Two new racecars in NZ

I think I mentioned this before, no need to buy expensive brake bleeders (and I have bought a few). Jut get yourself a cap that fits the master cylinder and it is airtight (may be a spare cap), put a hose in it with a foot pump fitting and connect that to your wheel closest to the reservoir. It will bleed everything like a champ. Just be careful when undoing the nipples, don't take the spanner off and be ready to close the nipple otherwise you'll shoot all your brake fluid out in a matter of seconds. And keep an eye on the fluid level in the reservoir so you don't run it dry.

This is the only way I managed to reliably bleed brakes after installing new master cylinders because the air pressure pushes the fluid too quickly for the air bubbles to fight so they get pushed out even form the high spots.

There should be no measurable loss of air pressure in the tyre too because all you draw is a volume equal to the space above the fluid in the reservoir. I put a little plastic irrigation tap in my line so I can turn off the pressure without having to disconnect from the tyre in case I need to top up the reservoir or whatever.
 
bazzamac said:
Hi Franz. re bleeding brakes, the best ever investment I made for bleeding brakes on my 1969 Alpine A110 was buying a pressure bleeder from Motiveproducts.com Hose cap screws straight on to the normal glass R8 brake reservoirs, build up the pressure, undo the bleed screw and bingo brakes are bled without having someone else pumping the brake pedal. Works a treat.
Click to expand...
They look good. Which exact model did you purchase please? And what pressure do you use please?
 
JohnW said:
They look good. Which exact model did you purchase please? And what pressure do you use please?
Click to expand...
Hi John

I have model 0900. Instructions will give you a guide on pressure usage. I usually pump until the needle is vertical. all a question of feel and not overdo the pressure.
 
Hi All,

I had success with the brake bleeding the first time in a long time!! Thanks for all the tips but through the years of battling I have derived my own shortcuts because I'm always alone and then your imagineering really comes in handy.

This is my bleeding cap that goes on the reservoir with a long length of tubing. I use my compressor to supply the air pressure for bleeding. the long tubing allows me to walk with the air gun to all the wheels and opening and closing can always be done under pressure and no air can accidentally slip into the calipers.

thumbnail_IMG_1472.jpg


Then at some stage, while I was having problems, I believed that there was air trapped inside the master cylinder at the far end where the copper pipe gets joined. I thought there would be an air bubble on the top wall of the master where it can't get out because the brake switch hole is in the center, and this bubble sits above this center on the cylinder ceiling. So I imagineered this special tool below to pre-bleed the master in the vice by manually pumping and turning it in all different angles and then gently carrying it to the car and doing the installation.


thumbnail_IMG_1471.jpg

I took the car down the road to check the brakes and I was so sure I heard it knocking/pinking. That is on my car instant death to the head gasket because the standard gasket's fire ring almost pritrudes into the combustion chamber. So I replaced the gasket today but the old one was actually okay. I must be hearing different noises that I'm not used to because of the helmet. So there she is ready for a re=torque and some racing at Hampton Downs on Sunday!!

thumbnail_IMG_1470.jpg


Wish me luck, Frans.
 
You're lucky your master cylinder only has one outlet port. I had to do that once with a four port m/c. After a couple of hours of struggling I was contemplating assembling the entire thing in a bucket of brake fluid like I heard mechanics used to do with diesel injector pumps some time ago.

So I created a contraption like yours. I did however find that at 6 bars most m/c caps leak (not really a problem as long as there is enough air pressure retained) and also the entire volume of fluid can shoot out of the brake system in a flash. Did the trick though (no pressure on my m/c switch probably worked in my favour). Not that I wish to do it again.
 
Fill the air space in the pressure switch with a dob of rubber grease.
 
