alexpulsar

[alexpulsar]

got a few problems to start off with when i leather my gti R approx just before 3rd gear runs out it cuts out for a second or 2 ??? i have blown fuses for fuel pump i also run a walbro 255 pump.it is a brand new race built engine which has covered 1500 miles.the oil pump is a new 1 but sometimes the oil pressure gauge just drops to 0 on tick over but dab the revs and it goes straight to about 3 bar under load and general cruising the pressure is great.pressure relief valve sticking maybe ???? finaly i am using wossner forged pistons and from cold it sounds like a diesel and when it gets hot it is still there but very faint im aware of the piston to bore clearence with forged pistons so the question is has anyone else had these pistons and do u get the same problems with wossoner pistons. i know hks and je go totally silent woul love to know :roll: :roll:

 

[EssexAaron]

whats our oil pressure on start up, mine sits i titch over 6bar..

and when driving around 4-5bar

idle 3bar

 

[alexpulsar]

from cold tad over 4 bar then hot idles at 3bar 4bar under load but have had the little dials apart to fit white dials .but that dont explain oil light coming on and pressure dropping on tick over dont always do it though ??

 

[stedee]

i had similar problems and i changed the sender unit - cost about 90 quid and all was ok, now my r reads over 2 at warm idle and 4 at 3000 revs
btw nissan say it should read between 3.5 and 4.5 at 3000 revs.

 

[turbodaily]

oil pressure could just be down to a faulty oil pressure switch. would try changing that first.

forged pistons will slap abit when cold, some brands worse than others, but should quiten down once they've expanded and at normal running temp.

who built your engine? and do you know what tolerance they used for the piston to bore clearance? as they recomend you run with quite a large clearance if the engine is going to be driven hard on track and running a fair amount of boost,to compensate for piston expansion. only down side is they can be noisy even at normal running temps,but obviously that wouldnt be an issue if the car was only used on track..

 

[alexpulsar]

im using the car as normal road use not track not sure of clearences engine was built by toovy road and race cannock staffs. car goes well just sounds dicky if u listen to it carefully.

 

[rx jamie]

try make sure you change the oil regular mate. mine sounded similar before the bottom end went, which was mainly down to my stupidity.

 

[pulsarboby]

tbh alex i dont like the sound of what you have described!
first of all, 15000 is hardly a new engine in performance terms.
problem could possibly be a faulty oil pressure sender unit but it could be that you have no oil pressure!!!
i would change the sender unit immediately before driving it any further and risk causing irrepairable damage to your crank and possibly the block 'should an end cap let go'

some forged pistons are noisy from cold but then the noise your hearing could be a big end knock before oil pressure builds up!
you really need to get this sorted asap.

i have known good oil pressure senders should you want one (and no im not trying to frighten you so i can flog one):lol:

 

[snoon]

I have Wossner forged pistons and mine do quieten down a bit once warm but too much, but to be fair mine has always been a fairly noisey engine anyway, even when it had the standard pistons.