Windage tray in X1/9 aluminium sump or not?

[MichaelNooij]

Dear Guy and forum members

I own/race a Group 2 Fiat 128 3P for competition.

I have following question: in your book you write about the X1/9 sump but not about using a windage tray for this sump. Under you see a picture of the PBS windage tray, which I can re-fabricate.

3eezor-1911a739d15ce29c3db621fbafddd1f7.jpg (594.13 KiB) Viewed 1860 times

What is your experience by using this sump in racing application, meaning hard cornering and braking?

I have now built in this sump without any modification, and have not been on the circuit yet with this sump.
I know 2 Germans using the same sump in their race 128 Coupe but it is not clear if they have modified it.

The tray in the picture needs double sump gasket and assembly/disassembly of the sump when installed in the car is not an easy job then.

Thank you,

Best regards,
Michael Nooij from The Netherlands

[Abarthnorway - Remi L]

Hi!


I once used a similar type baffle in a race 128, and we had no oil problems during race conditions.

If it is "good" or not I dont know, but I suppose we would had run into problems if we hadn`t used one, considering the shape of the original sump. Never seen the alu x1/9 though.


Best regards

Remi Lovhoiden

[Guy Croft]

I will answer this as succintly as I can. The problems with wet sump are:

1. Oil gets whipped up by crank and aerated
2. Oil gets aerated sloshing around
3. G force under acceleration, braking and cornering throws the oil all over the place (away from the pickup)

Moreover as with any oil system if the oil in the sump is allowed to get too hot (over 85 deg C in my view) then the oil pressure will naturally drop because of the higher rate of bleed from the bearings.

A windage tray placed between crankcase and sump will help with (1) above, but - if located quite high above the oil level as yours shown will aid to a much lesser extent with (3). Baffling around the pickup is always a good idea and nothing works as well as trapdoors, here is a VW sump from the USA which is a pretty example of a good baffled sump with twin trapdoors. Though I would point out that, having made hundreds of sumps, you have to be in fairly serious production of one design to achieve this standard - and - make a profit too.. To be effective, trapdoors have to have a decent volume of oil behind them since their function is to retain that and only open and release that oil over the pickup in high G situations.

The X19 has a small advantage in that it has quite a deep 'well' which always helps to contain the oil near the pickup and it has a mildly effective top baffle - I have known folk do circuit race with it 'as is' without oil starvation problems. Baffling might perhaps consist of removing the top baffle and rebuilding with aluminium bulkheads & trapdoors etc.

An oil accumulator is also a very worthwhile investment, Moroso shown below. This stores oil under air pressure and automatically discharges when the oil pressure drops.

In short - anything you can do to improve a wet-sump layout is a good thing and there is no such thing as a 'perfect' setup.

Hope this helps some,

G

[MichaelNooij]

Thanks from prompt answers,

I had already the doubt that the windage tray is to close to the crankshaft. for that I will not use it.
The oil pump is filling the big hole in the top baffle. So the oil will not easy go away from the pump pickup. I will try it as it is.

The oil accumulator seems to me a good investment.

Btw, I have read about the Uno turbo pump in the forum. This one I have tried also in the past. It is a high pressure pump that is why it has 2 teeth more than the standard unit. It gave me a steady 7 bar oil pressure with the extra effect that the drive gears for pump and distributor wears to very sharp teeth. With extra problem no steady ignition anymore because of extra backlash of the gears.

The Fiat 128 pump with 8 teeth gives more volume and for more pressure I have put a 2 mm thick ring under the spring. Result is 3 bar at 1000 RPM and 5 bar from 3000 RPM. That works for my engine ok.

For oiling the drive gears of the pump and distributor I drilled oil holes in the shaft and between the gear teeth with cobalt drill.

I hope that this is interesting information for anybody.

