Cam plugs - which ones?

[goldNSX]

The cam plugs are prone for leaking oil after some years.

Which ones would you choose and why:
- OEM rubber cam plugs. They tend to shrink over time.
- SoS billet cam plugs: https://www.scienceofspeed.com/inde...nts/scienceofspeed-billet-camshaft-plugs.html
- Yamamoto billet cam plugs: https://www.mitamotorsports.com/rfy/billet-cam They state to install them with liquid gasket like Hondabond.
- other

Other question: is it possible to remove/cur the OEM cam plug without lifting the head cover and to glue in a billet plug from only one side?

 

[Honcho]

If installed properly, the OEM rubber plugs should last until the next timing belt replacement cycle. Therefore, I always recommend them first. There are reports of the SOS plugs leaking due to the o-ring design. The RFY plugs are good to go, if installed correctly. I think they are overkill for what they do.

You need to lift the cam caps to get the OEM rubber plugs out. [MENTION=3729]Larry Bastanza[/MENTION] had a tool he rigged up for this purpose. The billet plugs may be able to be installed without lifting the caps.

 

[MotorMouth93]

I don't like the metal O-ring cam caps either, I'd either go OEM or RFY. On the engine in my car now I'm using OEM cam caps with a SMALL amount of Hondabond all the way around. On the sleeved 3.2L I'm building I'm debating between using RFY caps or machining my own metal caps that just push in from the outside using Hondabond as adhesive for easy assembly and serviceability. Metal caps and Hondabond should essentially last forever. (think oil pump flange, doesn't ever really leak)

 

[stuntman]

How are RFY billet caps different from SOS.

 

[MotorMouth93]

SOS caps have O rings, RFY caps do not and just seal using Hondabond all the way around. (Or whatever your favorite silicone gasket maker is)

You could probably remove the O rings from SOS caps and achieve a similar effect.

 

[goldNSX]

Thanks for all your responses.

 

[asylum]

There is also AS Motorsport that sell cam plugs without o-rings. Are they RFY ones ?

 

[goldNSX]

There is also AS Motorsport that sell cam plugs without o-rings. Are they RFY ones ?

Thanks for the hint. They have 3 rubber seals.

 

[stuntman]

SOS caps have O rings, RFY caps do not and just seal using Hondabond all the way around. (Or whatever your favorite silicone gasket maker is)

You could probably remove the O rings from SOS caps and achieve a similar effect.

RFY has deep grooves that look the same as SOS with the o-rings removed, no?

 

[goldNSX]

RFY has deep grooves that look the same as SOS with the o-rings removed, no?

You could be right about the grooves. Not sure if o-rings are fitted in them.

 

[asylum]

Concerning AS-Motorsport, the ones I ordered some months ago have 3 slits but no o-ring, despite the picture we find on their website show 3 o-rings.

 

[goldNSX]

Concerning AS-Motorsport, the ones I ordered some months ago have 3 slits but no o-ring, despite the picture we find on their website show 3 o-rings.

Are they supposed to be mounted with or without o-rings?

 

[MotorMouth93]

RFY has deep grooves that look the same as SOS with the o-rings removed, no?

The profile of the grooves is a lot different.

The SoS cam plugs have deep gooves with a square profile.

The RFY cam plugs have shallow half moon grooves as seen in this photo.



Sorry, no photos of the SoS grooves unfortunately, I sold those plugs on shortly after getting them.

 

[goldNSX]

The profile of the grooves is a lot different.

The SoS cam plugs have deep gooves with a square profile.

The RFY cam plugs have shallow half moon grooves as seen in this photo.

Have you already installed them?

 

[MotorMouth93]

I ran the RFY plugs in my built motor that failed. No issues with leaks for the 400 miles it ran before I tore it down again due to insane oil consumption.

I sold the SoS plugs due to a few reports of leaks, the fact that they did not fit well (lots of end to end play), and the fact that the directions called for oiling the O-rings before installation. Oil on the plugs and wet HB on the cam caps at the same time is a recipe for leaks in a spot that sucks to get at.

In my backup motor I have in the car now I have stock plastic/rubber plugs with Hondabond HT all the way around. No issues in 6k+ miles.

The first engine is getting turned into a sleeved all motor 3.2L and I'll probably use the RFY plugs in it again.

 

[asylum]

Are they supposed to be mounted with or without o-rings?

I received no o-rings with them.

The SoS are quiet different. They only have 2 slits with o-rings and the blind external face seems bigger than the inner one.