Beta in Colombia

[Tico]

Hi all, I am so happy to know this exists! I live in Bogota- Colombia where we live at 2.800mts high (unbelivebable), so unfortunadley cars here loose like a 20-25% power due to less atmpopheric pressure and less oxigen. My car is a 2.000 Lancia Beta Zagato (spyeder in Europe). I have converted to twin 40IDF's with an IRESA (spain) manifold specific for that car. Then after, I found that GC existed and bought the book where it says that DCNF are the way for transverse engine (found the book to late as I had expensed like 1.000 USD already!!).
Any way the car runs great and much quicker than before. No problem in hard cornering, braking or accelerating.

I have taken off the air coditing with its radiator, followed the recomended work on the book with the cylinder head and the sump (really important for track days) and installed 40/80 80/40 cams 10mm lift from USA "international auto". It's reving up to 7.000rpm very lively.

The problem I have when racing is high temperature. After 3 or more laps the temp goes nearly to 90-95‚ºC and so does the oil, so I have to back off and let the Alfas GTV and BMW 2002 win !!! .Once I back off the car cools down easily (in half a lap), as the driver temp goes up!. After the first race, I changed the previous thema oil radiator to a sandwich plate from mocal, cleaned every line of the actual water radiator and turned the actual water radiator from one line each 15mm to one line each 10mm (more lines for the same size). This helped in the 2 race but not enough. Water and oil climbes after a few laps. The book says ideal is something like 75‚ºC water, 85‚º Oil, very interesting the case history. But I haven't been able to achive this.

I changed the water pump for a biger from 131 and cut the by pass (following the bible book) but still not enough. When chaning the water pump I saw the block very dirty (this brown stuff). I have tried to clean it up with radiator flusher. For next race I will use "water weter" liquid from USA that says drops temp down (I don't have too much hope, but is before any dramatic changes to the water radiator).
The advance is in 37⼠above 3.500 adn somewhere 10-15⼠idle and is where the car runs fastest.

I use 10w50 elf synthetic, after the oil temp goes up 70‚ºC, the pressure drops. When I used 20w50 the pressure was higher even in hot (why?).

Questions y make myself:
-should I use this oil. A friend says it protects better than 20w50 even if the pressure is lower.
-Could I have an other problem that is rising temp. The advance is there as there is the fastest point (messured with crono).

Thank you if any clues, and rember these magnificent engines are even in countries like main, that sadly you may know for all the negative aspects that eclipse the positive things, like that we race here Lancias!!
P.D I am running to a scaner so that I can send you pictures.

[petert]

I would have said 85‚º on the oil is too cold! Wouldn't you be better running at 95-100‚ºC so any water vapour is eliminated?

[Guy Croft]

Peter, Tico, hi

Here is the actual dyno data that my references in the GC book came from, StIV long oval TC Fiat 2 liter NHRA engine, tested direct back-to-back in summer 1995 at Warrior Automotive, Superflow rig, corrected BHP is shown against preset water and oil temps. I was unable to find out the effect from any book, that is why we did these tests. I should be interested in anyone else's results.

From these results of average water and oil temp deg C plotted against the power I concluded that best settings were:

Water: 70-75 deg C
Oil: above 85 deg C

The dyno cell was temperature controlled, the 'hot water power loss' is of course due to loss of charge density by heat transfer in the inlet tract.


The issue of oil temp is critical from a number of practical points of view.
Too cold - say below 81 deg C and there is a measurable power loss from drag. With dry sump and later engines with internal-external crescent gear pumps you can run the oil hotter than 85 deg C of course because hopefully the pressure stage of the pump can cope with the bearing bleed-out rate when the oil is going very thin; not so the early Fiat TC (and many other) twin mesh gear pumps used on engines like the one under discussion here, I would not advise that. 85 deg C is certainly not cold as far as power is concerned and is plenty hot enough to evaporate off any moisture - or anything else (like gasoline) that may be in the oil. Also it's important to check the operating temperature of the engine oil seals, if you exceed it they will start to vulcanise.

for what it's worth in this case, in all the tests I did at Warrior I never determined any power increase from going higher than 85-88 deg C.
I say rather vaguely '85-88' of course because as the power comes on the oil temperature tends to rocket, and the thermostatic control won't stabilise unless you give it time to react. These figures are taken from computer-controlled 500rpm step tests with 15 seconds stabilising in between, but even then there is a variation of a degree or so throughout the run, hence average temp figures are cited.

I do not * claim to be the absolute 'authority' on this, other experienced engine builders may have decided on other temperatures for good reason. This is what this forum is for.

