EVO 1

[Gorilla]

Hallo,

I am after some Evo 1 information please.

Is the EVO 1 Head, exactly the same Casting
as the 2.5 16v 'Coscast' Head please ?

Or, are all the EVO Heads Mercedes own Head Casting ?

Is the Oil pump on the EVO 1 Chain driven as
the Evo 2 please ?
As the EVO 1 has a Duplex Timing Chain I am not sure how ?
Evo II is single Cam chain.

Are the EVO 1 Con Rods [154mm] long, Forged or Cast ?

Is anybody running 11.5.1 Compression Pistions
in there EVO 1 Engine please ?

Many thanks,

Reagrds,

Gorilla.

[JM Motorsport]

This is what i got from head, rest i need to check the workshop manual

not same casting as 2.5-16v
oil pump is not chain driven on evo 1
single cam chain

[Nagilum]

While the bore differes, the Heads are not exactly the same.
Evo1 still uses duplex-chain, just Evo2 has a single-chain again.
AFAIK most people driving STB are driving a C/R of 11.5+ (I think up to 13.0).

Regards
- Nagi

[Gorilla]

Hallo,

Mikael- many thanks for the info,
so just the Evo 2 is chain driven
oil pump, which given the space
on the Crank makes sense.

Nagi- thanks also, I know the 2.516v
will go to 96.5mm bore and that the
bore Diam on the Evo 1/11 starts at
97.3, but there is no water ways
between the bores on the Evo blocks.

Hence the 'centre to centre' on the bores
must be very similar on 2.516v and Evo ?

I would go 12.1 compression but much higher
then issues start to evolve unless you can
be sure of 99 ron Pump fuel.

Does the Evo 1 head have the larger stud
spacings for the Headers as well ?

Many thanks,

Regards,

The Gorilla.

[Gorilla]

Hallo,

Evo 1 std Pistons 97.3 bore @ 9-7-1 compression
Rod is 154mm with 51.7 Big end and 22mm Small end

Does anybody know the Piston Deck height please ?
''Das Kompressionshore mit Evo 1 Kolben bitte ?''

Evo 2 std Pistons 97.3 bore @ 10-5-1 compression

Does anybody know the Piston Deck Height please?
''Das Kompressionshore mit Evo 2 Kolben bitte ?''

Many thanks,

Regards,

Gorilla.

[16vau]

Hallo,

some pics from original Evo 1 pistons

Gruß Norbert

[Gorilla]

Hallo,

16vau- Danke fur das pics von Evo 1 Kolben.

Do you have any more pics with the measurements please ?

I still require some of the measurement information on the pistons.

Many thanks,

Regards,

Gorilla.

[16vau]

Bitteschön,

war mal fleissig und hab eine schöne Zeichnung gemacht

Gruß Norbert

[JM Motorsport]

Evo 1 pistons
total piston height: 59.9
from centre of rod to top of piston: 32.9
Dish diameter 84mm
weight 455g

Evo 2 pistons
total piston height: 59.9
from centre of rod to top of piston: 32.9
Dish diameter 76mm
Dish depth 2.4

[JM Motorsport]

Norbert war ein bisschen schneller

[Gorilla]

Hallo,

16vau & Mikael- das ist super, bitte.

Vielen Danke,

Gorilla.