Always curious about this. My old 1550 built by Salv, ran 29 deg max, so was a pretty hot engine, on the Dyno it made a tiny bit more at 31, but was straying into Det, so it was left at 29, by the tester, it was 11.8:1
My 1700 built by me is not quite as good, tested by the same guy it ended up at 32 deg, proving to me that the compression must be just a touch lower, although I was aiming at the same figure, proving I'm not as good as Salv.
Interestingly the 5G motor does not reach max advance until 5000 rpm, basically it has a fairly weak initial spring which puts on advance early, then a fairly stiff secondary, which needs a lot of rpm to get it to max.
The 1400 is a different story. It has a low compression ratio around 10:1 max as I was not Skimming a lot of material off a really good head. This means it doesn't det, but if you put the timing too advanced it works as a rev limiter (wont go past 7k) having it late really costs you in the mid range, when it was tested 36 deg was the maximum setting for it.
This always fascinates me, the combination of Design, mixture strength / throttle position, burn time, rpm,temperature / ambient temperature. Our little motors always need all the help they can get.
 
dauphproto said:
Always curious about this. My old 1550 built by Salv, ran 29 deg max, so was a pretty hot engine, on the Dyno it made a tiny bit more at 31, but was straying into Det, so it was left at 29, by the tester, it was 11.8:1
My 1700 built by me is not quite as good, tested by the same guy it ended up at 32 deg, proving to me that the compression must be just a touch lower, although I was aiming at the same figure, proving I'm not as good as Salv.
Interestingly the 5G motor does not reach max advance until 5000 rpm, basically it has a fairly weak initial spring which puts on advance early, then a fairly stiff secondary, which needs a lot of rpm to get it to max.
The 1400 is a different story. It has a low compression ratio around 10:1 max as I was not Skimming a lot of material off a really good head. This means it doesn't det, but if you put the timing too advanced it works as a rev limiter (wont go past 7k) having it late really costs you in the mid range, when it was tested 36 deg was the maximum setting for it.
This always fascinates me, the combination of Design, mixture strength / throttle position, burn time, rpm,temperature / ambient temperature. Our little motors always need all the help they can get.
Click to expand...
Have you tried a 123 TUNE, out of interest? Then you can drag and click your curve on screen. I think the TUNE+ is wireless connected so you can check while driving the car (passenger needed...).

Limited to 7K eh? My R8 with an 8S head and the rest standard runs out of breath around 5K-5.5K.
 
Thanks for your input #dauphproto. I’ll decrease the timing to 30 degrees for safety sake.
Those figures are just a way of my thinking. I have never had the car on a dyno and everything was done by feeling. I am lucky as I am running the Megajolt ignition and I can change it in an instant. Most time consuming thing is to fire the laptop up!
I might try to drop the shift light a little to help the engine and see how much the laptimes increase if any at all. Shift light at the moment is at 7400 but I don’t know if It is still making power at that rpm. It is definitely pulling strong at that point in the lower gears.
Any additional info would be welcome.
Frans.
 
