Iv'e got these 2 engines (to be delivered this weekend) and am noticing subtle differences between them from the pics. In the second pic, there are what looks like cut off hoses just below the spark plugs - but in the second pic, they aren't there. Can anyone shed some light on the differences in engines or school me Or tell me what engines I have here. Cheers

Assuming the engine heads and Carbies etc havnt been changed they are both 998cc rod change engines.

Both engine number prefixes should begin with 99. This number pad can be found on the block just below spark plug 1.

If the prefix is 10 then it's an 1100cc.



Sent from my SM-N960F using Tapatalk

_________________

Cheers for the info - do you have an idea about the parts that look "cutoff" just below the spark plug there?

Air injection into exhaust ports.
Used in late 998 engines which had an air pump.
Part of the emission control system.

_________________
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.

As the doc said.
They were metal tubes that pumped air into the cylinder via a small compressor that bolted above the alternator on a bracket that came off the thermostat housing.

Pretty much a non existent setup now days.

Sent from my SM-N960F using Tapatalk

_________________

The air was pumped into the exhaust ports, downstream of the valves. Not into the cylinders.

_________________
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.

Yes sorry doc, should have worded/explained it better.
Thanks

Sent from my SM-N960F using Tapatalk

_________________

Thank you very much - great info! So in saying that, with this engine, do I need to source a compressor to make it function or can the tubes be welded (forgive my inexperience) closed.

No, you don't need to find a compressor. The tubes have been cut off and probably soldered over, they'll be sealed well enough for what they do. You could take those cut-off pieces out and replace them with grub screws to make it tidier

_________________
did I tell you that I won a trophy?

Great! Thank you I'll do exactly that with the grub screws.
Cheers

For reference this is what the Exhaust Port Air Injection looks like

The grubscrew size is 7/16 UNF.
Or if you're a cheapskate like me, use old seatbelt bolts and grind em flush.

_________________
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.

LOL Thank you so much! I was sitting here thinking, how the heck am I going to find the size I need.. Legend

The emission equipment was part of Australian Design Rule 27A and is no longer required, ADR27A has been repealed and no longer exists. (despite what a couple of self appointed trolls say)

You can't buy leaded petrol any more to make it work properly anyhow.

Further reading...

https://www.rms.nsw.gov.au/about/enviro ... dards.html

https://www.infrastructure.gov.au/vehicles/environment/

_________________
"Show me the Mini!"