ASHCOSSIE

bronze seem to be about £100 for the set while steel are about £40, is there much of a difference
these r the steel ones http://www.ebay.co.uk/itm/Ford-Coswo...1#ht_944wt_950
these the bronze ones http://www.mattlewismotorsportonline...?productid=208

fezzajsy

iTrader: (9)

would luv to know too as my cylinderhead is going for a makeover

martysmartie

iTrader: (1)

As you may know the standand material is useless, hence why they eat guides!

I always remember Tabetha saying to use Colshubo (sp).

Martin

Brendan

iTrader: (1)

Bronze valve guides are better , I had mine turned from a bronze alloy called trojan, they were also setup so the water jacket could cool them further! Hell! I was working in the city at the time and could afford it then! The engine NEVER runs hot not even did a lap of the TT once with no fan and was fine while keeping up with a new 325. in a 18 year old fiesta RST. So if you can afford it go for the beryllium copper bronze otherwise TROJAN. Should you want to work out about converting to water cooled too that is more money again but bloody effective, ford patented a version of this in one of its old formula 1 engines. – ring me and I will put you in touch with the guy that did it for me.

I also recommend HOT honing if you are going that far…. You heat the block up to working temp then hone the bores, this way you know they are right when the engine is up to temp….

dug112y

iTrader: (1)

if your getting it done use colisbro.

bredan, tell me more on the HOT honing front.

Brendan

iTrader: (1)

ok, to do this you need the block at at running temp this will depend on your thermostat setting, to do this you have to heat it up by running hot water through it, we took a feed from a central heating system! Then I had some adapters made up so water can be run through the block. Then off you go! It is bloody hard and hot work.

my friends think I am insane - as it was only a CVH but it is my baby!

dug112y

iTrader: (1)

what about the piston temp?

RS SHAUN

iTrader: (24)

Were do you get colisbro guides from?
Cheers shaun

Brendan

iTrader: (1)

I realy wold recomend trojan ones, as regarding pistons not in the block when this was done!

dug112y

iTrader: (1)

obviously, but how do you get the right clearance? iron and alloy dont expand at the same rate so do you heat the pistons to the same temp as the block then measure them to get your clearance?

dug112y

iTrader: (1)

arrow or andrews precision or ttv racing would be a good start for colisbro.
ca104 and colspeed 90 are other good valve guide materials.
manganese bronze is shite and what alot of them are made from ,do not use it.

RS SHAUN

iTrader: (24)

Cheers mate

Brendan

iTrader: (1)

If I remember correctly we asked JE (I had them make some custom ones for me). Then they were sent them off to coventry balancing along with most of the other moving parts in the engine. Dean (my engine builder) managed to get the bores to about 1/2 a thou of an inch to their spec. - I told him he was lucky, he said no just showing off! That bet cost me extra whisky any way!

TimC

iTrader: (1)

Did you use a torque plate when measuring and honing the bores also? Amazing how much a block can twist when it has a head on it and is torqued up.

Brendan

iTrader: (1)

Yes we had to! the torque plate was also formed to be the top part of the adapter for water into the engine block for heating it up! our one was made from ally four holes cut in a bit bigger then the pistons then some holes cut for the water to heat the block!

dug112y

iTrader: (1)

your engine builder will measure the piston then hone bore to suit. JE quoted clearance will be cold/room temp i guess . so how do you get a hot clearance to hone to is what i am asking.

Brendan

iTrader: (1)

I will have to ask Dean to be 100% sure. But I think we asked JE for spec at working temp and checked out that the piston rings cold cope when it was cold.

I also should say that I normally start it after heating the sump with a radient heater for 20 to 30 mins so the oil is hot from the off!

dug112y

iTrader: (1)

SERIOUSLY?? not really practical for a road car is it. You got any photos,it must be a bit special.

Brendan

iTrader: (1)

yes, I have.... give me till tomoz and I will dig them out.....

btw I do use it as a road car normally that's what they were meant for not locking away all the time, she need a bit doing at the moment, service, brakes need bleeding and the oil return onthe turbo is leaking a very little so will be busy when I can find the time away from my work, wife and Little one!

Brendan

iTrader: (1)

this is what we did! to hot hone my cvh!

jamie956

Burton power £6.30 each.