In reply to mke :
Speedway engineering makes a wonderful selection of sway bars in all sorts of widths and diameters/ wall thickness. Arms in either aluminum or steel Straight or tapered. Plus they wind up costing nearly what my material costs are.
Cassius said:It really isn't hard to fabricate, the hard part is to do the math but even that's not That complicated :) If you have to bend the pipe, just remeber to calculate the pipe length, ot the with between the arms ;)
This one is 30x3mm seamless steelpipe, arms ar 50x50x5mm L-profiles. MR is close to 0,5. Adjustability takes it from low 40 N/mm to mid 60 N/mm, but looking at the swaybar only it should yield about 95N/mm in the softest setting. Still need to pretty-up the arms thou (paint on only for rust protection since the car usually sits a couple of months between tinkering times)
If you could say: "Hey, that's ezipizi!" to building a hoovercraft from a f*cking lawnmower at age 11 with no experience then this is a piece of cake ;)
So no heat treat? That was my biggest concern with just fabbing something
frenchyd said:In reply to mke :
Speedway engineering makes a wonderful selection of sway bars in all sorts of widths and diameters/ wall thickness. Arms in either aluminum or steel Straight or tapered. Plus they wind up costing nearly what my material costs are.
They do look nice......
Remember that a sway bar adjusted with differing arm lengths requires disconnection and careful adjustment of link lengths each time you adjust to prevent changing cross weight. If you do blade style adjusters you just turn the blade. You can even make it cockpit adjustable with no effect on cross weight. Make the bar nearly un flexible, and do the flex entirely on the blade ends.
In reply to mke :
Young's Modulus isn't noticeably affected in the heat treating of steels. So if you weld on a normalized 4130 bar it isn't going to change it's spring constant at all.
In reply to mke :
No, no heat treatment. This is a super simple way of doing a swaybar, as long as one calculates it relatively well first :)
Turner X19 has a point in that adjusting the swaybar is easier with blades. The problem with blades are that they are straight, and that the blades flex making them a tad harder to calculate correctly. But if tuning in the last bit of performance is important, blades are the way to go!
If not, the solution I suggested gives you the opportunity to do curved arms giving you a better MR for the swaybar and thus not forcing you to use as large dimensions on the tube :)
RacetruckRon said:In reply to mke :
Young's Modulus isn't noticeably affected in the heat treating of steels. So if you weld on a normalized 4130 bar it isn't going to change it's spring constant at all.
Yes, my concern was more around yield which would lead to fatigue failure. Obviously it can be designed to stay away from yield but off the top of my head and without doing any actual math, that probably means a bigger bar with longer arms so more weight but maybe more importantly I know the factory bar is heat treated spring steel and mounted about as far from the a-arm as I have frame, so I'm not sure longer arms are an option.
This post has nothing to do with anything really but it is my favorite feature on the car ....the "slow Down" l warning light...I don't know why but I just love it.
Its connected to the cat and is an over temp light.....but how can you not laugh about a "Slow Down" light in a ferrari? I ran a wire to it from the ECU...but haven't decide exactly how I'll use it but I figured low oil pressure of rev limit or something light that....or maybe just to mess with people.
Regarding the antisway bar, the latest episode of Finnegan's Garage on YouTube, they fabricate a new swaybar for Mike's '55 Chevy gasser, using premade splined ends TIG welded to a length of appropriate round tube, so heat treating definitely not required.
https://youtu.be/nB9zz7TaZ2w?t=507
(Swaybar fabrication starts at 22:45, if the link doesn't already go there.)
mke said:This post has nothing to do with anything really but it is my favorite feature on the car ....the "slow Down" l warning light...I don't know why but I just love it.
Its connected to the cat and is an over temp light.....but how can you not laugh about a "Slow Down" light in a ferrari? I ran a wire to it from the ECU...but haven't decide exactly how I'll use it but I figured low oil pressure of rev limit or something light that....or maybe just to mess with people.
My F355 had that too. I replaced 2 sets of cats in 1 year with that car.
I have a 911, which being a much more basic car gives you only a rear view mirror with which you must keep an eye out for the engine departing the vehicle in the form of a fine chaff, should the mood take it to so do.
My X1/9 had the slow down light too. It makes even less sense in a car that is already fairly slow....
