RWD_cossie_wil

iTrader: (9)

Just wondering what dictates the maximum RPM of a YB? My guess would be in order

1) Std rod bolts
2) Hydraulic lifters
3) Con rods?
4) Valve construction?
5) oil pump?

What could you safly rev to if you replaced the con-rods with H section, std/std crank, solid lifters and cams etc, but kept std valves?

big_wig_074

the rev limiter?

RWD_cossie_wil

iTrader: (9)

Wouldn't expect a sensible answer off a fookin rigger

K-NINE

standard engine will rev to 7800rpm quite reliably,some have tried 8200rpm but has resulted in dropped valves.

StephTell

hey Phil, how are you these day's?

RWD_cossie_wil

iTrader: (9)

The valves are a two peice construction arn't they?

cossiedrift

iTrader: (3)

mine hasn't got a limiter and was revved to 7800 7900. standard rebuilt engine with wrc gasket

Benni

I really did have to look at that three times.

RWD_cossie_wil

iTrader: (9)

So any sensible answers?

K-NINE

1) Std rod bolts an issue past 7800rpm
2) Hydraulic lifters as above
3) Con rods? no issue upto 8200rpm imo
4) Valve construction? no issue i can see? (but you must use new exhaust valves)
5) oil pump? no issue really i'd think.

J1mbo

iTrader: (1)

oil pump is no prob but put the higher psi spring in

PGT

good response phil - lets see what you have to say when chip responds.........

RWD_cossie_wil

iTrader: (9)

I thought the valves were a 2 peice friction weld design? seen a few failures were the head has just popped off the stem, I assume due to the double springs/ high revs placing them under a lot of stress when they hit the seat?

K-NINE

exhaust valves are 2 piece yes,hence you must use new ones,then no probs.

RWD_cossie_wil

iTrader: (9)

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