Motronic FI for Dummies?

[Paradiso]

Hey all you FI geniuses out there (Eric!). Anybody have any book/resource suggestions for the Motronic FI on my 92 Spider.
I want to start futzing around with the engine and I really need to educate myself. Before playing with any modifications, I want to be sure that its tuned to spec (or better).
IAP has a book in the back of their catalog, I think AROC offers a pamphlet, any recommendations regarding these?
Any help gratefully appreciated.

Thanks

John

[turbolarespider]

There are a couple of books out there that cover the Bosch injection, but am not sure how good they are for modifications. From what I've looked at, and the reviews at amazon, both books cover how the various systems work:


Bosch Fuel Injection and Engine Management
by Charles O. Probst

and

How to Tune and Modify Bosch Fuel Injection
by Ben Watson

What you will find is that from a computer standpoint, it will be very hard to modify the module. The MAF system that it does use should handle the basic cam changes as well as a better exhaust, but radical cams will be difficult. One thing to keep in mind is that these late cars make as much power as the early SPICA cars, but are about 20 times cleaner. So they do a good job with the power.

What kind of things do you want to do?

Eric

[Paradiso]

My biggest issue with this car is the lack of power on the low end. So I'm just absorbing all that I can about different ways of making power from this engine. Since this ain't never gonna be a track car, I would gladly trade top end power for more torque down low.

After working extensively on my suspension, I understood that I had no idea how an Alfa really handled. My car now bears no resemblance to the car I bought 2 years ago. So extending that to the engine, I'm not sure that I know how much power this engine really puts out. I want to understand enough about the functioning of the FI to get the engine running the way its supposed to and then start to make decisions about where to go from there.

Does that make sense?

[turbolarespider]

I see.

The books that are available might not cover the VCT system that your spider has, and that would be a contributor to not so good low end power.

Does the car hesitate at all? Or drive funny? For the most part, everything is timed by the computer, so you can't really advance the spark, or add more fuel (which probably wouldn't help anyway).

Too bad you don't live around here, it would be good to comapare to a known local car to see if there is a problem or not.

I'm not even aware of many things one can buy to gain more power...

Eric

[Paradiso]

There are 3 things I'm looking at:
1) More air in - Thinking along the lines of replacing the air box with a K&N filter and locating it low in the engine compartment to try to get cooler air. I'm not convinced that would be better than the stock air box with the engineered in cold air inlet.

2) Freer flowing cat/catback - Again I'd have to be pretty sure that I could improve on the stock design before messing with it. The exhaust manifold seems pretty good so I probably wouldn't mess with it.

3) Chip from Squadra Tuning.
Squadra Tuning Dyno chart

4) Yanking the A/C compressor and all related crap. Nobody but me thinks its a good idea but I'm very tempted. This weekend I'll be installing a belt that will take the A/C compressor out of the loop. To me its just a lump of metal wasting power.

As I'm considering these ideas I want to get a lot smarter about how the engine in my car is SUPPOSED to work. Hence my starting this thread.

Thanks for your patience.

John

[AlfaTaso]

If you are unhappy with how your Alfa performs when in stock spec, I think that you should consider getting another Mitsubishi instead of screwing up a good thing.

My advice: bring your car to perfect stock with factory Or Better components, then enjoy it.

Cheers

[John M]

Hey Taso:

I kind of agree with what you are saying and see where you are coming from, but then again I also disagree. I often cringe when thinking about changing something. When my old shift knob turned white on my 78 Spider, I really didn't want an aftermarket one.....even as nice as my new one is and even though it perfectly matches the steering wheel. But I have grown a bit since, and the knob grew on me. So, yes original is more valuable in most cases, but not always better mechanically and performance wise.

I will disagree in regards to a good balance of performance and drivability. Certainly Alfa handling can be great. But its lack of stock power against present day competition is very evident. Even in their day in the 50s and 60s they still were by no means the fastest car on the block. An Alfa can be though a very nice predictable car that feels as though its on rails. But, to get there you have to replace the US taller springs and utilize a more modern higher performance shock, etc.

Can we improve a mass produced engine? Yes, and this goes for just about any manufacturer. The factory architect designs the first and then its off to the assembly line where the Italian version of Bill and Ted get hold of it. Should we use stock Alfa valve guides, when we know they frequently fail and are not the quality of the aftermarket supplier? I think not. Can we balance an engine better than one pulled off the Alfa shelf? Most definitely. The Alfa engine design was certainly way ahead of its time when it came out. DOHC, a timing chain, easy head removal are things I really love about it. But the one in my 92 Spider is basically the same engine as in my 78 with different fuel and fire delivery. Modifying the engine with higher compression pistons, balancing the components to higher tolerances, utilizing better, lighter rods, larger valves, better cams, better valve springs, improved cooling, oil jets, larger intake and exhaust ports, exhaust manifolds, etc only brings the massed produced Alfa to the "Golden Mean". A truely wonderful balance of performance and handling and drivablility.

I certainly disagree with you on this:

Quote:

if you think that you are better than the factory architects in designing your engine, then you really have no bussiness being in an Alfa engine to begin with;

[AlfaTaso]

John, Paradiso, isn't going to race a Series 4 Spider. Also I didn't say that you cannot make a Spider or any Alfa for that matter faster; but you have to trade something for that. And most of the time that is drivability. If you change the suspension so the car handles better, then you have a hard (or harder at the least) riding car. If you balance it and blueprint your engine to make it more efficient; you have my blessing ,(like I said before) but when you add higher compression, and higher lift cams bigger intake bigger exhaust, you are changing the parameters of what makes that PARTICULAR CAR FUN! This is a fact, and not my personal opinion.

