How to optimize a Spica injected Alfa

[Rosenmöller]

Hello

Some of you might know me, some don't.
I' m the guy in Germany who is trying to keep his Spica running.

I always had problems to cope with my friends driving around with the carburretor engines. So this winter I decided to do something about it.
I did put in a few questions on this board, got a lot of answers, read alot and finally contacted Wes Ingram what to do.

First of all I would like to say thank you to Wes for his support and his suggestions. All I did was just simply doing what he wrote me to do. I'm writing this with his permission as well.
Second a big thank you to Papayam who supplied a lot of literature especially about camshafts and to Roadtrip for all that he has written for us so far.

My engine is a stock 2 Liter engine from 1974 except for the following things:

Newly rebuild FI pump by Wes Ingram ( Stock)
Bigger Throttle bodies by Wes Ingram
New l-jet tronic Bosch fuel pump Bosch number: 0580464013 ( plus following the whole procedure John has written in his Fuel diagnostic guide )
Spark Plugs NGK BP7ES ( lots of high speed driving on the German Autobahn)


The target was to get somehow near to the performance Alfa Romeo said the car was supposed to have. As we all know there is no stock Alfa Romeo at least at that time with the horsepower standing in the manuals.
Second I didn`t want to spent much money. I actually spent money only for the valve shims and for the dyno to verify the result.

Kompression of the engine between 12,1 bar and 12,5 bar
gives you 169,4 PSI - 175 PSI ( 1 Bar = 14 PSI )

So that is what I did:

I did set ignition maximum timing to 38 degrees.
- I did it with 5000 RPM but there is no further advance at 4000RPM. Listen for pinging at low engine speed with WOT (wide open throttle).

I did verify WOT at the butterflys.
-Use a mirror and center the plates in the throttle bores with the throttle stop screw on the manifold. Have a helper hold the accelerator to the floor. Remove the stop under the pedal if necessary and take out the slack in the throttle cable at the firewall. Loosen the throttle stop at the firewall (unscrew it to allow more stroke). Leave about 2mm slack in the cable.


I did set the intake cam to 102 degree. Exhaust already had the 102 degrees.
- This one is fairly easy I did use the Shankle Camshaft Timing Template. - Originall intake timing is 114°. You find the templates here on the board - somewhere, or you find them on the homepage of centerline somewhere.
- as you see I left the original camshafts in the car. I was thinking about changing - to the desired 105.48.03.200.01 but Wes said with them I would only get - an additional 3 - 5 HP. So I left the original 105.20.03.200.00 in the engine.

I did advance the FI-pump by one tooth.
- This is described in Wes Ingram`s manual.

I did reset the fuel mixture to 1,75 % CO at 2800 RPM.
- Readings were:
- on 2800 Rpm

CO 1,75
CO2 13,8
HC 58

- on idle at 750 RPM

Co 1,90
CO2 12,3
HC 870

- HC on idle is a bit high, I will have to do some more work to get the - throttleplates really closed.

I did reduce valve clearance to .014 on intake and to .016 on exhaust ( or .35mm in and .40mm out) this is not as much as Wes Ingram suggested but I think thats enough for starters. Wes did suggest .12 intake and exhaust .14 .

I did about 7500 Km or 4660 miles with these settings . No problems, and an average of 27 miles per gallon.And the Alfa driven like an Alfa is supposed to be driven.

Last weekend I went to a dyno (?) to verify the results I already felt. The car is performing really good. One of my friends said to me:" Good that you finally installed carburretors in the car", which I didn`t. I could cope with the others easily.

I attached two graphs, but they are of corse in German so the basic achievements:

As for the Horsepower achieved:
It is : 88,7 Kilowatt or 121 HP or 119,4 BHP

The maximum torque is :
179 Nm at 4000 Reffs. Fascinating fact the torque stays always above 170 Nm on the range between 2500 reffs and 5000 reffs.
1 Newton Meter equalizes 0.737562 lbf ft ( poundforce feet )
That will make if my calculator is not lying: 179 Nm 132,02359 lbf ft

Motorleistung = enginepower
Diagram shows the actual horsepower( Red line ) in KW it gives me 88,7 KW on 5030 reffs. Blue line is the loss of power at the wheel which is I think a bit to high with 14,5 KW or 19,8 HP. ( Any ideas for that one?)

