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Discussion Starter #1
Hi, I´m actually working in a TS engine which will go to my Spider, and want to share it with you.

The base engine is from a 155, and is needing a lot of work to make possible allocate it under the Spider bonnet.

The specs are the following (at least now):

- 155 block (cross drilled), head, and front cover.
- 75 TS crank and rods.
- 155 modified pistons: reshaped valve pockets, and coated skirt

The above combination will give a CR of 12:1 (fuel here is 98 RON)

- Reshaped intake and exhaust ports, valves and guides.
- Fabricated intake manifold.
- Individual roller throttle bodies.
- Fabricated stainless exhaust manifold
- Performance cams
- Programmable EMS

I hope to obtain around 200 HP @ no more than 6800 - 7000 rpm

This is an approach to the intake system:
 

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Discussion Starter #2
I have several TS engines to play with: two 155 TS (AR 67202), one and a half 164 TS (AR 06420), and one 75 TS (AR 06224), so my plan is to use components from one or another engine to obtain a "cheap" performance engine.

I have selected the block from the 155 because the oil jets under the pistons, and because it has a little more reinforcements seeming to be stronger than the 164 and 75 ones.

The block had an issue with two spun main bearings (#2 and #4) that ate a little material from the bearing housing, but as the rest of the block was in perfect conditions I decided to give it a opportunity filling with weld the worn surface, adjusting the caps, and line boring the main bearings gallery.
 

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Richard Jemison
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TS parts

- 155 block (cross drilled), head, and front cover.
- 75 TS crank and rods.
- 155 modified pistons: reshaped valve pockets, and coated skirt
The 155 crankshaft is the one to use. It is longer stroke than the 75 crank.
Using that crank with 75 (longer) rods with the 155 pistons will give far better CR ratio. Puts pistons 1mm farther into the combustion chamber.
 

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Discussion Starter #5
The 155 crankshaft is the one to use. It is longer stroke than the 75 crank.
Using that crank with 75 (longer) rods with the 155 pistons will give far better CR ratio. Puts pistons 1mm farther into the combustion chamber.
Alfa rods length (2 liter engines):

NORD: 157 mm
75 TS: 156.1 mm
155 TS: 153.1 mm

So using a 155 crank with NORD rods and 155 pistons will raise the piston 3.9 mm... too much. But using the 75 crank (0.75 mm less pin radius), with the 75 TS rods (3 mm longer) will raise the pistons 2.25 mm. It has been possible to allocate the pistons reshaping the piston head creating a squish band (which supposedly will increase the efficiency of the combustion chamber), and machining a little deeper valve pockets. the resulting CR is 12:1 (together with a little reshape of the combustion chamber)

As note aside, compression height of pistons:

75 TS: 33.75 mm
155 TS: 36 mm

Also 75 TS rod (and 164) seems to be stronger (and heavier) than the 155 one
 

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Discussion Starter #6
Nice work. What is the intake manifold made of?
Is made from aluminium, formed by two machined plates and four curved elbows obtained from an old intake manifold, everything welded together. The sealing against the head and barrel throttle bodies is by means of "O" rings.
 

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Looking interesting. Gets me exited about putting my Fresh TS in over the next week or two.

IMO: If I had a 155 crank and was buying new pistons, I would design some new pistons (85 mm) to get the comp and protrusions right, and have a 2042 cc engine. 70 cc's is not to be sneezed at...

Is there any other real benefits of a 155 head besides the absence of the inlet port entry bend? I assume the bump in the top of the port is still there? I have pondered this a bit... I don't have the equipment readily at hand these days, but I wonder if it is worth machining the ports of a 75 head and locktite-ing an interferance fit sleeve into them (done this a few times before). This would enable one to totally remove the hump in the roof of the port (where the oil drain is) and remove the bend. Make a custom inlet manifold and not have the issues with cooling plumbing from the back of the head.
 

