Matt R that is really impressive. My HS2s will flow pretty close to HS4 flow rates by the time I'm finished with them. I won't reach your figures but that sounds like a very impressive engine. Would love to see the dyno sheet for it.

Matt R have you got that dyno sheet at all?

Looking at the Keith Calver article on the 1098 and how he got 70hp out of the 1098 with only 8.9:1 compression, how realistic would it be since the Cooper S engine with much higher compression and larger capacity makes around the 75hp mark?

There has been a lot of R & D since then. Again, read all the small bore & project 68 articles on
http://russellengineering.com.au/
Everything is there. Dyno sheets and tips on how to go about it.

_________________
1963 Morris 850 Smoke Grey
1963 Morris 850 Shadow Blue
1965 Morris Mini Smooth Van
1966 Morris Mini Van
1969 Morris Mini Deluxe Resto
5/72 Clubman Gt

Scoop I'm waiting for the next instalment of project 68mm from Graham Russell. I would love to have one of the Graham Russell engines but they are a bit out of my price range.

Most of the engine stuff you can get done anywhere: bore, cam bearings, decking etc. If you do a smaller overbore like +60 or +80 you shouldn't need to offset bore the block, which will be easier.

If you want his cam, you can either send one to be ground or you can buy them outright.
http://minikingdomonline.com.au/product ... ight-sale/
You can also get the pistons from him or from minikingdom.
http://minikingdomonline.com.au/product ... l-pistons/

_________________

I've had to purchase a new 295 head as my existing one needed too much work to make it viable. For about half the price I got a very good one with about 40thou shaved off it. Does anyone know who much smaller the combustion chambers would be as a result?

measure them yourself

Get a clear cd or piece of Perspex with a hole in it, fill chamber with light oil (measure what goes in, having a burette or some good syringes will help immensely)

You never know what other chamber work could have been done

_________________
Here am I sitting in my tin can far above the Moon
Planet Earth is blue and there's nothing I can do...



“A turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.” - Jeremy Clarkson

Well, I have a date sorted for completion of my Mini. July 2020 so that i can go on the Rylestone Classic. After reading the webpage it looks like a great event. My question is looking at a small bore block bored out to take 68mm pistons, with the narrow wall between pistons 1 & 2 and 3 & 4, does this cause any problems at all?

A 1275 gasket is used, they seal there OK
A mate and I just did one, the major work was plugging and moving a few water holes to suit the 1275 gasket. Running fine (1108cc using 998 crank and the block decked).

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Thanks Dr. I was a little concerned about the lack of wall thickness between the cylinders.

It is not a recent idea to offset bore them to 68mm, back in the 60s it was a common mod, using 68mm Hillman Imp pistons.
I built three 1220 motors back then including 2 AH Sprites. These are both still running (in Morris Minors).

IMO the biggest concern is the oilway from the pump to the relief valve, which passes very close to #4 bore. If it breaks through, you need to sleeve the oilway there with a thin steel bush and hone the #4 bore, again.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Hi all just about to start my 1098 project so what exactly do we need to do to end up with a 1220cc ? Thanks

Sent from my SM-G935F using Tapatalk

Read this whole thread and go to
http://russellengineering.com.au/project-68mm-part-1/

Read as much of the info on his website as you can and it will start you off in the right direction.

_________________
1963 Morris 850 Smoke Grey
1963 Morris 850 Shadow Blue
1965 Morris Mini Smooth Van
1966 Morris Mini Van
1969 Morris Mini Deluxe Resto
5/72 Clubman Gt

Yar thanks mate i have looked at that im just after it in layman's terms with out all the crap lol

Sent from my SM-G935F using Tapatalk