Adding material to a port.

[4v6]

Good evening Guy, i hope youre well.

I have a question if i may regarding the addition of material to ports in an alloy head.

Is there any method besides welding that you have used or would recommend?

I ask, because during some tests of an Audi 20valve head (4 valves per cylinder), i had been probing the intake ports and i had found that adding material ( plasticine) to just prior of the short side radius ie, raising the floor slightly gave me a good gain in flow, both in bare port flow and valve in flow.
The ports had been pretty much unresponsive to most other modifications with a small gain in flow noticed by some minor ssr adjustments and cleaning up, with the biggest gain being the reduction of the guide bosses, nothing spectacular but i suppose a gains a gain.
Because of the position the material would need to be added, tig welding is pretty much impossible due to the restricted access.
Mig welding may be possible but by no means certain.
I cannot see any epoxy type material holding on year in year although i have made enquiries so apart from maybe some kind of soldering i think im probably stuck with the ports as they were cast.

Many thanks for any advice you may be able to offer on this question.

Best wishes, Tony.

[Guy Croft]

You can certainly use either Devcon or Loctite MetalSet (aluminium grade) with confidence, roughen the surface and clean with brake cleaner before applying. I have used both in the past on similar development work and from time to time on inlet manifold to correct or repair.

GC

[4v6]

Guy, I am indebted to you!

Many thanks for your suggestions, I shall purchase one of each product.

Best wishes, Tony.

[PersonaGrata]

Hi Guy,
I too need to use some kind of filler on my 4G93 head, and I was looking at 'Devcon' on an internet auction site. I need it to repair slight misalignments between valve seat and the throat. The depth of the fill will only be about 1mm max.

The only problem is that there are lots of different Devcon products and I am having trouble picking the correct one. I guess that an aluminium filled one is the one to go for - but I don't see that.

PS. I have some JB Weld in the garage, would that do instead?

Thanks
Iain McLean

[Guy Croft]

The Devcon product is aluminium putty type F, stock no. 10611 good for 121deg C

G

[PersonaGrata]

Many thanks again Guy