The good bit is that on the 75 the main flywheel (the one on the engine)=20 serves for nothing else than carrier of the starter crown and fixing=20 plate of the first rubber donut. It is easy to get to from under the car=20 (but you need a lift)
Those rubber donuts on ANY 75 need checking regulary. They age and=20 crack. If cracked they have to be replaced, they are not cheap. Been in=20 a red light race with a Saab when a donut snapped, didn't like it.
Which aint the case: Alfa even specified that the twin clutches on the=20 GTV6 and the 75V6 could be replaced by the single plate clutch of the 75=20 TS. This directif came after all dealers replaced the twin clutches by=20 the single TS-one as standard...
As to the AR75TS gearbox: they are so fragile that the gearbox in the SZ=20 is... the same. They only complaint I have -and that is with every car=20 of that era the same- is that the throw is very long.=20
Shortshifts exist but are actually slower unless the gears are=20 lightened. Shortshifters needed a lot of force and abused the synchros a=20 lot. Lightening the gears makes the synchro's life easier, speeds up=20 gearchanges by about .2 sec and increase their life span 5 fold.
On the downside: a lot of work and not worth doing on a streetcar. It is=20 possible without a CNC-milling machine but it is time consuming. CNC- milling and several boxes to do means however a healty profit.
=20
Out of memory: porting (8 valve block) and 1 mm bigger inlet valves 800=20 Eur (valves included), shaving 0.5mm of the head 100 Eur. Supersprint=20 exhaust (300 Eur, weight gain 5 kg), inletcollector (ex-Formule 3 I=20 believe) free: received it as a gift, super chip with RPM max at 7200:=20
200 Eur.Extra cost: metal head gasket (in AR racing list) 75 Eur and putting it=20 together which I did myself. 180 HP @ 6900 RPM AT the wheels which is=20 about 210 HP flywheel or 60 HP up from standard.
60 *real* HP for 1400 Eur is -in my book- great value for money when it=20 concerns a NA-engine. To put in perspectif: a NA Porsche engine which=20 goes from 350 HP to 640 HP is invoiced 25000 Eur(of which 5000 Eur is=20 fitting).This means -in my world- that 60 Alfa HP costs a third of 60 Porsche HP.
State of tune of the AR-2liter =3D 210 HP/ 2 liter =3D 105 HP/l State of tune of the Porsche engine =3D 640 HP / 6.9l =3D 93 HP/l
You mentionned cost versus gain?
Both of which are illegal here (tuning the NA-engine is too but as long=20 as they do not see it, you walk free).
I don't underestimate the Belgian MOT-inspectors to the point that they=20 wouldn't notice a 6 potter from a 4-pot nor that they wouldn't recognise=20 a turbo.
The V6-engine (about 60 kg heavier than the TS) in the 75 makes the car=20 very noose-heavy which ment that my 75 TS (=B1210HP) was 5 seconds a lap=20 faster at Spa compared to a 75 V6 who claimed 260 HP...
Those 260 HP are verified : he overtook me above the Raidillion but=20 after the straight I sailed through without any problem and I never saw=20 him again.
Tom De Moor