Golf & Ibiza kitcar engines compared

Oooops sorry
That s not much rod lenght increase for the golf
But that's a big jump for the seat

Romain

 

I remember spectating on all of the mainland BRC rounds during the F2 era. The Golfs and Ibizas sounded so different. The Ibiza's, especially the Evo2 were higher revving motors for sure. I remember Gwyndaf having to drop cogs here and there after dropping off cam. The Golfs were more gutsy, regularly a gear higher coming out of corners using the torque. The Ibizas had a closer stack of ratios i'm sure. Great times.

 

I've split these side discussion posts out from Which is the best engine to go with ITB?, now that the other one's continuing down the road engine route.

More data on post 2 of this thread, for those who may have missed it.

 

The Golf Kit Car have an ABF block, but with a shortened height !

 

Why would they shorten the bloc?
And how much shorter ?

 

Hmmm, time for a table:

	Stroke	Rod length	Stroke x 0.5 + rod	OE block height	Distance from wrist pin centre to OE deck
Golf kitcar	90mm	160mm	205mm	236mm (ABF)	31mm
Ibiza kitcar	90mm	149mm	194mm	220mm (ADL)	26mm
Audi BTCC/STW	88.1mm	152/3mm	196.55mm	220mm (6A/ACE)	23.45mm

The Golf has the largest relative distance from wrist pin to OE deck (irrespective of actual deck used on Ibiza/Audi), so with the 160mm rod configuration, it looks like they stopped increasing rod length and decked the block instead.

Reason: inherent durability issues with going too long on the rods?

 

Maybe, because of the shorter stroke -2,8 mm and they have reduced the height of the piston for saving weight (like Audi DTM)

 

So in answer to Romain, I reckon very estimationally, 5mm off the block to get level with the Ibiza's apparent spec. Would that go into the water jackets?

/nips off to check Brian.G's cutaway

The Audi ran higher compression and so should probably be ignored for that reason.

 

Looks doable enough to me - 6A block, but the top edge construction should be no different on an ABF. Just a question of any issues with oilways and water ways:

 

Looking at these blocks, it looks like some metal has gone astray:

Standard ABF block, infinity's, previously used on the BTCC thread:



The thinnest bit of horisontal ridge (left-most arrow above) isn't visible here:



And the vertical section marked does look shorter

 

I guess they managed to compensate the deck difference
For the timing belt with vernier pulley to get the timing right
They could skimmed even more the bloc
to get the piston pin height as small as possible
To gain even more weight on the piston

 

Piston pin is 18 mm on KC, instead of 21 mm as standard so maybe they can push upper the axle even more !

You can see that KC is skimmed because :

Shorter timing belt : From Polo 16V !
Shorter screw for cylinderhead : From 5 cylinder 20V audi !

 

Will have a search on Ibiza KC cambelts

 

Now that this data is up, interesting to see how apparently innaccurate this Eurospec page is:

http://www.eurospecsport.com/products/engines/2p0-kit-car.htm

You'd think that the page/company was about VWs, no mention of Seats, yet it's obvious that 'FIA approved' kit is for a 220mm block