Golf & Ibiza kitcar engines compared

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Golf 3 kitcar vs Seat Ibiza - they sounded very different (albeit with different induction systems on them, the Golf with 8 injectors in the inlet, the Ibiza with 4 in the inlet and 4 in the bellmouths). For my money, the Ibiza was revvier.

The Golf was ABF tall block, but the Ibiza is 99% 1.8 ADL bored out to 2.0, short block (akin to KR) since it was homologated before the Ibiza was ever productionised with an ABF.

Couple of vids:

[YOUTUBE]4OtaRhk_rX8[/YOUTUBE]

[YOUTUBE]uSFU3_v2pvM[/YOUTUBE]

 

FWIW, I have max revs listed for a Oct 1998 Golf kitcar motor as 8,000rpm. I'll check other info I have to see if consistent.

The last Ibizas went to 8,900rpm, but that's not necessarily like for like, as that's a year down the development road, 1999 spec (Golfs were Mk4, 20v by then).

There are 2 subjects here (edit and in the old thread - long rod vs short rod motors): ultimate spec and road spec, but the translation back from ultimate to road should surely bring the reciprocating trends with it?

 

Given that these short rod and long rod 16V kit car motors are pretty much ultimate spec engines (audi touring car aside), what were their relative power/torque outputs?

 

For the Golf kitcar, 245NM (Oct 1998)

No works-declared Ibiza torque outputs to hand.

 

power?

 

Golfs in the 260-280 range from 1996 - 1998.

Ibizas started out at 250/255bhp (1995), incremented up to 265 before they showed an early engine builder door after shearing off too many modified oil pump drives. It then climbed up to 285bhp max declared (1999).

As said, the behaviour of those Ibiza engines appeared to be much revvier, and I doubt it was gear ratios. How does this translate to appearance on a power graph I wonder.

 

so basically the same power, long or short rod, and certainly not a "massive" difference

Ibiza and Golf had different homologated main gear ratios - ibiza's much closer together - likely to give the increased 'revvyness' observed

Golf:
33 11 3.000
32 14 2.286
30 17 1.765
28 19 1.474
26 21 1.238
24 23 1.043

Ibiza:
11 35 3.182
15 35 2.333
18 33 1.833
20 31 1.55
22 30 1.364
25 31 1.24

 

245Nm = 185lbft. Would like to see the WOT curves for that. This level of torque is approaching OE turbo level of torque for mere mortals with average engines.
Ibiza in that clip appeared to be buzzing much higher than the Golf clip.

 

You've been blindly copying homologation data off the SQS site. Those aren't Hewland ratios - they're from Group A standard plenum cars on a 02A/J cable change box, circa 220bhp. Nothing to do with the Ibiza kit car at all.

 

Correct these ratios are from the SQS site. So what Hewland ratios were used then?

It seems that the Kit car engines were quite a bit different than stock long rod / short rod engines anyhow - ibiza 'short rod' ADL-base engine using 84mm bore and 89.5mm stroke compared with the standard 1800 81 x 86.4, or more normal 2L variant of 82.5 x 92.8.

I wouldn't mind betting the long-rod ABF-based Golfs were using the same 84 x 89.5.

It looks like the power outputs were pretty much the same short rod / long rod.

As for torque, Chris said 245Nm for the Golf - 185 ftlb in real money.

I have found 2 separate refs for torque output for the Ibiza - 220Nm @ 6500, and 22mKg @ 7000. 220Nm=162ftlb and 22mKg=160ftlb. Less than the long-rod golf.

Interesting - maybe the long rod engine is better after all......(the point of this discussion).....but this does not tally with info I have from a very good builder of VW engines who could build these engines in long or short rod configurations for particular applications, chooses to mainly do the latter, but tells me that there is very little in it.

Incidently, it looks like different engines were used by Seat / VW for different rally events with different cams and mapping to give different power characteristics, so it is very hard to really find out what these engines were really doing.

 

I hate to think how much they spent on these cars... special engines for events... yikes!

 

just been thinking some more about this - why would seat go to the bother of homologating a different set of ratios to those being used in the golf?......closer ratios........suggests a deficit in torque to me.......

 

Wouldn't they have more than one set of gear ratios homologated, and swap the 'box for different events? I'd have thought you'd want closer ratios for gravel and twisty mountain roads, and a bit longer legged for more open, faster events.

I'm not sure what the regs would have permitted, but you'd think that on some events there would be good justification for a gearbox swap mid-event at a service halt, as the character of the stages changed.

Anyway, interesting though the discussion is, I think we're getting a bit off topic - from base engines for an ITB install, to kit car gear ratios. I think that's out of scope for most people's knowledge budgets on here. Thread split?

 

Dear me, rally manufacturers always have had different spec engines, gravel (more torque) and tarmac (more power). This is nothing new at all, they're always doing it.

They always homologate heaps of ratios and final drives, add homologation extensions (VO-designated docs). As Mike says, different events, Australia + NZ are very fast.

Eg 1 a change in wheel size necessitates altered ratios - see Ibiza kit car Evo 1 & 2. The box itself never changed.

Eg 2 the Mk2 FWD Golf was latterly homologated in Group A with a cable change box, even though it never had one.

Have a rake through the docs on VWM.info for an idea.

Rose had 2 engines for his Mk1 Slick 50 car back in the day when he was winning it, one short stroke and the other long.

Agree the thread has definitely gone a bit OT !

 

Going back to rod lenght ratio
The kit car engine have 150 mm rods
Don't they?

 

Golf or Seat kitcar?

I stumbled over a mention of the Audi BTCC running 152/153 rods here when compiling 4cyl engine data.

 

Golf 3 had 160mm rods, Seat had 149mm

 

This probably wants splitting as suggested earlier, but I'll put this here for now:

Golf kitcar crankshaft min weight: 12.15kg
Seat Ibiza kitcar crankshaft min weight: 10.63kg

Both are 90mm.

Also the Ibiza saves another half kilo on the flywheel.

Contributes to why the Ibiza is as revvy as it is?

 

Are they running the same bloc?
11mm that s almost the difference bloc height between
The short (bubble) and tall bloc
With 2 kgs difference on rotating parts for sure they will sound different

Romain

 

No, the Ibiza is an ADL block, 16mm shorter than the Golf on an ABF block - mentioned here