Split: how they got > 200bhp + on a single plenum 16v

Overdue split from the nonsense ABF power Ibizas thread: http://www.clubgti.com/forum/showthread.php?t=188950


In 1995/6, Volkswagen Motorsport / SBG Sport were getting ~ 220 bhp out of their rally motors. ABFs, on plenum injection.

These were short-life engines, built at high expense by Lehmann, tuned to the max to last a rally or two.

 

Chris,

Interesting comparison between that and Ess_Three`s (197bhp ABF) - RR dependant as always

 

But 200 & 220 are poles apart on a plenum

 

Plenum - you have pictures please?

Too much time on my hands - Easter break (sort of) and no Golfs out here, spent yesterday looking at Ess_Three`s plots vs mine (9A) and wondering what next for me?

 

@ Golfs

No immediate pics, but the diags are in the kitcar manual on the VWM site (the manual is part Gr.A / part kitcar).

 

Indeed they are...and the usual dyno lottery accepted, I just can't get over 200 with the standard inlet manifold on...no matter what work is done to it.

Maybe on a 2.1...
But if you can't get the air in for a 2.0...how is a 2.1 supposed to make better use of it?

Sounds like hogwash to me...not enough work done to get the air in or out...and it's doubtful he's even maxxed out the standard injectors at that spec.
And how much torque? On that spec...unlikely.

 

Ahh...thinking of this..
I was speaking with Bill Solouf (sp ?) at Bildon Motorsport several years ago who had his hands on one of the VW Motorsport ABF inlet manifolds and lower injector housing...
I can't remember the ins and outs, but seem to think the VWM part was 0.5mm larger internally (listed as internally and verified externally with a mic).

Basically, it wasn't worth the cost to me when I could attack the standard inlet/plenumn with a die grinder and see what I could do...so I didn't buy it.
The TB was the same. I remember that...as I seem to recall was the lower section...so it was only the runners over the top that were larger by 0.5mm.

Would that give another 10-20 BHP?
Doubtful I'd say. It's hard to say quite what it would be worth.

 

Interesting this is what they were up to.

In rallying, it'd be worth doing, just to capitalise on the Group A regs and homologations, but for how much ?

And then the components would be near worthless as soon as ITB kitcar regs came into play.

 

ABF with STD inlet manifold and TB
209 Ps @ 6637 rpm
247 Nm @ 5436 rpm

3500 100 PS corrected
4000 121
4500 144
5000 164
5500 193
6000 204
6500 208
7000 202

82.5 x 92.8 mm
Wossner pistons
Ported head , reworked STD valves
276 hydro cams
4-2-1 / 63.5 mm exhaust

 

Higher compression I'd presume aswell to get the power up near that figure.

Still think the 0-60 is about 1 second off for that power and weight, plus I don't remember anyone on the seatcupra.net forums managing to get a mk2 cupra down to 850kg's but I could ofcourse always be wrong.

 

I just did some back calulation on those numbers and I am getting torque values that are more akin to a 2.1 or 2.3.

A fairly modified 2.0 engine achieves near 170lbft and will require higher revs to do so.
This engine runs a fairly std torque profile and rev range and is hitting 181lbft at a factory 5500rpm?
VR6 2.8 torque from a N/A 2litre not at 6500rpm but at 5500rpm?
What dyno was this thing tested on?

 

Think it said somewhere it was a 2.1L rather than 2.0.

 

82.5mm x 92.8mm are the dimensions for 1984cc

 

Don't worry about me, I was just having a 'blonde' moment and not keeping up with what was going on lol.

 

All depends on the dyno lottery...

The figures just don't stack up. Even the strongest 2L valver on plenum will struggle to top 160lbs/ft peak...

 

You could get stock engines to exceed that. But it takes a lot of time and the torque will be based lower in the rev range i.e. from 3600-5500, then it will nose dive. More torque than this and you will need cams+ fettling, compression, more control calibration plus more revs to achieve.

 

HPR pwr/torque plot back calculated from bits of data in post 48.



Must be some sort of STD control system as well 7000rpm limit with a 276?

 

The engine HPR mentions is described as having Wossner pistons in it. They tend to be marketed at around 12: 1 CR. Presumably also got aftermarket ECU and along with those cams, does that seem completely unrealistic?

 

But the torque trace is just as a std ( but optimised) profile just + 30 lbft according to that dyno and its correction. For the cam mentioned and possible piston choice I would expect a torque profile with a peak shifted +500rpm to around 6ishK and slowly ramp down to 7200rpm or so. The huge torque numbers on this plot does NOT make sense for a 2.0 16v, not from what I have seen and tested and driven anyway. But hey you never know...
If that torque trace correlates to any thing I have tested then I would say a peak of 170lbft at 6000rpm with the slow ramp to 150lbft at 7000rpm with a rev limit of 7600 where you may still be making 110lbft.
But I cannot understand what is responsible for the spike to 181lbft at only 5500rpm and why the test stops at 7000rpm where you are still producing 150ish lbft.