Darchangel said:Regarding the antisway bar, the latest episode of Finnegan's Garage on YouTube, they fabricate a new swaybar for Mike's '55 Chevy gasser, using premade splined ends TIG welded to a length of appropriate round tube, so heat treating definitely not required.
https://youtu.be/nB9zz7TaZ2w?t=507
(Swaybar fabrication starts at 22:45, if the link doesn't already go there.)
That had me shakin my head in disbelief until I realized it was the rear of a drag car...the bar is about triple the strength of the mounts and like what the.....drag car. Its job is STOP any and all body roll, no tuning that! no means no :)
I'm still concerned about material strength and fatigue on real antisway bars....I'll make a spread sheet to calculate everything when I get a change and before I make any real plans.
TurnerX19 said:My X1/9 had the slow down light too. It makes even less sense in a car that is already fairly slow....
Ok, that might be funnier than the light in the ferrari.
I was thinking I would tell people "yeah, its required to register any car with over 900hp for street use" :)
... you could hook it to a radar detector.
When I asked about making a sway bar, a machinist friend of mine suggested using 4150 PHT (pre heat treated) steel. You machine two key-ways into the end to attach the swing arms since welding on it would ruin the heat treating.
In reply to BirgerBuilder :
That's where my head was too...something around rc50-55 and 200-250 ksi....a spring. But it looks like a lot of guys are making 60psi tubing work so it must work.
In reply to mke :
Another suggestion. When I was a kid my neighbor had an Offenhauser that threw a rod and almost sawed itself in half. They welded it back together and went back racing.
Top fuel racers will “window” a block when throwing a rod. they might even weld two windows in, more than that they just sell the block to alcohol racers.
The point is they use alcohol when engines have a lot of welding. That’s because alcohol is easier than gas or fuel. The combustion is “softer” even though it makes more power.
The slower flame front chases the piston further down the cylinder than gasoline does.
E85 is pretty much like alcohol except you can buy it at the gas station. And it’s cheap for 104 octane fuel. Sure you’ll need about 60% more but right now it’s selling for around $1.79-$1.89 a gallon while premium is over $3.00 a gallon.
One final point, spill a little alcohol on your hand. Feel how cool it is? Wouldn’t that be a good thing for that hot compressed air from your supercharger?
What about, if coolant temp < 150 degrees F & RPM > 3000 RPM, illuminate Slow Down light? Basically a "don't run it hard until warmed up sufficiently" light. Not sure if MS can do this sort of thing or not. Could be done with a temp sensor, an RPM switch, and the right relay if not.
In reply to frenchyd :
That H-D had welded connecting rods in it for 2 full seasons. It was a destroked sportster lower end with an XR top ends and the choice was 1: spacers under the barrels ot cut the rods...you know just temporary until I get custom one....which took 2 seasons to get to the top of the spending list Steel welds good.
pres589 (djronnebaum) said:What about, if coolant temp < 150 degrees F & RPM > 3000 RPM, illuminate Slow Down light? Basically a "don't run it hard until warmed up sufficiently" light. Not sure if MS can do this sort of thing or not. Could be done with a temp sensor, an RPM switch, and the right relay if not.
Yeah when I wired it in I was thinking of using it like a "check engine" light and on for minor error and flashing for serious stuff but haven't programed that yet. I'm also thinking maybe get the throttle into the action for stuff like low oil pressure to make a limp home mode....again more stuff I haven't programed.
This is an enginelab ecu not an MS so almost anything is possible...I just have to actually do it.
In reply to mke :
Both of the examples I spoke about are aluminum. Offy’s are all aluminum and so are drag racing’s top fuel engine blocks and heads.
My point is that gasoline is really critical about combustion where alcohol isn’t. Plus Alcohol has a massively broader band between too rich and too lean. Gosh, I hope I’m not explaining things you are already familiar with. If so I apologize.
Regarding the “bad stuff” from alcohol, there are two types commonly used as fuel.
METHANOL not available at the fuel pump
Bad! Hard on parts especially aluminum
ETHANOL found in E85
Good! beer, wine, booze, all made from it.
Pretty benign, only bad effect is it will absorb moisture from the air over time. But additives like Staybil help. Since even gasoline has water in it a little is a good thing
Since you are one sensor away from the capability to use Flex fuel it’s a pretty easy change for you.
Just finished reading this, feel like I need to buy you a beer.
In reply to frenchyd :
I never really though about E85....I've never seen it at a station but Google says there are places that sell it....I'll need to think about that.
Curious about the projected >900 HP out of a ~5L '80's engine, even if race gas is used. I don't see room for forced induction. Nitrous?
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