Drehmoment = torque

Shows the actual torque ( blue line ) Nm.
And the engine power ( red line )


I`m really satisfied with the achievements made.

Greetings from Germany

Bernhard

[1750GT]

Bernhard.....thank you for sharing this with us. It is a very nice summary of the work you did....I really appreciate it and will be using the same approach for my engine rebuild (except that I've got the 1750 engine). I too will be sending the FI pump to WES (I met him recently at the AROC convention) and what a true gentlemen he is, his shop is probably the only one in the world that I know of that I would entrust the SPICA pump rebuild to. Did you use an engine DYNO or Chassis dyno for the test?

[Rosenmöller]

It was chassis dyno.

With a1750 you will most probably have another set of camshafts.
Just tell Wes want you want to do with your engine, and he will tell you how to do it. And he will rebuilt the pump eaxactly to these specs.


Greetings from Germany

Bernhardr

[Rosenmöller]

Hello again

I did convert the graphs to your standard.
Unfortunately I was only able to do the upload as a PDF.
Maybe someone else can convert them and put them back in.

Greetings from Germany

Bernhard

[gprocket]

[Rosenmöller]

Thank you

Greetings from Germany

Bernhard

[Rosenmöller]

Hello again,

first of all I have to thank Wes Ingram for his great support and his knowledge to guide me through this.

I have done some more work on my engine last Winter.
I just come back from a dyno, so I can show you the results as well.

So what did I do since Post number 1 ?

Basically everything stayed the same and I will only write about the changes.

1 I did install the crane XR3000, but with same timing as above.
2. I did increase the sparkplug gap to 030 in
3. I used my original Marelli coil,, but without the restrictor
4.I did install the A16 camshafts from Wes Ingram.
( 10.2 mm lift X 240 degrees duration at 050in. lift.)
Same lobecenters and same valve clearance as above.
5. I did unsrew the Alt compensator by one turn.
The decel allows linear fuel increases/decreases. The Alt compensator allows very slight exponential changes. In other words if your idle mixture is good but you need a bit more fuel at the top end the decel will not help.But if you unscrew the Alt screw one turn it will not affect the idle noticably but will add fuel when you increase the throttle opening. The horiz lever in the pump rests at a higher point on the serrated lever which increases the stroke or travel to open the plungers. You can view the internal parts on this site: Ingram Enterprises Inc. - Fuel Injection Specialists go to the Spica page, bottom tech information offered by John Stewart.( Roadtrip )

6. I did set fuel mixture a bit richer then in the first post.
Readings were:
at 2800 rpm
Co 2,2%
CO2 13,25
HC 115

at 750
CO 2,7
CO2 11,55
HC 1550

HC at idle is to high. I have to do some work on the throttle plate again.
Attached you will fin two graphs . There you will see in comparison the results from last year simply called Spica2007 and the the results from this year called Spica 2008.

As you can see a good result with the horsepower, but I lost a bit of torque.
Wes did suggest to try increasing the fuel a little (1/4 turn on the decel) which may increase the max torque. This could lower the hp above 5500 though.I will try that later.

Greetings from Germany

Bernhard

[1750GT]

Once again nice hearing from you Bernhard. The work you're doing is great and much appreciated. I like the progress you're making on the engine. How many times are you driving the car weekly?

[superloaf]

bernhard, interesting stuff.

what does advancing the spica pump belt by 1 tooth do exactly? i haven't heard of doing this and i'm curious. did it make a noticeable difference? any info on that or links to more detail appreciated.

thanks, bob

[Rosenmöller]

Quote:

Originally Posted by superloaf bernhard, interesting stuff. what does advancing the spica pump belt by 1 tooth do exactly? i haven't heard of doing this and i'm curious. did it make a noticeable difference? any info on that or links to more detail appreciated. thanks, bob

[Rosenmöller]

Quote:

Originally Posted by 1750GT Once again nice hearing from you Bernhard. The work you're doing is great and much appreciated. I like the progress you're making on the engine. How many times are you driving the car weekly?