altezza 3SGE cylinder head

[strx7]

can anyone tell me how much longer than a 3rd gen head a altezza twin vvti type head is?

[RomanV]

shorter overall given lack of distributor at the back, but longer by a small amount at the other end thanks to VVTI pulley. (But not as much as size of front cover would suggest, in terms of interference for transverse setup)

If you put non VVTI pulleys on it would be same difference at the cambelt end.

What are your plans, beams head on gen 3 block?

[Truenotch]

As above. The Beams head will fit on a Gen3 block but you need to drill one hole if you want the VVTi to work properly.

I've got an auto altezza head that I would part with fairly cheap if you want to have a play. I think one of the pulleys has been ripped apart though.

[strx7]

i'm toying with the idea of putting either a single vvti head or a twin vvti head onto my 5sgte bottom end.

What is the difference between the manual head and the auto head apart from the exhuast valves? slightly less cam duration/lift or what?

i'm thinking that vvti on the exhuast side would come in real handy for spooling the turbo earlier

[Distrb]

From memory i cant be sure if the casting is different but the Manual head has 6 cam caps on the inlet cam, where the auto has only 5. Buckets on the manual are larger (33mm vs 31mm) Valves on manual are titanium all round and larger (.5mm in; 1mm exh) Cams i believe to be different as well but i dont have specs to back that up sorry.

[Truenotch]

What's your compression going to be with the 5SGT setup? Beams heads have smaller combustion chambers so it will raise your compression a reasonable amount. I think 10:1 altezza turbo pistons work out at more like 9:1 in a normal 3SGTE, but haven't actually measured it.

From memory i cant be sure if the casting is different but the Manual head has 6 cam caps on the inlet cam, where the auto has only 5

Hmm, might have to go check that.

[strx7]

i did some calculations the other day and i'd need to change my pistons to something with more dish. otherwise i'd be in the 10:1 reigon, otherwise a 3mm headgasket would be in order

[matt dunn]

If I was to build another Turbo engine, 10:1 compression ratio is where I would aim for.
Better off boost response, better spool, and slightly less boost to make the same power, up to a boost level where sheer volume takes over.