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Probably, unless they changed the harness, but since there is a jumper I'm guessing they didn't.
Add the O2 sensor and add a jumper and you're set.

The knock sensor is probably only there for protection, if you use poor fuel quality the knock sensor lowers the ignition but it's unlikely that it tries to optimize the ignition. Probably the ECU just follow a base map (that you select with the jumper).
That's my guess anyway...
 

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Craig said:
G'Day Bruce,

See my site (in my sig) for the "Alfa 75, Twin Spark 'S' Version with Catalytic Convertor" manual and a description of the plug/jumper.

Wiring diagrams in the manual show the O2 sensor (S10).
G'Day yourself! Seriously, thanks for the link. I've never heard of the "S" version before. This should be interesting. Good, reliable information is always the hardest to find and this looks like both. I'm glad I had a T1 to do the download though.
 

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Charlie Rockwell, friend, engineer and former full-time dyno tuner par excellence always said to multiply rear wheel horsepower by 1.28 to get flywheel horsepower.

That being the case, the car that measured 94 hp at the wheels has 120 flywheel hp. The 146 hp car has 187 at the flywheel.

My new 2-liter street motor has 10.4:1 Borgos, a big-valve ported head, Weber 45's, Megacycle 11mm cams, and aluminum flywheel. When tested recently, the dyno didn't like the old electronic ignition -- which turned out to need replacement -- but on our one and only good run, we got 127 at the wheels, or 163 flywheel hp. That was with the advance about 8 degrees retarded, pump gas and full exhaust and intake systems. It should do much better now with the new ignition, correct advance and a few miles on it.

By way of comparison, several years ago Charlie tested the car's previous motor when it was in excellent tune. The Tom Sahines-built 1750 engine pulled 108 hp at the wheels (138 hp at the flywheel). It was stock except for electronic ignition, low restriction air intake and Shankle 8L cams. Charlie said the engine was extremely healthy, compared to similar motors he'd tested.

Wouldn't it be fun if we could set up a web page so that everyone who has a dyno sheet can share details about horsepower and torque, along with how the engines are set up? That would be especially helpful for all who are pondering engine mods.
 

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G'Day Again,

Bruce Colby said:
I've never heard of the "S" version before. This should be interesting. Good, reliable information is always the hardest to find and this looks like both. I'm glad I had a T1 to do the download though.
I had never heard of an 'S' version either and I own one.

Apparently a TS with a cat, O2 sensor and a fuel vapour emission control system is a type 'S'.

And my TS was made in Nov 88 so whether or not a TS had an O2 sensor was based on where and when it was sold.

Also there were only 3 (maybe 4) eproms (chips) for the TS ECU and again these seem to be in all countries. Before you ask, RS racing says there is no difference in performance.
 

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"Wouldn't it be fun if we could set up a web page so that everyone who has a dyno sheet can share details about horsepower and torque, along with how the engines are set up? That would be especially helpful for all who are pondering engine mods".

That would be great!. I'm pondering a different engine setup for my SCCA D Street-Prepared autocross Spider, and will do some baseline dyno runs at a local shop (as well as a little tuning). The 1.28 multiplier for rear wheel-to-flywheel power is also good information.

This would be a great new forum topic, even though differences between dynamometers might skew results. Maybe there could be another column or two for test parameters like altutude, ambient temperature, humidity, make of Dyno, etc.
 

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One more bit of random info. The Sprint air intake system that International sells looks like what I bought from Ricambi 15 or 20 years ago. Charlie was sure I had wasted my money, so we tested the stock intake and 8L cams against the Sprint intake and 8L cams. The Sprint setup was good for 5 hp.
I believe Shankle claimed 13 hp for the 8L cams.

GW
 

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1.28 multiplier means a 22% loss in drivetrain. Seems high. I asked Beninca motors (www.beninca.com.au) and he says, on his dyno, for a RWD car 17% loss is more of the norm (or a factor of 1.2). Most magazines also say the same (like that means anything...)

The 2.0L cars seem to be a little down on power, especially the race 2.0 TS. The 1750 race car which registered 131 bhp on the dyno is impressive! The new Civic Si (2.0 iVTEC) motor also produces that much at the wheels! I should really dyno my car soon.

I'm pretty sure with proper fuelling the power would be restored.

Bruce,

You should really put in an aftermarket EFI :) . I have a lead on an Autronic SM2 for sale for US$1200. If you sold the webers and adaptors you could probably pay for half of it already. With EFI you should be able to make 130+ reliable bhp.
 