I am not only sure; I am positive that your Spider is A BLAST to drive. I would absolutely LOVE to take you up on your offer and drive it as I'm sure that it's the fastest '78 there is.
But understand what I was trying to point out:
You can't expect to mess with a stock Alfa and make it a "better" car. ("Car" being all encompasing)

P.S. Do you have the "Owner's Bible"?

[Roadtrip]

I'm not sure you're going to be able to do much with a Motronic engine other than maybe a performance chip. And if MA is into your car's exhaust pipe as far as its tax collectors are into its citizens' pockets, then mod'ing the engine may not be practical.

Maybe . . . . . . the solution is . . . . drum roll, please . .TWO Alfas!Now I know this is going to be a hard sell on the spousal unit . . . . but it can be done.

Why not leave the Series 4 car as the Sunday, go-to-brunch cruiser and look around for a early 70s Kamm Tail with a good body and bad engine. Think of it . . . . . rebuilt with hi-compression pistons, some 11mm lift street cams, side-drafts or a Ingram HP 150 SPICA pump, balanced, polished valve cover, etc.

Or . . . . . maybe an extra drop in performance engine for the Series 4 after all.

[John M]

Hey Taso:

You will have to take me up on the offer. I always enjoy breaking bread with fellow Alfa owners.

I certainly respect where you are coming from and I think I better understand your vision for your cars. I certainly swing back and forth myself on modify or retain as original. My car for the most part looks very stock. Its not until you pop the hood that you can really get any clue that some work has been done. And I really like the fact that it does not look like a modified hot rod. But really I think you would be very pleasantly surprised with the drivability retained with some of the mods we are discussing. Even with my engine done to the 9th degree, she is super easy to drive. Suspension is going to let you have a late 80s sports car feel, nothing that will beat you to death, but the dividends in less body roll are dramatic. It really gives you some confidence and predictability in taking corners. And power is heavenly.

But perhaps I am not getting what you are trying to say. Ok....I just read your last sentence about ten times. Got in a Zin mood
and I think I get what you are saying.

Here is my response
You can't expect to mess with a stock Alfa and make it a "better" car. But.....Grasshopper, you can't expect to mess with a better car than a stock Alfa!

In seriousness, I don't have the Owner's Bible, but would love to read it. You bring it when you come. You can drive, and I will read.

Best Regards,
John M

[John M]

RT does have an excellent point. Cannot beat a second Alfa. And who could possibly find a problem with such a solution. There is a nasty little side effect of this solution that is very common. The spousal unit will begin to accuse you of loving your Alfas more than her. Then the next thing she will do will be to stand in between them and say "his and hers" slotting you for the 70s ride. Then she will pout when you snap back and go "his and HIS!!!" So beware, live long, and prosper.

Best Regards,
John M

[turbolarespider]

I'll also somewhat disagree with you Tsao (sorry I've been off line, but we were in the blackout).

IF you understand what compromises were made for a particular "golden mean" then one should be allowed to make decisions to shift those compromises.

For instance, looking at the data the chip provides, understanding that more than likely, Alfa calibrated the engine to 1) never knock, and 2) over cool the catalyst system, I can see that the chip would both advance the spark for premium pump fuel, and take out a little fuel. Both of which would increase power across the board. I know I would have calibrated it like Alfa did knowing what I do know, and the level of technology that Bosch had available for the early 90's.

Or how many people do you know who re-adjusted their cam timing in the 70's? Where the engines might have been over compensated for emissions?

But you are right- to assume the engineers made bad decisions is wrong. All I would do is shift the known compromises.

Dream car to leave in vacation hot spot for me: Berlina, early 90's Motronic engine, controller of my choice (not Bosch, but one I can change ), modern a/c, perhaps even auto, but not likely. That way I get the early 4 door sedan, with modern emission controls that I know everything about. And a good a/c system to boot.

BTW, I looked at the "Tune and Modify" book. Don't bother. Has a page and 1/2 covering Motronic, and not in accurate detail either.

Before you start throwing parts, do the same that you did with your suspension, and as you indicated you wanted to do- check it over and make sure everything works as intended.

Eric

[Paradiso]

Wow, this thread sure got busy all of a sudden!

Taso, If you go back and read what I wrote initially, you'll see that the reason I started this thread was because I want to educate myself about how to get the motronic tuned to exactly the factory spec. Before touching anything, I want the car to be what Alfa engineered it to be.
I will tell you that in the series 4 they put in a lot of sh*t (there is no better word) that made the car much heavier without any real increase in HP to compensate. Alfa engineers were not gods and like any company, marketing and engineering don't have the same goals. Many times marketing wins (series 4). This whole "Alfas are sacrosanct" horse****, is just that.
I don't pretend to know more than the engineers who designed the cars, that's why I'm here asking questions. I think its foolish to say that the car was the pinnacle of automotive engineering the way it rolled out of the factory and anything one does to it is wrong.

RoadTrip - Emissions testing is a major issue as MA has the same standards as CA. A chip is easy enough to swap out that just replacing the stock one on the way to get the sticker is viable. Headers I think are completely out of the question, a different cat and exhaust are feasible.

Maybe a 1750 is in my future (EMISSIONS EXEMPT!!)

Any way, I don't hate my car, I'd just like it to have a little more coglione at low rpms.

PS - We have way too many Johns on this board
PPS - Don't talk trash about my Mitsubishi!

[AlfaTaso]

What is comes down to I guess is you deside what you want to use the car for and you go from there.

I was working all day on the 164 again putting in a new exhaust so I don't have a lot to contribute right now.

No hard feelings I hope gents.

[Paradiso]

Its all about sharing ideas among fellow enthusiasts. We all have our perspective and most of you know more about cars and Alfas than I ever will.

I promise I'll check in with the board before I install the big aluminum wing on the back!