Best regards,

Michael

[TomLouwrier]

hi Michael,

Good to hear you found out that you can have 'too much of a good thing': the very high pressure from the Uno Turbo oil pump and the rapid wear on the drive. That may be a surprise to quite a few people.
I like the added lubrication for the gears. If that hole is not too large (causing pressure drop elsewhere) it will keep those gears well oiled.

regards
Tom

[Guy Croft]

Some very interesting points there Michael, thanks. Especially this:

With extra problem no steady ignition anymore because of extra backlash of the gears.

Never given any thought to that before. Has anyone else?

G

[TomLouwrier]

It's a pretty common effect in older OHV engine designs where the distributor is driven off the cam shaft (which is in the block) and the cam shaft is driven by chain from the crank.
You would not see much of it in a TC with a correctly tensioned cam belt.

regards
Tom

[Haymanracing]

I run one of those PBS windage tray's in my sump - i run an X19 1500 with a standard 128 tin sump. It does say on the instructions to run the oil level 1 quart above standard. I also however run a thermostat controlled oil cooler, and i've had no oil related problems with my engine with this setup, and thats throwing the car hard enough into corners to be on two wheels. I will however be investigating similar to Guys pictures of the Moroso sump on my DOHC engine, using gates around the oil pickup.

[IVOR BORLAND]

Hi,

I also have a tarmac 128 3p rally car that uses the same windage tray with the X1-9 ( modified ) alu sump. Why a modified sump you may ask. The reason why is that the engine in the X1-9 lies at a different angle to the 128 so the sump base angle is different which may mean that the pick up angle will not line up with the sump base and NOT pick up oil.You can use the X1-9 pick up as well but as the engine is tilted at a different angle the oil in the sump will lie at a angle to the pick up and under hard driving you may drop oil press.

My sump was cut and welded to match the std 128 sump (angle,vol and size).The std 128 pick up and pipe should be ok as long as the X1-9 sump is cut and welded as the std 128 sump.The pick up should be close enough but not too close to the base off the sump. Keep std size and it will be ok. If you cut and weld the sump you need to match the sumps so that they are identical in angle and size.

The advantages off using the X1-9 sump is that it has ribs under the sump which aids cooling, may be stronger as it is thicker but I do not know for sure, you regain ground clearance under the car. Sorry for ranting on but I wanted you inform you what is reqd to use it correctly. It may sound like a lot off work but you seam to have all the parts, all you need to do is LOOK and COMPARE the differance youreself, you will see what I mean. I have not had any problems since the mod was done but the oil accumulator is a good insurance as a new engine would cost a lot more.

Hope this helps,Ivor.

PS Can you get in touch with me as I know off no one else running a 3p and info and parts are hard to get. THANKS.

[Haymanracing]

Oh i forgot to add my X19 engine runs the 128 oil pickup along with the sump (not a big deal to change) in a 128 sedan.
I've had no probs with this setup, but agree with Ivor. The only problem i faced was ground clearance as the X19 sump is alot deeper than the 128 one, and hangs alot closer to the tarmac.

[WhizzMan]

Did you have that sump zinc plated after you modified it Guy? It looks very nicely done.

[MichaelNooij]

Hi all,

I use the X1/9 pump also in the sump. Before I had the Alu sump of the X1/9 I used this pump in a lowered standard sump without trouble, only the pump inlet was to close to the bottom to my opinion and I good catch a series of these alu sump and installed it.

I know 2 other 128 race cars in Germany use the same lower X 1/9 sump but I have no information if they modified it.

For tarmac racing it is not that big problem that the sump is to low, only the curbstones can be hard. The Moroso accumulator will help in case of a problem. I must definitely install it.

In the picture you see the old steel sump under the car.

And for Ivor: if you need any information or parts please ask. I have plenty information, I cannot sell all my spares but I have enough sources or samples for re-manufacturing.

I will plan a new thread about the car but takes a little time.

Best regards,

Michael

[Haymanracing]

My car sits lower than that on the track (it is a sedan also) - so its a risk i didn't want to take, but yes i do suspect the aluminum X19 sump offers more cooing - probably why they made it alloy in the first place being rear mounted instead of front.