GC

*Edited by me later due to unfortunate typo!

[Tico]

Guy, Peter,
Thanks a lot. I have a 13lbs pressurized water system, 72‚ºC termostat, and a biger water pump than original, with the oil 75‚ºC sandwich plate and the oil cooler. In the track water temp has gone up to 95‚ºC and oil 100‚ºC before I backed off.

The thing is I certanly was loosing speed as water temp was higher than 80-85‚ºC. Not only that I felt it but lap times showed it.
As the temp was rising slowly, like 2-3‚ºC every lap, I could conclude with my lap times that the car was slowing down (modestly saying that I am not a profesionl driver, but I wasn't the one slowing, because this races are only 15laps and every other thing of the car was feelling well). Unofrtunadley I haven't been able to dyno test this issue.

I will race next sept and hopely temp is kept down. It is not a pure racing car, but in the roads there in no way to test this, as the temp never goes son high. I will keep you posted.

[Guy Croft]

I would say with some certainty that your problem is too-high underhood and carb intake air temp.
The engine bay just cannot get rid of the heat coming of the exhaust, engine, brakes, radiator, oil cooler..

You should survey the underhood with a temperature gauge after racing and you'll be stunned by how hot everything is, you need to do some serious ducting work. The engine temp you are racing with will take the combustion chamber firmly into the pre-ignition/detonation zone. The power loss, well that is exactly what I was talking about above, it can be huge.

GC

[1969race125]

My 125 used to have overheating issues, which have been solved with a combination of modern radiator cores, heat-wrapped exhaust headers, and a cold air intake which (with the help of a large plate between trumpets and carbs) keeps the intake air nice and cool (see below). The car now runs at around the temperatures Guy recommends, for full race distances.

[Tico]

Thanks for all that info and pictures. I should have sayed that I use a deflector very similar to the one showed in the GC book on a beta cupe for keeping the hot air from the radiators away of the carbs intake. Nevertheless Guy should be right of the underhood high temp, as everything shows very hot when racing (carb filters get like "expanded").
Guy, you say in the other forum to use a deflector under the engine? (did I understand well?), because re-reading the book I don't see any photo or clue how this would work. Is this comun to all betas, or how can it be only in mine?
(I would liked to have placed pics, but I am away from home where I have them). thank you from the tropic!

[Guy Croft]

Do you mean an 'undertray?'

Tico, see good little post at:

http://guy-croft.com/viewtopic.php?t=257

If you don't mean undertray please expand on this.

GC

[Tico]

Guy, re-reading the post you refer to, I realise that you mean avoiding the air coming into the engine bay from underneath for aerodynamichs purposes, a very diferent thing from making it easier for the air to leave the engine bay.

I think I am bringing good flow of hot air into the engine bay thru radiators, but may be the air just can not escape from there and the hole place starts to get to hot. Specially if I have a deflector made form the picture on the book (page 112, pic 10/3) wich holds hot air under the deflector in front of the engine to stop air going up to the carbs. I wonder how this car on the photo run because it doesn't have a bonet, does this has to do with high temp on beta's engine bays?

I think I will try to fabricate a closed filter case like the original one that have the fiats 124, conectet to a hose breathing fresh air, take off the deflector and put the oil rad below the front grille. All this expecting a fresher engine bay

Please if anyone has experience in cooling down a beta, bringing fresh air in and out the engine bay I would appreciate. Regards
Tico

[Greenwood037]

Have you tried an oil cooler? It is my understanding that a drop in oil temperature will also result in a drop in water temperature. You can get an oil thermostat to maintain the oil temprature at the range you are looking for.

Jason Greenwood

[Tico]

Hi,
I wanted to share with some of my experience in bringing down the heat problem during racing a Beta . The underhood temp droped by:

- ReI removed the boots (if this is the right word!) from sides leaving more space to the air to come out of the underhood
- Placing a deflector to force all the air from the front grille to pass thru the water radiator or oil radiator
- I made myself a cold box in aluminium for the filters. (look at the photo), using the stock intake element. Inside it fits 2 filters from weber parts house.

-Finally the intake air temp was controlled moving the battery to the back of the car (still haven't got a photo with this). Better weight distribution aswell!.
All this plus the things sayed before this message, proved to be very effective.

[Tico]

I forgot to show you the car! it is a zagato from the US, I changed pistons to beter compression, ported and blueprinted head, biger valves, cams, lightened and balanced crank, uprated clutch, etc. following the "bible" book. I am sitll working with the distributor as it doesn't give the advance curve desired, carbs for the right jeting, and others.