  • Like
Reactions: COL
The great thing about it being easy to adjust is that you can experiment easily enough, if you work on the basis of 32 deg being the safe limit, you can back off a degree at a time and see if you can feel any difference or see it on the laptimes.
This is easier to say than do, but does it pull from 6-7k faster than from 5-6 etc. if it does then you use it. You say it pulls strong up there, and after all these years you will know/feel when it's over the top.
That was the main reason I started to have all my engines tested, it removed all doubt as to whether it was the best it could be, or not in that set up. Plus in my case it was being done by a guy with huge experience in building and testing Race Engines.
I would think that in the case of the Gordini engine, with hemispherical chamber and domed pistons, something which is not brilliant for mixing at low to moderate rpm, due to the strange shaped combustion chamber it produces, but improves at high rpm. The Demon Tweak for this is Gordini's masked plug, which starts the flame front in 2 different directions at the same time reducing burn time, and detonation. Meaning the total advance required is lower perhaps
Interesting to see how this is accomplished on the 5 Gordini Head which is an early example of a lean burn head being half a hemi with a ramp in one side and the plug in the other, the ramp forcing all of the mixture to the plug side to promote good mixing and fast burn time.
In answer to John W. the 123 thing is great for trying to wring some added power and economy out of standard motors, by being able to try different curves, but makes little or no difference to a race engine with an optimised inlet and exhaust systems, they are by their nature much more efficient at doing their jobs than standard parts. If it had the ability to read manifold vacuum/ throttle position it would be more of a benefit, but would not add any more outright power. That had already been found on the dyno. You work backwards you find the optimum Full power full load full rpm settings and wherever the engine idles is, wherever it idles. The potential benefits on standard low revving engines are greater
My 8G had getting on for 175 bhp max, but would return 35mpg on a run at legal speed. I always laugh inside when people come up for a look and see the huge carbs and say ` it must be thirsty' Flat out yes, cruising No it's a much more efficient unit, so makes best use of what it's got. It has no need for vacuum advance, as the part throttle cylinder filling is much more than on a standard engine, so you don't need to add another 6-7 degrees of advance to improve the economy. It does not need a cold start as there is not the level of fuel drop out onto manifold floor/port walls that a standard engine has until the head/manifold are warmed up, yes it's a bit uneven for the first 20-30 seconds, but that's it.
I've been having fun teaching my son to listen to the engine, as far as throttle control goes. He know about throttle control from online racing, esp. in slippery conditions, however it was funny to watch him in the car, as he had no concept of the fact that old analogue race engines have to be driven correctly to get the best from them and it is a level of subtlety he has no experience of. It was quite funny to watch him press too hard too early and lose time as a result. Possibly I should have adjusted the throttle linkage to only give half throttle until he began to find his feet. It's hard to describe cornering to someone who has never done it in anger, but I'll have a go. Basically you are going what feels like just too fast, so you squeeze down steadily waiting for the limit of adhesion to be exceeded, sometimes it becomes a series of squeezes as you nerve won't allow you to do more, lifting off isn't really an option as it causes a similar set of problems in reverse. Naturally all of this has happened in a very short space of time........
Good Luck Frans. I hope you have good incident free racing....
 
The weekend’s racing. It was bitter-sweet again. I don’t seem to get a good all-round race. But who cares it was great fun.

We were first to go out for qualifying and it was good. I qualified 9th on the grid out of 29 cars.

This is a list of cars and how they qualified. There are some late entries that I couldn’t place but you can get a general overview from the list with the grid positions in RED.

qual.jpg


However, that qualifying result helped me nothing at all. I was busy reading the program when our race convenor came rushing up to me “Aren’t you racing?” I then realised that I had to be on the grid already. So I got the helmet and HANS device on, harness and gloves while leaving the pit area but I was too late to join the grid and I had to start from the pit lane! The race ended quite well as I had a new experience making up positions with plenty of traffic coming up. 8 lap race and I ended 15th. I earned the “Turkey of the Day” award at prize giving for this little mishap of mine.

turk.jpg


Then in time for race 2, a handicap race, I managed to win from 13th on the grid. That was some consolation that made me feel better.

In time again for race 3, a long 12 lap race I got a 6th place. It would have been 8th but 2 BMWs pushed past me and out braked themselves at the following hairpin where they took themselves out. Still right behind them I avoided the carnage and took their places for myself.

That ended the day with the car not missing a beat and the only corrective work I had to do was to reduce the bias to the rear brakes as the tail-end was a little loose and I had 2 scary slips when the rears locked up and I had to do some corrective handwork to save it.

I have some footage on the camera and will post it when I have edited it.

