Which valve guides?

[sprint]

The valve guides on my A4 need replacing. It still has the original phosphor bronze guides, which were prone to premature wear, question is which are the best replacements?

Are the APE guides OK? Being phosphor Bronze themself are they any better than the original ones or is it better to replace them with cast iron ones, as Kawasaki later changed to?

Don't plan to use genuine Kawasaki ones as they are too expensive.

Original valves and springs are all still OK.

[Z1parR]

I did a head last summer and bought these fron zpower .
Don't forget to buy the circlips too .

https://www.z-power.co.uk/merchantmanag ... ts_id=1307

[sprint]

Thanks for the reply.

These look to be the cast iron versions? Circlips look to be included.

Did you remove the old guides and fit the new ones yourself? If so did you drift the new ones in or have them pressed in?

Did you then have to ream the guides and have the seats cut or were you able to just grind the valves in?

Anybody used the APE ones?

[Z1parR]

Those in the link i bought from zpower , they didn't come with circlips as i found out .
After drilling through the old guides with progressivley larger drill bits .
With plenty of heat from a torch i knocked the guides out with an ally drift .
Then knocked the cooled new guides in immediately after .
You will have to run a 7mm reamer through the guide before lightly re cutting the seats .
If you manage to align the new guide with the existing seat then it will be a fluke .
Then just lap the valves to the seats as per normal clean up .

[ZedHead]

http://www.saisei-europe.com/Shop/Produ ... lve-guides

[Z1parR]

Good to see you're back with us Dave

It is still Dave isn't it after your rather delicate removal operation

[zed1015]

APE bronze guides are good.
The early Kwak bronze guides were made of inferior alloys which is why they wore out quick.

[ZedHead]

Good to see you're back with us Dave

It is still Dave isn't it after your rather delicate removal operation

Thanks Geoff, just goes to prove you don't know what is around the corner.

As far as i know i am still Dave

[sprint]

http://www.saisei-europe.com/Shop/Products/c/engine/p/valve-guides

I note that APE guides are claimed to sit lower in the head for use with high lift cams:

APE guides are precision machined with the bores finished to size.
They are designed to fit lower in the head to clear high lift cams, and use APE seals or factory OEM seals. Sold in sets of 8

Does that mean they are shorter and therefore, have less support for the valves?

Also the ends of the guides don't look like they will like being drifted in?

http://www.saisei-europe.com/Shop/Produ ... lve-guides

Anybody had any direct experience of the APE guides?

[sprint]

Those in the link i bought from zpower , they didn't come with circlips as i found out .
After drilling through the old guides with progressivley larger drill bits .
With plenty of heat from a torch i knocked the guides out with an ally drift .
Then knocked the cooled new guides in immediately after .
You will have to run a 7mm reamer through the guide before lightly re cutting the seats .
If you manage to align the new guide with the existing seat then it will be a fluke .
Then just lap the valves to the seats as per normal clean up .

Thanks for the replies.

With respect to reaming after fitting, can you ream the cast iron guides by hand?

[zed1015]

http://www.saisei-europe.com/Shop/Products/c/engine/p/valve-guides

I note that APE guides are claimed to sit lower in the head for use with high lift cams:

APE guides are precision machined with the bores finished to size.
They are designed to fit lower in the head to clear high lift cams, and use APE seals or factory OEM seals. Sold in sets of 8

Does that mean they are shorter and therefore, have less support for the valves?

Also the ends of the guides don't look like they will like being drifted in?

http://www.saisei-europe.com/Shop/Produ ... lve-guides
Anybody had any direct experience of the APE guides?

The APE guides are only slightly shorter on the cam side so do not have less support for the valve and there is no difference between these and any other guide as regards to fitment and drifting.
The APE guides are actually better that the OEM guides as they use a shoulder rather than a circlip to set their height in the head.
With the circlip it is possible for the guide to be pressed too far into the head by an inexperienced or heavy handed mechanic.
I have fitted hundreds of APE guides amongst others.
You may still need to ream and hone the guides despite what they claim.

[zed1015]

With respect to reaming after fitting, can you ream the cast iron guides by hand?

YES.

[sprint]

With respect to reaming after fitting, can you ream the cast iron guides by hand?

YES.

Thanks.

Do you use the same 7.0 mm reamer for the cast iron guides as you do for the Phos/Bronze ones?

Which reamer is best to use, straight or twisted flutes or does it not matter?

[zed1015]

With respect to reaming after fitting, can you ream the cast iron guides by hand?

YES.

Thanks.

Do you use the same 7.0 mm reamer for the cast iron guides as you do for the Phos/Bronze ones?

Which reamer is best to use, straight or twisted flutes or does it not matter?

I use twisted flute reamers as they are more accurate and have used the same reamers for both bronze and cast iron.
When using the reamer only rotate it in the direction of cut or you can blunt it.
You will need a guide hone to finish to size after reaming.

[sprint]

With respect to reaming after fitting, can you ream the cast iron guides by hand?

YES.

Thanks.

Do you use the same 7.0 mm reamer for the cast iron guides as you do for the Phos/Bronze ones?

Which reamer is best to use, straight or twisted flutes or does it not matter?

I use twisted flute reamers as they are more accurate and have used the same reamers for both bronze and cast iron.
When using the reamer only rotate it in the direction of cut or you can blunt it.
You will need a guide hone to finish to size after reaming.

Thanks for the reply. Is the correct reamer with the cast iron guides 7.00mm?

Have not heard the need to then hone the guide afterwards, is it necessary?