Thanks for the suggestions Dave....I love the way there's always so many ways to solve what is essentially a simple problem....going faster for longer.

The bonnet vents are definitely a no-no....as we're not allowed to change the outward appearance of the car, and an auxiliary rad would give some of the eligibility committee heart burn.

Question...has anyone found a smaller diameter crankshaft pulley that fits with limited disturbance?

A little tester for the forum.....

I've never had cooling issues on my race car, even on over 30deg C days, and that just has a standard 2 core Bellett radiator. And a good quality thermostat is a must as it restricts the flow enough to hold the water in the radiator so it has time too cool. Not using one means the flow is too fast and heat doesn't dissipate
An old trick on our roads cars was to raise the back on the bonnet about half an inch tho. That let's a lot of hot air out. And on another race car I saw similar holes cut into the inner guards between the shock towers and the firewall which seemed to work too.

Another trick, if u havent done it, is to make a plate that directs air from the 3 cutouts in the lower stone tray to the radiator so it uses that air as well because if u look at a normal Bellett, that area just lets air into the engine bay and not thru the radiator. That higher pressure air can then stop the hot air from exiting under the car, as hot air always rises.....

All good ideas. Different engine too, Brett..........

Good stuff Brett......great minds and all that....have a look at what we did the other day!

The pulley on the SOHC is a different one to a standard G150/G160/G161 engine. A one piece machined part.
The pulley on a G161Z/G200Z is two piece. A drive boss with the pulley bolted to it. As some of these engines
are used in different drive modes Air conditioning, power steering, pollution pumps etc. there are pulleys bolted onto the face of the main pulley. And are smaller in diameter. You may be able to use this type of drive just by measuring and machining the boss (if you have to) to suit the crankshaft. The front cover seal is the same for all the engines I have mentioned including yours. The next step is a suitable pulley off of any brand of vehicle. You will have to allow for the timing marks on the back.
Another way , and hopefully you have a spare, machine the original pulley off and find a suitable pulley to bolt onto it. In effect making your own boss.
Some Isuzu diesel engines utilize the two piece. Might be a machinists nightmare as the seals and design are different.
How are we making out over here "Teach".

Dave.

I'm guessing your water pump is in good condition without any corrosion? I haven't seen an overheating problem other than head gasket trouble that wasn't fixed by a new radiator core.
If your block is clean which it obviously would be, then I don't know.
I know that theory of the thermostat keeping the flow correct, but my experience of running without one is it just runs cold. I always run one.
Are you able to have a test thrash before your next meet?
Good luck with it.
Matt.

I' m sure you went to your tuner guy to get the engine in top working conditions, but a possibility could be an ignition which is set a bit too late or mixture which is too lean. I wonder, how much bigger is a chevy luv radiator compared to a bellett?
Gr Dick

You're right Dave, the pulley bit all seems a bit of a frigmerole.......basically we want to slow the water pump down, in order to reduce cavitation.
For this part of the car's development though, we shall do it one stage at a time, in order to learn how effective each mod has been........
........so we'll start with the cheap and easy mod of improving the old 'cold air in, hot out' effectiveness.
Great to hear from you Dick.....and as you might imagine we're happy with our mix and timing.....the change really is us sorting the short diff and GT box, this is allowing longer sustained periods of peak revs.
And incidentally we're running my trick ally rad that you can see at the bottom of page 34.
Oh, and this was spotted on YouTube...this is the first couple of laps of the field rounding Druids.

https://youtu.be/I9XfrBjpLco

Here in development corner our work is now done (until after the next race).
Having tried to manage the airflow better with work previously mentioned, we reckoned it was time to stiffen the front up a little.
I couldn't remember the rate of the original springs we put into the car, it was after all only an educated guess anyway, so we had them tested and it turns out they were 475lbs.
We've gone to 575lbs, and reduced their length by an inch to better level out the ride height front to back......we've also fiddled with the camber and shocks.
To say that I'm looking forward to seeing how this has all changed the car's characteristics would be an understatement.
This little car is, once again, really floating my boat.

I found some Brands Hatch Video / footage on youtube, by a highly prepped Austin A40, who is chasing Mark in Rolie.
Think that Austin must have cost a fortune ...
Have a look at it yourself:

https://youtu.be/zhYeKNvhn9U

Gr Dick

What a great bit of footage!!
Good finding Dick

Yeah, good find Dick...cheers. You're right that A40 is a high tech piece of kit, and I can't remember why he ended up qualifying behind me.

Anyway we're back to Castle Combe this weekend, and at last we've got the final instructions, so here's the entry for our race.

A good old mix, I think you'll agree.
You might remember we had a good race here this time last year, and it looks like the conditions will be similar........so with our new lowered and stiffened front, and hopefully better cooling, the comparison of times will tell us a lot.
A pleasing development is my old mate 'Techno Chris'....have a look at this viewtopic.php?f=14&t=2158 ....has finally got a replacement engine (from Aus, of course) and is taking the old Cresta out for a run......I look forward to waving him through on about lap eight!

Back to earth with a bang...........six laps into qualifying, the dreaded death rattle. The car was absolutely flying, I was less than a second from last year's race pace, and I was still scrubbing in a new set of boots.
We reckon our stiffer front end has given us that little extra cornering speed, and surge has starved the bottom end. I'm told on good authority that if this happens, it's usually number 3 that goes....and guess what?

It's number 3.

In a warped 'racers' way, finding this has pleased me, as I was terrified of not knowing the cause of this end failure......at least we know what we have to do to prevent this from happening again.
So the planned winter engine build has just started a little earlier.

Never a good thing when it happens but as you say it's a good thing knowing the cause and even better knowing how to prevent it happening again in the future.
At least you have more time up your sleeve for the rebuild

True enough Sticky....and we need it even more, as it turns out all the clattering has shaken a clevis pin loose....

....and now we have to re-bore as well......so it's a full on rebuild now.
A year or two back I found some NOS flat top 1.5mm over pistons...these will put us up to the best part of 1900cc....we have time to properly balance every thing, and put the flywheel on a further diet....so hopefully this cloud has a silver lining, and by silver lining I mean a second or so!

Whilst the block is at the machine shop, we've created our new 'deep' sump in order to counter the surge.

This has been an interesting exercise, also involving extending the pick up and accompanying shroud.

And finally giving the end product a coat of 'speed' paint.

Don't you just love the development process?

I love speed paint....... I gotta get me some of that for Donkey

Hi Pom.
Have you gestimated how much extra oil is needed. It looks like half a gallon.
Better more than not enough.
That gudgeon pin clip must have made a racket. I had a circlip on a rear axle short shaft let go once.
The noise it made would not have been the same as what your engine had produced.
You may have mentioned it before, but I'm going to ask. Did you get hold of another engine after the debacle with freight out of the USA. .

Dave.

Dave, there's another 1.5 litres, so just over a third of a gallon......and the sound of me swearing drowned out the circlip noise!

The trouble I had with E Bay and the dreaded Global Shipping Program was with an engine for another, non Belletty, project....I never saw that engine incidentally.
But I did successfully import two LUV 1800 engines from separate sources in the States. Finding them is relatively easy....it's persuading the seller to pack and send them that's more tricky.....some of them won't even send anything to neighbouring states, let alone across the Atlantic.
Mark