recently i have upgraded some stuffs (eg. cam, clutch, flywheel, final drive, air filter) to my cooper S, i was planning to do head and valve (just upper part). the shop tells me to replace the piston, retainner and other valve also due to worn out or loose and overheat.

anyone can tell me if normally changing cam need to replace them? with new cam, can i still use stock connecting rod, valve etc?

also he says my spark plug looks 'white/dry', maybe not enough fuel. my friend said the ecu maybe amended while the shop says no. say the spark plug has no problem, do i need to upgrade ecu for new cam?

sorry to ask many questions, im just a new mini fan (daily street driver). much appreciated.

 

How many miles you have on the car? I'm wondering why would they be worn out so soon unless the car was abused.

The head could have been replaced when the cam was being put in. Anyways, the heads most have very good experince with recently has been the RMW of Revolution Mini I'm sure others such as Fireballed people and Thumper heads are good as well.

 

when the shop tested the car with new cam and new spark plug, he said the spark plug is 'white' on the tip after run. so he suggests to upgrade the ECU to give more fuel. i'm not sure if he's just spoofing.

also pls see my head. anything wrong with it? they said i need to replace piston, connecting rod, valve springs, retainer etc. almost everything needs to be replaced. very $$$$$$$

 

[IMG]file:///C:/Documents%20and%20Settings/jayp/My%20Documents/dsc08422.jpg[/IMG]

 

Your bottom end looks fine....you can see it runs rich by just looking at the pistons. Dont go by reading the plugs, I can pull my plugs and they will look the same as yours, but I monitor my A/F ratios with a wideband o2 gauge. If you dont want to install one, just run it on a dyno that can read your a/f ratios & rest well.

As for the head, I would buy one complete from someone reputable in the MINI buis. I went with RMW for my head needs.

 

i went down to the shop last night. the guy claims the valve springs are a bit loose/worn out. also he can rotate the pistons a little bit (maybe 1.5mm by the look). to me, quite sensible for a 4 yrs car.

i think i may replace all valves, retainers, pistons etc with stock just for peace of mind. personally i don't think i need racing kits. a ported head may just do the job well...

 

Jayk,

before making any costly and possibly unnesessary changes to the engine check with a shop that deals specificly with the mini cooper engine. unless that is the case.

dan

 

If you are going to do all of this, you might as well go up in valve size (+1 or +2 valves). You should price out a RMW head, wergner head, Thumper, ect.....

The cost differencial might not be much and you will get more.

 

+1

 

but that said, the issues on wear can't really be seen by eye, and can only be know for sure by measuring the parts.

All supercharged MCSs run rich. They use extra gas to cool the chamber. But I think you'll find stock replacements ususally cost more than performance parts!

Matt

 

Roger the head exchange.!!.. look at the cost of the head repair.. then the cost of a port head bolt on ready, some times the ported head is actually CHEAPER, or with in just a few more dollars!! Just a thought, the labor to R&R will/should be the same... yes!!
Just a thought...

Just me...............................................

Thumper