Lightweight Mk1 'multi use' competition car. Various pics, testing technology

thanks guys. super sunny day, car going well, was running in class 1B by mistake.
corrected this to 3B after the heats and came second to car 73 by just under 0.1 seconds.
all in all a great day, burnt petrol and rubber, nothing else
there probably was another 0.2 or 0.3 available if I had got it bang on every corner, but I doubt it would go much quicker, as I was using all the revs/gears/brakes/track/kerbs, etc. (tyres took a right pasting)
Jon

 

16V/ABF/KR head on 45's: mk1 is in mid rebuild, last event on grass 18th October. fitting the longer inlet manifold and 45's means the K&N's are just inside the front panel. phew.
Unfortunately, there is no room for a radiator underneath the filters, so I need to find a 14" square one to sit in front of the gearbox.
What do you guys use?
Heard corsa and Honda may fit, but short on time so need to get a specific one ordered.
help appreciated
Jon

 

Found a 'geo metro' one about the right size, in 40mm thick ali.
Going to give it a shot.
65 ebay, so not much to 'invest'
Jon

 

Corsa one maybe ****e, or at least the last time fitted one.

I have a Honda Civic Ally job from e bay should do the trick!

 

thanks, I have gone down the semi custom radiator route. Think I need to post a few pictures to show progress, now its looking a little less 'used'.
The top rad water takeoff is now off the end of the head, as per HPR recommendation. I am presuming the header tank is piped to one of the two side water pump 1" outlets and the other is blanked. That's tomorrows first job.
Jon

 

Custom rad even better!

 

Luminition guts with clockwork advance, in a vw body. Yes, they have been gathering dust for a while. Just need another set for the mk2 now.
Jon

 

That rad looks pretty adequate and a good fit. Are you going to add some sort of plate to keep the air flow into and out of the rad separated from the carbs?

 

Rad isn't ideal, but front end packaging on a mk1 is very tight.
Not sure I have space for much air deflection, but I 100% hear where you are coming from.
I envy the early scirroco's for all that space behind the nose
Jon

 

Ducting around the radiator is critically important, even if it is only a 1 inch stack
Hot exit air isn't really as big a deal as a lot of people make out, of course it isn't ideal but compared to having air hit the radiator and spill around it without actually cool the car will often see a lot of cars with radiators 20% bigger than they need with all the weight and packaging that comes with. Probably one of the most common errors with modified cars, and something you will never see left off a pro built race car


Mk1's are great compared to a lot of moderns!

 

'Race car aerodynamics' great book. If I could only use 20% of its content. Agreed, with Mr Swift. Never had any real cooling probs with the mk1. Put this down to 'full radiator syndrome' (continuous 6mm bleed back to header). If only other makers could follow this.
Still love a mk1, mostly due to its light weight and lift off oversteer.
Jon

 

If it overheats the standard radiator off a 1993 Holden Barina sits nicely under the slam panel. Not sure what the Barina was called in your part of the world but being a GM product (Vauxhall/Holden/Opel) they shouldn't be too hard to track down.



Cheers

Paul

 

Nice mk1.
Aussy weather can be a lot hotter than ours, depending on where you are.
We rarely see 20C+!.
Short inlet manifold and short trumpets/no filters and it looks like you have loads of room.
Mine is out competing (racing on grass) tomorrow, so we'll see what happens
Jon

 

Not sure if the are the GM ones but the Suzuki Swift
The GM (Corsa style) didn't come to Australia untill the the bubble styled one

 

Sport Racer, there's a MK2 radiator (675mm) that's got the supply port that hits the AC on mine here if you need it.

 

Thanks but my MK2 is a write off and doesn't need parts. The MK1 will get it's engine, brakes and dash, it doesn't need anything else. PM me if you need parts for yours.

Cheers and sorry for hijacking this topic.

Paul

 

Swift and Corsa radiator maybe to small for Jon is doing.

 

Thanks Toyo. I'm thinking going to a (relatively) lean mixture may be a contributing factor also.
So hard guestimating jets without RR.
I need a trackday or two with this.
Wishing I had tried some bigger main jets, but its hard to do everything while trying to compete
Jon
Hoping HPR will comment on the end exit head system, as I'm really not convinced....