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Discussion Starter #9
As I said before, I'm using the 155 block maintaining its front cover and oil pump, but as the engine have to go to a 105 chassis (Spider) it has to fitted with a 105 sump, and this has been a real PITA as can be seen in the attached pictures.

The reason to use the 155 front cover is that it (together with other tricks) enables to shorten the engine around 40 mm at the pulleys level, which will be good when redefining the engine bay in the radiator/fans area.
 

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Discussion Starter #10
Some more pics of the sump modification/adaptation, and from the 155 front cover and oil pump.
 

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I have a 155 head here in California for a future project. I want to follow this. I like the manifold, but I see the injectors are upstream a bit. Any reason why you didn't have the ports located where the injector cutouts in the head are? Is it a one-off manifold, or can more be made?
 

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Discussion Starter #13
The reason why the injectors are located a little upstream compared with the original configuration is to favor the mixture formation at medium/high engine speed.

In any case the injectors are pointing directly to the valve, and the barrel throttle opening is just under the injector tip (from top to down in the outlet side) helping to direct the fuel to the cylinder.

The injector cutouts in the cylinder head have been weld filled to avoid disturbance in the flow and waves propagation.

The barrel throttles have an internal diameter of 40mm, then the diameter is reduced progressively till 38mm at the manifold flange in the head, after, the internal diameter is approximately constant till the guide/seat area, where the diameter is 40mm approx. With these diameters the oil gallery bump simply could be eliminated, as will be seen in future pictures.

I suppose the absence of the angle in the inlet manifold flange is the reason of the better flow/performance of the 155 head, but when installing these engines in 105 chassis (and specially in spiders) is necessary to give some angle to the intake. In the 155 head the port is straight with an angle of 26º approx, further, the engine is tilt 4º to the exhaust side, all together means that if you want to maintain the throttles/trumpets in horizontal position, the ducts have to bend 30º, but in the fabricated manifold this is done with an ample bend.
 

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Hello, very interesting project. I have a 1970 Berlina and would also like to upgrade it to a TS engine. From the information contained, It sounds like you have done this before. I can see some advantages to using a 155 based engine. Do you know if there are any limitations that would affect the installation in a Berlina?
Thank you,
 

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Ts + s3

I think an S3 Spider with a TS and backdated bumpers would be an awesome car.
It really is. And it doesn´t need that many mods to achieve the same target like this thread describes. Many ways leading the same direction.
 

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Great project and very nice looking manifold, I'll be looking forward to the updates on this one.
 

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Discussion Starter #18
Probably there are a lot of cheaper or different ways to do the things, but I like to do the things my way, doesn't matter the effort, for me the satisfaction comes from doing the things, a very different thing is open your wallet and have a performance TS engine installed in your car.

On the build subjet again. Another care point is the engine height, TS engine is a little taller than the NORD, and this last is very tight with the bonnet, so any opportunity to reduce the height in the TS have to be explored.

The oil filler cap over the TS camshaft cover is the highest point in the engine, and despite many conversions maintain the cap in its original position without problems (as in the picture above), I prefer to change its position as can be seen in the following pictures.

I also have reduced some excess of material around the oil vapors connection.
 

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Nice work with the valve cover. I've contemplated a few mods to the cover too. I'd like to get rid of the ribs and make it smooth. Also to round off some of the corners to make it look a little more like a Nord cover.

I wonder if lowering the mounting of the cap would work, along with a flatter cap. Or say, a recessed mounting point for the cap.

By the way, if you still have the intake manifold for the 155 engines you acquired, I may need one in the future, so don't throw them away. That is, if you'd be interested in selling one day. I've been thinking of using the stock intake and welding mounting plates on them for throttle bodies.
 

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Discussion Starter #20
Barrel throttles are finished, the linkage have been a little like a nightmare but at the end it works perfectly, enabling the synchronization between bodies, and adjust the idle position (idle itself will be regulated by a Bosch idle controller). Each body has its own internal adjustable stop to set the full load position, and as can be seen the sealing against the intake "manifold" flange is with "O" rings.
 

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