Unusual cylinder head mod!

[360gts]

I picked up quite a nice 1805 head recently (trade for parts)
It has sleeved pushrod holes....it would appear whoever did the porting must have gone through the push rod holes....they are now sleeved. Looks very professional.....however, surely this would really disturb the laminar airflow of the inlet track.
Anyone have experience with such a modification??

[iain1967s]

I got one exactly the same. Ported 1805 sleeved on the inlet for #3.

I had to drill it out to enlarge the ID of the sleeve slightly, because a standard pushrod end wouldn’t fit through.

[r.tec]

Happened to myself while opening the channel.
- bored the pushrod hole out
- made a tube on my lathe with a bit of oversize
- pressed the tube in
- bored the tube to make way for the pushrod

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Are you sure the flow is laminar anyway at this spot?

[360gts]

Whoever did this head knew what they were doing....very well machined etc.
Tubes were pressed in and nicely flared on top.
Still wondering what this does to the airflow in the inlet port!

[swifty]

This was common on longman heads . Had a few over the years that were sleeved push rod heads . ... ken

[360gts]

This was common on longman heads . Had a few over the years that were sleeved push rod heads . ... ken

Hi Ken, interesting!
I have two large valve Longman heads here that have larger ports than this head and they are not sleeved.

[swifty]

From what I remember dermott they were full race longman GT15 and GT17 heads . ... ken

[360gts]

From what I remember dermott they were full race longman GT15 and GT17 heads . ... ken

That what I have right here Ken...beautiful heads...inclined valves and offset rockers.

[imack]

My longman gt15 has sleeved pushrod tubes as does my MED clubman head with offset valves. The thick walled tubes aren't visible like the on top photo, they're ground into to increase port width and become almost invisible in the finished port.

[360gts]

My longman gt15 has sleeved pushrod tubes as does my MED clubman head with offset valves. The thick walled tubes aren't visible like the on top photo, they're ground into to increase port width and become almost invisible in the finished port.

Well I'll be a monkey's uncle!!!!
After reading this last post...went and checked my Longman GT17 heads....they ARE sleeved....the sleeves are completely invisible inside the ports.
All these years I have had these heads sitting on here the shelf and I never noticed the sleeves.....learned something ...AGAIN!