Cylinder Head Improvements

[Zak33]

My mate here at work has just got a Bill Blydenstein head for his GTE (he's scared Im gonna catch him next season )

Now the work done involves changing the shape of the ports and other things that experienced builders of single brand engines know from hundreds of attempts....so it's hard for you too see them....

BUT...you can see what THESE DO with no real brain power at all. The head has slightly BIGGER valves AND the angle the valves sit inside each port effects the SIZE of the port too...

PLUS..to keep resistance to a bare minimum, the valves are "machined" thinner....its a balance of thin and strong....you gotta have good quality valves and know where too STOP GRINDING...but the combination is THIS.



RED shows theangle of the OLD VALVES SEAT...the biggest area of this valve is the narrow bit....the reason valves are like this is EASE OF PRODUCTION and the long term seat they make in the head...reliable.

The BLUE on the new valve on the right shows the steep angle....see howmuch BIGGER the area of the air flow will be...WIDER

Next...ytou cant miss the stems

HOW DIFFERENT is THAT? hehe

The air flows AROUND those......the airflow in through the SIDE and then DOWN around thevalves (they gointo the head upside down to the this pic)

THAT is tuning

[jon bda]

Waisted stems...nice as long as they are quality valves and the heads don't fall off...

[Lowe]

Good pic.

[[GSV]Trig]

If its an Astra GTE then it should be a coscast XE head, if its not slap him

[Mart]

Looks a bit like an exhaust valve from no3 cylinder on a vw flat four just before it drops

[RocketmanX]

Very nice Zak

Wise choice to improve the heads (as you already know ).
The valve looks very well designed. Steel or Titanium?
Best power option for any engine, with a well matched cam.

That is, aside from forcing extra air (turbo...) down it's throat.

Heads are big investment, but money well spent

[schrickvr6]

bill did the head on my jetta 16v a few years ago,very good workmanship and pretty cheap to

[[GSV]Trig]

Bill is a god tbh....

[IainB]

Hope he got a 3 angle cut on the seats

[Zak33]

Originally posted by Eazieb
Hope he got a 3 angle cut on the seats

He hasn't actually.....triple angle valve seats are nice, but this caraint high enough state of tune/compression etc for that.

Its on a STANDARD cam at the mo...and it has made a good difference....

Bill IS a god...I agree.....he did my Dad's Viva 2.3 Magnum when I was 8 years old....now THATS a long time ago.

Trig....its a Nova GTE mate...1.6. Its why I took the photos...same head as my Astra rally car.....now I know exactly what it looks like

[IainB]

Originally posted by Zak33
He hasn't actually.....triple angle valve seats are nice, but this caraint high enough state of tune/compression etc for that.

Its on a STANDARD cam at the mo...and it has made a good difference....

Really - quite suprised at that - would have thought that was part and parcel of having the work done on a head - especially if your going to the length of changing valves to complement port work, would have thought waisted valves and a 3 angle seat would have gone hand in hand?
Did he have the seats re-cut for the new valves - or lapped them onto the old ones?
(just curious as to how other machine shops work )

[Zak33]

Seats were recut......but defo not triple angle...looked for that.

Tell ya whathe has done....ground away the edges of the valves stem seats...on theinlet side....they are kind of.....smoothed off.

The head shape is different, around the inlet valve, the area behind it is slightly larger, but its minimal. I'll try to get pics for ya...I have them but pointing out the difference is really hard.

Gimme a moment....I only have PAINT on my work PC

[Zak33]

cants get a proper piccie.....no good

soz