Karlos G

iTrader: (4)

Have been thinking about fitting one as the standard ones, and so called high pressure ones are shite when compared to other engines!

To elaborate... a CVH oil pump will hold around 40psi @ 120degree's @ 3000rpm on a good engine, where as a Zetec will hold around 80psi!!
Seeing as our cams wear away at an astounding rate (even the Newmans), and this is primarily down to poor lubrication the higher I can keep my oil pressure the better!

Any thoughts, anyone done it before?

Cheers!

xr2wishy

iTrader: (2)

you've got a couple of options, either go zvh with a 1.8 bottom end and skimmed pistons, you'll be fine till about 250 bhp and will give you good oil pressure:cost saving option
you could go for a dry sump setup, expensive, but you'll never suffer oil pressur eissues, although take up more space:expensive option.

or you could fit an accusump, which will help with oil surges and maintain at least the idle pressure at all times.

jonny s2

iTrader: (12)

NMS modify the rst oil pump,never really heard of there engines failing

Rick

Nothing wrong with the CVH oil pump. More oil pressure will not stop the cam wearing, ithis is due to the design of the cylinder head that no 8 lifter doesn't get much oil directed to it, and the very heavy valve train uses high poundage springs.

You can easily increase the oil pressure by packing out the pressure release spring if you want - but this is normally only done if you have added an extra oil cooler.

The pump can priduce 100's of pounds of pressure, but a releif valve stops it doing so, and blowing itself to bits. High oil pressure will blow seals and cost you power. The engine was designed to operate at around the 40psi mark. Oil flow is what stops things wearing, not pressure.

Rick

The Cosworth DFV revs to 11k+ and peaks at under 40psi as an example.

rstdave

iTrader: (3)

What do nms do to the oil pumps bar packing out the relief spring, anyone know?? Although my oil pressure has never seemed as good as i'd like it never actually seems to cause a problem, bearings were fine on the engine i had let go even though it had rubbish oil pressure when it was 90-100 degrees on track and according to the gauge suffered surge through some bends.

Karlos G

iTrader: (4)

Yeah thats very true......
Cold pressure is irrelavent it's what you hold when the oil is hot, drive fairly hard for 20-30mins then see what it is @ 3000rpm should be around 45psi, and idle should be around 15psi

They fit a custom high pressure spring............. it was Karl I was talking to that made me think about increasing the oil pressure, as he pointed out how crap it was compared to a Zetec for example
Also with a leccy pump you can have it prime/run before the engine starts (reducing wear) and run after the engine shuts off meaning you dont have to wait for the turbo to cool down!

crazycage

just sell up and build a zetec turbo easy 300hp and will last forever

Karlos G

iTrader: (4)

lol That is actually a really good idea!!!!

crazycage

theres nothing to it mate. more power less lag better reliability

jonny s2

iTrader: (12)

lol thought you were a cvh guy,lol, run lower boost more power and reliable with the zetec

Karlos G

iTrader: (4)

Well I am but you cant help but admit the faults of the ageing CVH, and that fact that a couple of the big name tuners are pulling out of setting up/building CVH's nowadays, even the blocks/heads are giving up and cracking far too regularly from what i've been told, alright for sub 200bhp builds but over that they are a ticking time bomb
Obviously dependant on how many miles the block/head has done over it's life time, but trying to find a low mileage one is nigh on impossible!

Chris69

Just go Zetec turbo then- if i ever want an rst with a reliable 250+bhp thats wot i would do.
the cvh is a good engine but after 250bhp there really are a lot of restrictions to work around

mk1trb

sorry about the hijack but how do you do this then?

Rick

there is a torx head screw on the rear side of the pump. Undo this, and place a washer/spacer between the spring and screw. Start with a couple of mm, and check the oil pressure. The more spacers/more spring pressure, the longer the releif valve will stay closed.

My last CVH didn't have this touched, and after 40k and around 300hp, 7400rpm the crank and bearings looked new - that ran 45psi. Pity the valve shit itself.

Rick

Chip

iTrader: (3)

Sod trusting an electric oil pump for long term use on a road car, far more likely to go wrong than a mechanical one IMHO!

mk1trb

any pics of where the screw is lol

Karlos G

iTrader: (4)

It was just a thought, but after some more thinking................. probably a big waste of time! lol