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75evo said:
Bruce,

You should really put in an aftermarket EFI :) . I have a lead on an Autronic SM2 for sale for US$1200. If you sold the webers and adaptors you could probably pay for half of it already. With EFI you should be able to make 130+ reliable bhp.
Something was definately not right with the setup. The MagnaFlow tech handed me some pieces of exhaust/muffler baffle that he said came out of the tailpipe during the runs. That sure doesn't seem like a good thing. It's odd though because the muffler only has about 10 hours on it. Also, there is some question as to whether the engine was warmed up fully. The water temp looked OK but the oil pressure was not down to the normal operating level. I've changed the exhaust system already and I have a few other things to look into. The next test will be by the seat-of-the-pants at Willow on the 23rd & 24th. Are you going to be there?
 

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Craig said:
G'Day Again,
I had never heard of an 'S' version either and I own one.

Apparently a TS with a cat, O2 sensor and a fuel vapour emission control system is a type 'S'.

And my TS was made in Nov 88 so whether or not a TS had an O2 sensor was based on where and when it was sold.
All TS cars had Cat and O2 sensor here in Sweden, I have only seen one TSpark S ever. :)
 

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I have a copy of a TS Manual Supplement I got from England (EB Spares) dated Jan 1987. I also have downloaded Craig's TS Manual Supplement which is dated Dec 1987. The cover of the English manual says "75 Twin Spark 2.0" rather than "75 Twin Spark S". The "S" manual wiring diagram for "Ignition and Injection, Motronic 4.1" shows M15 as a "Fuel vapour solenoid valve", S10 as a "Landa sensor", S25 as a "Connector for self diagnosis" and S30 as a "Map switching device connector". There is no mention of M15, S10, S25 or S30 in the "2.0" manual but there is a G49 labeled "Connector available" where the S25 and S30 leads terminate.

Now just to make it interesting, I also have some pages copied form an Italian TS manual (not dated but the same basic engine as above). The FI/Ign/Motronic circuit diagrams and pictorals in it make no mention of an O2/Lamda sensor but the text contains a long description of what one does, how it works and how to test it. It also has several drawing of the sensor. Still, I have two engines which I got from Italy and neither of them have Lamda sensors or evaporative emissions control connectors in their wiring harnesses. They also lack leads in their wiring harnesses for those devices.

Apparently Alfa made two TS engines, one with emission controls and one without. It would have been nice if they'd badged them consistently but it seems they didn't. Oh well ....
 

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G'Day Bruce,

Nope, one engine. S30 also has a link which tells the ECU whether or not a cat & O2 sensor is fitted.

I have bits of the TS Supp (in English) but am missing the page with the wiring diagram.

I also have a copy of the Italian version and page 73a ? SCHEMA ELETTRICO DI ACCENSIONE E DE INIEZIONE shows an O2 sensor (S10) bottom middle.

These manuals are not on my site as the are available from Maarten @ http://phantom.urbis.net.il/alfa75/technical2.html and because they are low res scans.
 

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TS Manuals/diags

Craig said:
G'Day Bruce,

Nope, one engine. S30 also has a link which tells the ECU whether or not a cat & O2 sensor is fitted.

I have bits of the TS Supp (in English) but am missing the page with the wiring diagram.

I also have a copy of the Italian version and page 73a ? SCHEMA ELETTRICO DI ACCENSIONE E DE INIEZIONE shows an O2 sensor (S10) bottom middle.

These manuals are not on my site as the are available from Maarten @ http://phantom.urbis.net.il/alfa75/technical2.html and because they are low res scans.
Craig,

Thanks. I have a good B size of the English diagram you appear to be missing. I'll scan it and email it to you. I also have a decent copy of a page 43 from an Italian manual (what I have is incomplete) with the title "ACCENSIONE INIEZIONE MOTRONIC MML4.1 (2.0 TS) (Schema A)" which does not have the O2 sensor (S10) but it does have S30 but with no description. It's a marginal copy but I can scan it as well. Can you contact me off line with an email address to use. Oh, I have a copy of Maarten's manuals and you're right about the resolution. However, I've seen a couple colour wiring diagrams in French that are much worse (BTW they show the O2 sensor).
 

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Bruce,

Thanks for the offer but I have several varieties of this diagram including a marginal copy of page 44 of the Italian supp (titled "ACCENSIONE INIEZIONE MOTRONIC MML4.1 (2.0 TS con convertitore catalitico) (Schema A) which does show S10 :)

You can contact me using the site feedback link on my site (see sig).

However if you ever scan the supp let me know or if you ever find some of the missing pages of the manuals on my site. (I must list whats missing)
 

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Well, I have the complete Direzione Assistenza Tecnica for more or less all the engines (75 TE and 3.0 P missing) in the 116/162b cars and it doesn't mention a TSpark S.
It's dated 1987 and has ****loads of updates.
 
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