This is an EPIC thread at nearly a thousand pages!

Been running Go engines for years - had mainly gold head 7 ports, couple of .25 race engines in truggy, race .28, .21 3 port R which has only recently expired and an MG66 which has also recently passed away through lots of use!

Go engines are more or less forgotten in the UK - most people favouring Alpha for cheap engines and various rebranded OS options like the Bullitt, plus the usual favourites from Novarossi and RB etc.

I lucked into one of a couple of Go GXII-5RHO engines and a matched hard coated pipe being sold off cheap

Clearly a very different engine to look at compared to the earlier engines I've been used to - crankcase looks a bit OS/GRP/Technopower. Still has the 2 needle carb, which having read on here means it's not the latest version.

Reason for posting is regarding running in - I've tried searching but just using a common term like 'break' pulls 20 pages of results lol

I've done a tank on the box after pre-heating with full throttle/very rich HSN and wheels barely turning, then pretty much followed the Massive Mods approach to breaking in in terms of temps to pre-heat to and what to aim for heat-wise while breaking in. Did a second tank on the box at 1/4 throttle etc and then started to drive around.

I've now done quite a few tanks - probably a third of a US gallon of Byron 25% so about 6-8 tanks if not more. At the moment the engine has been heat cycled every couple of tanks with foil wrapped around the head to keep the heat in. It's getting up around 250F running like that - HSN is still flush.

Pulled the plug to afterrun oil it this evening and it will still happily stick at tdc with just finger pressure on the flywheel.

I checked the bottom end adjustment and it's about 1 3/4 turns in from flush and idle is pretty stable.

Question is at what point is the bottom end setting heading towards too lean when running like this? I haven't run in a new Go engine for years - last two race engines were OS VZ-Bs - so a bit out of practice.

I don't have track access to run lots of tanks so have to go for car parks etc - I'm racing on astroturf on Sunday with this engine so what advice would the experts give in terms of getting it ready for that?

I should be able to get some more time this week to run some more fuel through - otherwise I'll be very busy Saturday wrenching on the car to get an astro setup and running in the engine some more!

I wish I had a spare engine I could run instead, but the only other option I have is my 'old' MG66 with a GXII-5R piston and liner which hasn't seen a drop of fuel either since being rebuilt!

Regards

Adrian