Tricks from old cup cars?

[Justin14100]

anyone know a few tricks from old cup cars, heard they used larger crank (charger) pulleys cause charger pulleys were rule spec'd.
any other bits and kit they used to bend the rules?

[Yoof]

Rumours vary from the mundane to the slightly crazy.

Larger crank pullies
Camshafts (custom) stamped with OEM marks
Decked block with water pump housing re-ground (height between water pump pulley bolt and block face is measured IIRC)
Aquamist systems in washer bottles!?!

I've not heard such, but I'd be surprised if no-one had switchable maps...

[PeteG40]

according to email exchanges I had with nigel manners who raced there were a lot of mods, but the other competitors used to complain if they thought anything was amiss

he said

'Yes to smaller pullies, but they all got caught ( even my good friend John Holloway) since the scrutineers had a special gauge that quickly measured it. I knew that since I worked at the company...so I did not do that...and no water injection, the parts to do that would have been far too obvious to get passed all of us and scrutineers looking under each others bonnets etc . The drivers were worse than the scrutineers for finding parts and things to query....! Suspicious on the front runners since they were far too quick in a straight line, G60 inside G40, exhaust improvements...fuels,
..may be more in any write ups...
Nigel'

not sure what g60 inside g40 means though!

[Puncharado]

not sure what g60 inside g40 means though!

Sounds like G60 scrolls inside G40 casings, is that even possible? Maybe some clever machining to make them a bit wider, like those G45 chargers.

[Justin14100]

Decked block with water pump housing re-ground (height between water pump pulley bolt and block face is measured IIRC)

is that an advantage? what is that? haha.

60 scroll in a 40 will not happen, unless you want a 20mm gap between the casings. interesting though - bet some of the more rule bent ones where maaad to drive!

[Puncharado]

Decked block is when the block is skimmed and increases compression, re-machining of the water pump housing is so the block height appears unchanged to pass scrutineering.

And perhaps the charger casings can be machined to be a few mm deeper, and then a G60 scroll machined down to match. So you effectively end up with a 43mm width or whatever. That is assuming both chargers have the same profile, I have no idea.

[hardchargin40]

Ive had a modded throttle body off a cup car.  Got it off John Marchant, also bagged a ex cup car gemini phase 1 LSD and g40 gearbox which had a different final drive so closer ratios, 70mph was 3600rpm.  Also grabbed a Sachs clutch off him too.

Not heard about switchable maps, i know that was part of the VW Cup mister-meaners.

I heard about different camshafts being stamped with OEM marks aswell and being revved higher.  Also the larger cranks pulleys.  Towards the end of the series most I heard where running about 125-135bhp.  Peter Studer's car was running 135bhp for sure!



I wouldn't put to much thought into what mods the cup car had engine wise, they had quite tight regulations to stick with staying pretty much stock, there's not alot you can learn in terms of gettign more power out of yours for today.  So unless your wanting to race it in its original form... not that todays race championships for them are heavily regulated anyway, Craig is running about 170bhp.  Boaksey was running 170+ bhp too in the VW cup and TRCSE.

[G40motorsport]

As the G40 Cup was, most mods were hard to get away with, they used to check pulleys, swap ecu's on the grid and check throttle bodies.

Most of the dubious mods came when the cars were run in the Super Coupe Cup to the G40 Cup regs & no longer had a dedicated scruitineer. But most cars had similar mods. I had/tried most of them.

The Aquamist thing was done towards the end of the Super Coupe Cup. Was obvious what had been done as certain cars re appeared with washer bottles in & had Aquamist logo's all over them. Didn't make them win though!