Henry,

The first two photo's is my car... You worked on that for Ed prior to me buying. We spoke on the phone about 6 months ago when I purchased the car from Ed.

Thanks for sharing the pics.

Cheers,
Bryan

[Henry Schmidt]

Originally Posted by Raceboy

....snip....

P.S. If it's ok, I would propose concentrating more to technical stuff and not personal attacks?

Racerboy
When you've worked on these engines for more than a minute perhaps you will be qualified to make suggestions on what or how I post.
Many of the members on this and other forums have benefited from my willingness to share my expertise as well as innovative products and some have even benefited from a suggestion or two (generally in good nature) about toning down the unabated arrogance.

Originally Posted by Jeff Higgins

Henry, with nowhere near your experience in this game, I did find my LM-1 to be invaluable in setting up my MFI pump on my oddball 3.0 build. I think what this kind of technology has done, if nothing else, is open this up to duffers like me who like to fart around with this stuff. All it really takes is a basic understanding of how the system works, too much idle time, and an LM-1 to tell a guy what is happening, and most anyone with any sort of common sense can make this system sing. And I've had a ball doing it.

Jeff
You know my work and my postings well enough to know that my comments were not meant to challenge the value of test equipment.
The statement challenged the assertion that without it you can not properly tune an MFI engine and the suggestion that most who try, fail.
I own an LM-1 and have for many years and find it an unnecessary tool for tuning MFI but because I have 30 years of experience that dates back to when these cars were new, perhaps I have, as many do, an insight as to the tuning foibles of the MFI Porsches.
Use whatever tools help you accomplish your goal with my best wishes.

[Jeff Higgins]

Originally Posted by Henry Schmidt

Jeff
You know my work and my postings well enough to know that my comments were not meant to challenge the value of test equipment.
The statement challenged the assertion that without it you can not properly tune an MFI engine and the suggestion that most who try, fail.
I own an LM-1 and have for many years and find it an unnecessary tool for tuning MFI but because I have 30 years of experience that dates back to when these cars were new, perhaps I have, as many do, an insight as to the tuning foibles of the MFI Porsches.
Use whatever tools help you accomplish your goal with my best wishes.

Oh, no problem at all, Henry - I do know your work and your posting well enough to know what you were driving at. Hell, we didn't have this fancy tuning stuff (at least readily available) as recently as what, ten years ago? My God, how did we survive?

I was brand new to the wonders of MFI ten years ago. I had been tuning carbs on virtually anything with wheels for 25 years, with no more sophisticated "test equipment" than my right foot (or wrist), my ass, and looking at spark plugs, and I did just fine. We all did - we had to. I'm sure that's how you learned to tune MFI as well.

When I first started farting around with MFI on my old 2.4, I relied soley on that old "seat of the pants" and plain common sense. Even when I started in on my oddball 3.0, that's how I first began (and lots of phone calls to you, if you remember any of that). In the end, I went to the LM1 so I could see, graphically, right there in front of me on a computer screen, what guys like you can "see" through the eyes of experience. I just didn't have that experience with MFI to do it any other way.

So, in my case, the LM1's value was that it served to help fill in for my absolute lack of experience. It was a valuable shortcut to seeing how MFI reacts to various tuning changes. For a guy like you that knows the system inside out, backwards and forwards and upside down, your experience with it is far more valuable than any data collection instrument. Anyone who says a guy "needs" these instruments to be successfull really just hasn't been at it long enough. Experience is certainly a more than worth substitute.

[x98boardwell]

Anyone know a good tuner... as close to Fresno, CA as I can get? for carbs? Just in case I need to call someone that I could actually drive the car to.

Thx,
Bryan

[lindy 911]

Bryan,

Performance Oriented, Henry and maybe the guys at PMO can get you very close with engine info (CR, cams, ignition) The fine tune is not that hard. It's a matter of spending an hour or so with an air flow meter in each bank and then fine tuning the idle circuits with the adjustment screws. I'll bet you could do it yourself. You'll need an air flow meter sold by Pelican and a little help from this forum...

[Raceboy]

Originally Posted by Henry Schmidt

Racerboy
When you've worked on these engines for more than a minute perhaps you will be qualified to make suggestions on what or how I post.
Many of the members on this and other forums have benefited from my willingness to share my expertise as well as innovative products and some have even benefited from a suggestion or two (generally in good nature) about toning down the unabated arrogance.

And now you know how long or what I've done on 911 engines, right?
With your last post you have lost any respect in my eyes but that shouldn't bother you a bit, who am I to judge anyone, especially Henry The Great, right?
Lets just drop this and try to get along, or would that proposition also not qualify due to my "rank"?

Regarding the "should one do it", I already mentioned already before: EFI is a good choice unless someone wants to retain period correctness. I personally don't think also that 550 Spyder should be equipped with EFI.

My main point regarding tuning equipment was that you can do it less effort, with less risk and get better results. I have seen too many engines having blown pistons because someone thought that it runs well by just driving it prior to properly tuning it.