TwinSpark engine upgrade paths

Plan A (race type high-compression)
http://catcams.co.uk/acatalog/Alfa_Romeo_75___164_2.0L_Twin_Spark.html
http://www.pipercams.co.uk/pipercams/www/product.php?pid=AR20BP300
http://www.cb-cams.com/catalogo_auto.php?lang=ita&sel_id_marca=1

CR 11.3:1 - 12.:1
Venolia, JE, ASSO, Ross, Jahns, Accralite, BRC, CPS pistons


Plan B (mild street engine with mostly stock parts)

Using NORD rods (1mm longer than 75 ones), the protrusion of the edge of the piston to the block deck will be 0.25mm, so it's needed to chamfer slightly the top of the piston, and this will give you 11:1 CR, being also needed to deep a little the valve pockets on the piston, no worries, 75 TS piston crown is 1mm thicker than the 155 one, so you have enough material.

 FMG_V6_btb thread (roller throttles thread)

Stock parts performace TS discussion



Plan C (mild turbo)

GT2560R specs


Sources:
- 200HP TS engine (spider) | ITB thread
- TS with Nord rods
- GTV with modded TS
- Cam designs and performance
- TS with MS and ITB's on Alfabb
- Spider TS conversion
- Suzuki GSXR ITB's on a swift engine
- GSXR throttle bodies on Toyota engine
- Nord with GSXR 750 ITB's
- Mikuni's on 2l (87% diameter venturi for intake valve diam.)
- Spider with mikuni's
- R1 mikunis on a Toyota
- R1 carbs x-flow (fuel pressure important)
- Turbo TS discussion @ Alfabb (Mende with imsa too)
- Cheap TSTurbo @ alfapower.nu
- Flying miata turbo kit (with GT2560R, 250hp from stock internals)
- My topic at AlfaBB
- Cam discussions with Richard Jemison (Nord engine)
- Cam timing (Richard Jemison), early/late VVT
- TS intake options | shopping list for conversion (Nord to TS)

Alfa 155 1.8TS Sport, AR67102, 167A4C

Tensioning the chain:

This is how I do it, set the crank at tdc, turn exhaust cam clockwise and connect chain, rotate exhaust cam anti clockwise to take up slack from intermediate gear to exhaust cam. rotate intake cam clockwise to get slack inbetween cams, connect master link, rotate intake cam clockwise to take up slack. This way the only slack in the chain is between the intermediate sprocket, tensioner, and intake cam. This is taken up by loosening the tensioner bolt on the front of the head. It will snap out and take up all the slack, tighten bolt. If the cam timing is set right the marks on the cams and #'s 1 and 6 cam caps will line up. Hope that helps.