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Wet or Dry sump??
1 litre screamer - 9/7/06 at 07:43 PM

I've got a kawasaki ZX12r engine to fit in my lupo, i know its not a hmm, 7 based project! but its going to be done by my own hands and built not bought. Now i have conflicting reports on the sump issues. Some people say that as i'm keeping the engine in the same orientation as it was designed it shouldn't need anything more than a good baffle plate fitting, yet other people are telling me that its in need of a dry sump otherwise its going to have oil feed problems. Help! which is it??
Another quick question, has anyone fitted a single rear brake on the diff rather than staying with the standard approach of a caliper on each rear wheel? I'm thinking along the lines of the engine producing the extra braking and a single disc just to balance the braking. this would also save on weight.I will quickly add, I'm having huge discs and calipers up front.

ChrisGamlin - 9/7/06 at 08:08 PM

I think its fair to say that the jury is still out on the ZX12 for heavy track work without dry sump, there have been a few go pop in race cars with wet sump, but some trackdayers have them fitted with only a baffle and they are fine.

Having said that you're not going to be generating as much cornering force in your Lupo as in a Locaterfield so I suspect you'll be fine with a wet sump.

As to the braking concept, I cant see how it would work unless you had a locked diff, otherwise you'd not be able to ensure each wheel had equal brake distribution. Also I suspect it would fail an MOT like that, as they test each wheel individually on their rollers.

Chris

Mike S - 9/7/06 at 08:14 PM

From what I have seen on here the ZX12R seems to be pretty bullet proof.

I would think that a baffle plate would be a worthwhile investment though given that they only cost about £30.

Are you planning on using the car on the road? if so you may have issues with a single brake on the diff. even if it is limited slip. Of course I stand to be corrected.

I would have thought that the Lupo whilst a small car, would still be a bit on the heavy side for bike power?

Mike

1 litre screamer - 9/7/06 at 08:38 PM

I forgot all about the MOT and braking! thanks for reminding me on that,
The car will be mainly for road use but will find itself on trackdays. It corners very well as its sat on almost solid coilovers and 150mm lower than standard, the antil roll bars are extremely stiff so its possible to create a fair amount of force. As for weight, it is completely stripped of anything that doesnt do a real job. I weighed it on our corner weight scales a few weeks back and saw 502kg. The lupo engine is tiny so doesnt weigh much, or produce much power! my aim is to get as close to 400kg as possible. I have already cut out all of the 2nd skins on panels and carbon doors,bonnet,boot and plastic windows are soon to be fitted.
Thanks for the help guys.

ChrisGamlin - 9/7/06 at 08:38 PM

quote:
Originally posted by Mike S
I would have thought that the Lupo whilst a small car, would still be a bit on the heavy side for bike power?
Mike


I have to agree, you'll need to get it down to the 550-600kg (absolute max) mark to make it worthwhile, seems a lot to me from a car that weighs best part of a ton with its original engine installed.

Naccers - 10/7/06 at 01:27 AM

Aye, my fessy weighs about 800ish but has got a roll cage. Is the lupo a big plastic car thou ie wings etc??

Hellfire - 10/7/06 at 07:25 AM

We have a ZX12R engine in our Indy and have been VERY careful with our engine and basically done lots to stop our engine popping. We have currently installed chopped and modified sump, extensively baffled, modified PRV. We haven't dry sumped as we have heard of many problems with leakages and other related problems. We also negated to install any secondary oil pressure systems after lengthy discussions between ourselves.
We have installed a SPA racing oil pressure gauge which is very accurate... and on tickover we typically saw 5psi (which is normal) rising to 70psi 'ish at maximum rev's. Only on very difficult corners which were severely undulating/fast corners did we see a slight drop... personally our doubts have been unfounded as our engine performed miraculously under very hard trackday conditions.

Just do it - the Polo won't be generating any near the same levels of force as most cars on a track due to it's comparative high COG and narrow track/wheelbase.

Hope this helps satisfy your query.

Steve

ChrisGamlin - 10/7/06 at 06:16 PM

quote:
Originally posted by 1 litre screamer
I weighed it on our corner weight scales a few weeks back and saw 502kg. The lupo engine is tiny so doesnt weigh much, or produce much power!


Is that 502kg figure with or without the current Lupo engine?

1 litre screamer - 10/7/06 at 07:31 PM

the weight is with the standard lupo engine, the car is basically made of the thinnest material VW could produce. If i try i could press a dent in every panel with one finger!! The car started life at 84kg, since then the whole interior, including the dash has been removed. All thats left it a seat, steering wheel and little dial panel. cage too but thats all gettting moddified later on to accomodate the new rear spaceframe.

DIY Si - 10/7/06 at 07:34 PM

Will it end up stiff enough to actually drive about in?

1 litre screamer - 10/7/06 at 08:05 PM

with all of the cross bracing and webing that its going to be having it will be very stiff. It already lifts the rear wheels when cornering.even in carparks at walking pace!