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cylinder head


jagman

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OK, time to clear a few things up:

 

1. I was not and had not used Iridium plugs for some time.

 

2. The damaged piston / cylinder that looks loads cleaner was as black as the others when first exposed. Adam cleaned this up so that it could be seen properly when photographed.

 

So, it was not a single injector at fault here.

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wasnt the fpr then?

 

The FPR incident occured before the valve finally gave way. At the time of the FPR incident, I blew number 6 plug completely. We all thought I had been very lucky not to have caused damage to the valves, cylinder/piston or turbo and thanked a higher being for such luck!Unfortunately, about 1 month or so later, I had been out doing some "spirited" driving when the car developed a serious misfire. We have now seen what that problem was.

 

Now, before people start posting up defences and counter arguments, I am not saying that the FPR issue caused the latest valve problem. I am just pointing out the series of events.

 

When Adam posted this thread he did so to show everyone what problems had occured and to show what steps were being taken to rectify these and to strengthen the engine etc. He did not post to apportion blame or to slander anyones products etc.

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OK, time to clear a few things up:

 

1. I was not and had not used Iridium plugs for some time.

 

CJ , what type of plug actually broke? What was the heat spec? was it the tip or porcelain? Do you still have it or pic?

 

Regards, Charlie.

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CJ , what type of plug actually broke? What was the heat spec? was it the tip or porcelain? Do you still have it or pic?

 

Regards, Charlie.

 

1. It was a NKG plug.

2. Not sure what you mean by heat spec :conf:

3. Both tip and porcelain

4. No and no

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Quick question CJ ..Not really related to this thread . Have you still got the Plugs that Guy at CPL put in and what ever happened to them ? Were they the HKS ones ?

I took those out and put in NKG after hearing of the problems with them and det etc. I might still have them in my stash somewhere. Why? Wanna buy 'em? :p

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Phew ..thank christ for that. Just worried that you was still using them that all.

Nope - I remember leaving there and a few weeks later talking to dude or Terry (cant remember which) and them reccomending changing them for the NKG.

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Guest Terry S

Mate if the car is tune well the IK's are fine. They dont like bad DET. The ceramic cracks. The NGKs seem to lose there tips instead. Sheady uses IK's on the 40 psi Cossies, and has never lost a plug apparently.

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Mate if the car is tune well the IK's are fine. They dont like bad DET. The ceramic cracks. The NGKs seem to lose there tips instead. Sheady uses IK's on the 40 psi Cossies, and has never lost a plug apparently.

 

Wouldn't it be a good idea to not actually have det rather than fit sparkplugs that disintegrate in a friendlier fashion? :blink:

 

-Ian

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Guest Terry S
Wouldn't it be a good idea to not actually have det rather than fit sparkplugs that disintegrate in a friendlier fashion? :blink:

 

-Ian

 

Absolutely

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Guest Terry S

We have a set on the shelf next to the chocolate ones ;)

 

If you are serious there are some proper titanium ones, circa £3000 a set.

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We have a set on the shelf next to the chocolate ones ;)

 

If you are serious there are some proper titanium ones, circa £3000 a set.

LOL, I thought that aluminium sounded iffy but had read about them on SP and was offered some very cheaply.

 

£3000 :eek: I could buy a house in Wales for that sort of money :p

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anyway-back to the head, having taken the head to my mate to have a look at what he can do-firstly he thinks the original head is of a superior design as stock(common with most jap cars)but improvements can be made-there will be less gains with stock turbos as the head probably equals or out flows their capeability,with uprated turbos/turbo more gains will be apparent,in a single set up it will also drop the rpm that it will hit full boost/speed up spool time due to increased flow thru the head. there are very few gains to be had from from inlets but a slight polish deep in the tracts will help,the chamber polish will also not provide a huge gain but every little helps-the main gains are to be had in the exhaust ports-but as you enlarge these air volume increases but the velocity decreases this is where a seriously good head guy earns his crust by enlarging the port and altering the converging duct then polishing every surface within the port and matching to gasket/manifold about 2-3 days work by hand and all done by experience-too much off = nackered head

not funny on a megabuck race engine. its all down to the guy having nearly 30 years doing nothing but porting-having done 1000,s of heads and all the feedback from the race teams ie what lasts /fails/etc. the 2 heads he has mine and cj,s both have oversize valves and he thinks he can achieve 10% increase in torque throughout the rev range and its associated bhp increase

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