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zetec black or silver top
APR - 2/11/05 at 08:28 PM

has any one used the 2.0l zetec black top and are these better for bhp than the silver top when using throttle bodies. any info on the up/down side of them

SeaBass - 2/11/05 at 08:46 PM

One downside of the blacktop is the you can't change the water pump to run the 'correct' way for a simple aux belt setup - you have to run serpentine and makeup an idler normally. Other than that don't know that much. I have a blacktop sitting at the mo gathering dust for use in the future. I've found the exhaust and inlet manifolds to be the same but others claim differences...

Cheers

stevebubs - 2/11/05 at 08:46 PM

Has been covered elsewhere

Primary differences that affect fitting are:
sump is 2 piece not 1
water pump goes the opposite way to the crank on *all* blacktop varieties

Blacktop is supposedly better for approx 10BHP in std trim due to the use of
solid lifters
teflon-lined pistons

There's also a bit more meat between the bores if you want to spend $$ on an custom build.

stevebubs - 2/11/05 at 08:51 PM

quote:
Originally posted by SeaBass
One downside of the blacktop is the you can't change the water pump to run the 'correct' way for a simple aux belt setup - you have to run serpentine and makeup an idler normally. Other than that don't know that much. I have a blacktop sitting at the mo gathering dust for use in the future. I've found the exhaust and inlet manifolds to be the same but others claim differences...

Cheers


I beg to differ on this.

My pump turns the right way, but it took some effort. There's a place in the US who makes water pump impellors that are a mirror image of the original. This sorts any cavitation issues with the centrifugal force.

You then just need to fit a suitable pulley. I got a local engineering place to make up an adapter plate to allow a pulley from a 1.8 silvertop to simply bolt up.

Alternatively, Westfield are now supposedly doing an idler pulley to maintain the belt pattern.

Details of both solutions Here

[Edited on 2/11/05 by stevebubs]

Big Stu - 2/11/05 at 10:39 PM

My solution was to mount the altenator facing the 'wrong' direction so that a normal pump can be used.

Sump is a two piece design which means it can be shorted easier.

Manifolds all seem to be the same.

APR - 2/11/05 at 10:56 PM

thanks for the advise. what bhp have people made from black tops

Big Stu - 3/11/05 at 02:22 AM

A two litre, with standard cams, decent ignition, and twin 45's should be good for about 160. You will get a little more with throttle bodies.

MikeRJ - 3/11/05 at 10:19 AM

quote:
Originally posted by stevebubs
I beg to differ on this.

My pump turns the right way, but it took some effort. There's a place in the US who makes water pump impellors that are a mirror image of the original. This sorts any cavitation issues with the centrifugal force.


Won't the pump housing be the wrong shape for the implellor though? I mean the outlet for a centrifugal pump would normaly be exiting in the direction of travel of the tips of the impellor. Having the outlet pointing "backwards" must surely reduce pump efficiency quite significantly?

stevebubs - 4/11/05 at 09:44 AM

In theory yes - efficiency is reduced. However it doesn't seem to be causing a problem - and I've had the car out on days where temperatures are 30+C without any problems.

If you want to go the whole hog, you can replace the mechanical water pump system with an electronic one for about £200.

S

zetec - 4/11/05 at 04:49 PM

I wouldn't worry about which to use. the big question for most people is the year it was made for SVA test.

If that is not an issue then the earlier engine seems better catered for for fitting into RWD cars. The sump on the earler engine is easier as it does not need to be chopped about to get the starter to fit.