Regards, Frans.
 
dauphproto said:
The great thing about it being easy to adjust is that you can experiment easily enough, if you work on the basis of 32 deg being the safe limit, you can back off a degree at a time and see if you can feel any difference or see it on the laptimes.
This is easier to say than do, but does it pull from 6-7k faster than from 5-6 etc. if it does then you use it. You say it pulls strong up there, and after all these years you will know/feel when it's over the top.
That was the main reason I started to have all my engines tested, it removed all doubt as to whether it was the best it could be, or not in that set up. Plus in my case it was being done by a guy with huge experience in building and testing Race Engines.
I would think that in the case of the Gordini engine, with hemispherical chamber and domed pistons, something which is not brilliant for mixing at low to moderate rpm, due to the strange shaped combustion chamber it produces, but improves at high rpm. The Demon Tweak for this is Gordini's masked plug, which starts the flame front in 2 different directions at the same time reducing burn time, and detonation. Meaning the total advance required is lower perhaps
Interesting to see how this is accomplished on the 5 Gordini Head which is an early example of a lean burn head being half a hemi with a ramp in one side and the plug in the other, the ramp forcing all of the mixture to the plug side to promote good mixing and fast burn time.
In answer to John W. the 123 thing is great for trying to wring some added power and economy out of standard motors, by being able to try different curves, but makes little or no difference to a race engine with an optimised inlet and exhaust systems, they are by their nature much more efficient at doing their jobs than standard parts. If it had the ability to read manifold vacuum/ throttle position it would be more of a benefit, but would not add any more outright power. That had already been found on the dyno. You work backwards you find the optimum Full power full load full rpm settings and wherever the engine idles is, wherever it idles. The potential benefits on standard low revving engines are greater
My 8G had getting on for 175 bhp max, but would return 35mpg on a run at legal speed. I always laugh inside when people come up for a look and see the huge carbs and say ` it must be thirsty' Flat out yes, cruising No it's a much more efficient unit, so makes best use of what it's got. It has no need for vacuum advance, as the part throttle cylinder filling is much more than on a standard engine, so you don't need to add another 6-7 degrees of advance to improve the economy. It does not need a cold start as there is not the level of fuel drop out onto manifold floor/port walls that a standard engine has until the head/manifold are warmed up, yes it's a bit uneven for the first 20-30 seconds, but that's it.
I've been having fun teaching my son to listen to the engine, as far as throttle control goes. He know about throttle control from online racing, esp. in slippery conditions, however it was funny to watch him in the car, as he had no concept of the fact that old analogue race engines have to be driven correctly to get the best from them and it is a level of subtlety he has no experience of. It was quite funny to watch him press too hard too early and lose time as a result. Possibly I should have adjusted the throttle linkage to only give half throttle until he began to find his feet. It's hard to describe cornering to someone who has never done it in anger, but I'll have a go. Basically you are going what feels like just too fast, so you squeeze down steadily waiting for the limit of adhesion to be exceeded, sometimes it becomes a series of squeezes as you nerve won't allow you to do more, lifting off isn't really an option as it causes a similar set of problems in reverse. Naturally all of this has happened in a very short space of time........
Good Luck Frans. I hope you have good incident free racing....
Click to expand...
Thanks for that great explanatory post. What I like about the 123 is partly not messing about with points etc any more and partly definitely a better spark - the car has never started so well in 50 years! I can't detect the slightest improvement in performance and haven't bothered doing much with the curves.
 
bazzamac said:
Interesting you are the only Renaut running! Surely there are some others Franz.
Click to expand...

@bazzamac, the other Renault at the track was my 21T tow vehicle!

@dauphproto some light-hearted consolation trophy, wish it was $10 000 prize money!!;)

@Shoji and the oldest driver as well. At least there is another guy that shares the age group with me. Both of us are 71 years young.

Frans
 
I am curious Frans, why are there cars with engine capacities greater than 2.0 lit, racing in the Group A 0-2000 class (although I see they are really not competitive based on where they finished)?
Or is there another measure that is not immediately obvious - power/weight?

Here (MSCA sprint series) there are 2 classes for 0-2000cc cars - pre and post 1985 (classic vs modern).
 
You must log in or register to reply here.
Top