20v BT valves choice

izanagi24
Posts: 4
Joined: Fri Dec 18, 2015 4:33 pm

20v BT valves choice

Postby izanagi24 » Mon May 20, 2019 3:15 am

Hi everyone,
I'm doing a rebuild of my 20v BT.
My next step is to buy new valves.
As I already got TODA spring, what valves would you recommend with that valve spring ? Stock valves, Supertech valves (has been told they are noisy), Ferrea valves or other brand ??
I'm still running stock camshaft too.
Thanks for your help.

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oldeskewltoy
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Posts: 2180
Joined: Wed Jan 09, 2013 4:44 pm
Location: Portland, Oregon

Re: 20v BT valves choice

Postby oldeskewltoy » Mon May 20, 2019 8:02 am

izanagi24 wrote:Hi everyone,
I'm doing a rebuild of my 20v BT.
My next step is to buy new valves.
As I already got TODA spring, what valves would you recommend with that valve spring ? Stock valves, Supertech valves (has been told they are noisy), Ferrea valves or other brand ??
I'm still running stock camshaft too.
Thanks for your help.


same thing I answered @ aeu86.org.....

Why do you want new valves??

unless your plans include building this for substantially more power, stick with the OEM valves (known quality).
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

izanagi24
Posts: 4
Joined: Fri Dec 18, 2015 4:33 pm

Re: 20v BT valves choice

Postby izanagi24 » Tue May 21, 2019 12:37 am

oldeskewltoy wrote:
izanagi24 wrote:Hi everyone,
I'm doing a rebuild of my 20v BT.
My next step is to buy new valves.
As I already got TODA spring, what valves would you recommend with that valve spring ? Stock valves, Supertech valves (has been told they are noisy), Ferrea valves or other brand ??
I'm still running stock camshaft too.
Thanks for your help.


same thing I answered @ aeu86.org.....

Why do you want new valves??

unless your plans include building this for substantially more power, stick with the OEM valves (known quality).


Because after checking the size of the valve stem (according to the FSM), mine doesn't reach the size recommended. They are thinner.

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oldeskewltoy
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Posts: 2180
Joined: Wed Jan 09, 2013 4:44 pm
Location: Portland, Oregon

Re: 20v BT valves choice

Postby oldeskewltoy » Tue May 21, 2019 7:36 am

Stem and guide "work" together..... the same FSM lists maximum valve/guide clearance. I'd recommend using that before you condemn the valves.

Exhaust valve - 0.1mm (.0039")

Intake valve - 0.08mm (.0031")

If they still are too small..... the choice is yours... replacing OEM valves, with OEM can get pricey, or you go oversize with Supertech....

As to Supertech... OEM valves the intake stem is larger, but with the Supertech the exhaust stem is larger........ not sure why that is....
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!