Adding material to ports

[benlilly]

Hi Guy,

Probably not a very common question, but are there any readily available materials that can be used to build up ports and change their shape.

I had in mind Milliput (metal powder loaded epoxy putty) but don't know how it would react to fuel. Their website says it is useable up to 130 deg centigrade.

I ask because when looking at a spare (unmodified) Peugeot 205 8v head I have, it occured to me it wouldn't be too hard to make it more of a downdraft port by raising the port floor at the entrance whilst taking some material out of the roof to keep the area the same. Have you tried anything like this? I'll post a couple of photos tomorrow.

Thanks,
Ben

[Guy Croft]

I have used Devcon and Loctite Chemical Metal for flowbench and dyno development work but I would not tend to use actually in an engine port in case it shears off. Unlikely but not something I'd like to discover by accident.

I tried building up the 205GTi port much as you described on flow test - using Plasticine - to try and get the flow to go along the upper port section and off the floor, and it made it worse. So bad I didn't even photograph it, which I regret now!

I achieved huge flow with no valve by putting a particular shape of plastic deflector vane at the port entry (over 130cfm at 10") - but - it didn't work well at all with the valve in. I gave up in the end - you might do better - but bearing in mind that port - fully developed with the right cam - can push out over 170bhp at over 8000rpm, you have to ask yourself if it's likely on an 8V 1600.

GC

[benlilly]

Thanks for the info, Guy and given your experience, I think I'll give the experiment a miss.
Ben