Top end rattle

I've just purchased a 150k mile 1990 sx and would appreciate some advice on a few problems.
The engine rattles from the cams/tappets from tickover upwards.Can the tappets be adjusted or are they hydraulic?
The car runs out of puff about 5000rpm.I've fitted a boost gauge and boost peaks at 0.7 Bar and drops away slowly from about 5000 to the redline.Is the engine supposed to rev out?
The turbo seems fine mechanicaly and the car is not slow as it makes my 325i feel flat it's just the last 1400 revs when it dies.
Thanks.

[Matt_S]

Hi Cooky - welcome to the site!
Performnce wise, assuming ou have a standard T25 turbo fitted your car seems to be running OK. The small turbos normally push out 0.5 bar/7psi in standard tune, so it may feel quicker than it should!
The tappets are hydraulic and cannot be adjusted as far as I know.
Fairly easy to dignose and replace, but the cams have to come out I'm afraid.

HTH

Matt
V V tired now!

[Paul_Ralph]

Hi
I am just in the process of rebuilding a head at the moment and have found that the valve lifters can wear quite badly. These have to be removed and measured accurately (easily done with a magnet -- cams out)but once worn will rattle especially when the engine is warm. Hope this helps..!!!!

[Chimp]

/me starts to wonder if it is actually my top end thats rattling.

[Chimp]

ooh soz cookie forgot to actually post something that might help.

Boost will drop off as the revs rise with a standard T25, thats life im afraid. A combination of a useless intercooler and small compressor wheel and standard exhaust are enough to strangle the beast when it should be picking its feet up.

Some cynics might suggest a weak wastegate but I would walk into Macdonalds with me pants round me ankles if it was.

------------------
Dan
Red S13
Actuator/chip/filter
blue smoke, crunchy crank

[Kristian]

I agree totally. In standard form they run out of puff after about 5800rpm. not really worth revving past this. mine also put out 0.7 bar when standard and thern 0.9 with a hybrid turbo. now running 1-1.1 ish.


Originally posted by Chimp:
ooh soz cookie forgot to actually post something that might help.

Boost will drop off as the revs rise with a standard T25, thats life im afraid. A combination of a useless intercooler and small compressor wheel and standard exhaust are enough to strangle the beast when it should be picking its feet up.

Some cynics might suggest a weak wastegate but I would walk into Macdonalds with me pants round me ankles if it was.