Dutch Sierra Cosworth 4x4 - home made power measurement
25-10-2017, 06:57 AM
#122
Although I haven't driven the car on track with the new front arb I don't have the feeling it will make the handling exactly how I would like it. In the movie where the Opel Speedster is behind me it's easy to see that the cossie is rolling quite a lot in corners. The 29 mm front arb is about 15% stiffer than the 28 mm so it should help a bit countering the roll. And with the stiffer front arb I can also run a stiffer rear arb while keeping the balance of the car the same, so that should help a little more.
But the rolling in itself is not that bad, once settled in the corner the grip is quite good. But when turning into corners the car really needs some time to settle. The car also feels a bit like it's not rolling horizontally, but more like the front dives a bit and the car is leaning a lot on the outside front tyre. i think you can also see it a bit on a screenshot from the movie.
With the lower ride height the front roll center is also lowered and I have the feeling that is at least partly the cause of the leaning on the outside front tyre. The lower roll centre will also cause more body roll and a less direct steering feel.
So it would be nice to get the roll centre back to where it originally was. One of the things I had been thinking of for a while was extending the pins on the TCA ball joints. So I've cut a TCA from a standard Sierra open to see how the ball joint is made and whether something can be done with that. On the bottom of the TCA there is some kind of 'lid' that is pressed closed. I've ground the edge off so I could see what's fitted inside. The steel pin has a metal ball at the bottom that is turning inside plastic bush using lots of grease.
While searching on the internet I found someone you replaces the standard ball joints in Escort mk1/mk2 arms with spherical bearings to make them last longer and also to be able to replace them, as I believe it is difficult to find Escort mk1/mk2 arms with good ball joints. The spherical bearings he uses are from SKF and have a 35 mm outer diameter. The outer diameter of the arm I ground open is just a bit more than 40 mm. So with a 35 mm bearing inside the wall thickness would only be about 2.5 mm, which I find a little small for such a thing.
Since the Cosworth arms are a bit different than standard Sierra arms I checked the diameter of the ball joint area on the Cosworth arms and those are 46 mm. With 46 mm there is a wall thickness of 5.5 mm left when the 35 mm bearing is fitted, so that should be fine. But I didn't have a set of worn Cosworth arms to use and I find it a shame to use orignal arms that are still good. After some checks I found that the arms from a Granada mk3 (Scorpio in Holland) also have the larger diameter of 46 mm.
I have cut a set of aftermarket Granada arms open. The ball joint and plastic bush in these arms was even smaller than the one in the 40 mm Sierra arm. That will explain why the ball joints on some aftermarket arms wear out much quicker than on OEM arms. But for what I have mind this doesn't matter anyway, there's just a little bit more meat to mill out.
But the rolling in itself is not that bad, once settled in the corner the grip is quite good. But when turning into corners the car really needs some time to settle. The car also feels a bit like it's not rolling horizontally, but more like the front dives a bit and the car is leaning a lot on the outside front tyre. i think you can also see it a bit on a screenshot from the movie.
With the lower ride height the front roll center is also lowered and I have the feeling that is at least partly the cause of the leaning on the outside front tyre. The lower roll centre will also cause more body roll and a less direct steering feel.
So it would be nice to get the roll centre back to where it originally was. One of the things I had been thinking of for a while was extending the pins on the TCA ball joints. So I've cut a TCA from a standard Sierra open to see how the ball joint is made and whether something can be done with that. On the bottom of the TCA there is some kind of 'lid' that is pressed closed. I've ground the edge off so I could see what's fitted inside. The steel pin has a metal ball at the bottom that is turning inside plastic bush using lots of grease.
While searching on the internet I found someone you replaces the standard ball joints in Escort mk1/mk2 arms with spherical bearings to make them last longer and also to be able to replace them, as I believe it is difficult to find Escort mk1/mk2 arms with good ball joints. The spherical bearings he uses are from SKF and have a 35 mm outer diameter. The outer diameter of the arm I ground open is just a bit more than 40 mm. So with a 35 mm bearing inside the wall thickness would only be about 2.5 mm, which I find a little small for such a thing.
Since the Cosworth arms are a bit different than standard Sierra arms I checked the diameter of the ball joint area on the Cosworth arms and those are 46 mm. With 46 mm there is a wall thickness of 5.5 mm left when the 35 mm bearing is fitted, so that should be fine. But I didn't have a set of worn Cosworth arms to use and I find it a shame to use orignal arms that are still good. After some checks I found that the arms from a Granada mk3 (Scorpio in Holland) also have the larger diameter of 46 mm.
I have cut a set of aftermarket Granada arms open. The ball joint and plastic bush in these arms was even smaller than the one in the 40 mm Sierra arm. That will explain why the ball joints on some aftermarket arms wear out much quicker than on OEM arms. But for what I have mind this doesn't matter anyway, there's just a little bit more meat to mill out.
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Marc sierra (29-10-2017)
29-10-2017, 02:49 PM
#124
Thanks! 
The rear beam has really been an improvement in the handling! The front setup with the combined compression struts and arb was less good. It's either the strut of the arb taking up the force from braking. When putting extra struts like these on the purpose is that the struts should take the force from braking. But since they connect a bit lower to the chassis than the arb the anti dive is changed and the car dove a lot more during braking. I've removed the struts now and I like it a lot better, during braking the car dives much less.
The rear beam has really been an improvement in the handling! The front setup with the combined compression struts and arb was less good. It's either the strut of the arb taking up the force from braking. When putting extra struts like these on the purpose is that the struts should take the force from braking. But since they connect a bit lower to the chassis than the arb the anti dive is changed and the car dove a lot more during braking. I've removed the struts now and I like it a lot better, during braking the car dives much less.
07-11-2017, 01:34 PM
#125
The spherical bearings from SKF that will go in the TCA are also in.
It's actually a nice thing the original ball joints in these arms were smaller than normal. It definately leaves enough meat for the new bearing to be machined nice and tight inside the arm.
It's actually a nice thing the original ball joints in these arms were smaller than normal. It definately leaves enough meat for the new bearing to be machined nice and tight inside the arm.
30-11-2017, 11:35 AM
#127
I had the guy from the UK who converts the Escort mk1/mk2 arms also convert my arms. I have given him the info for the ball joint pins, as the shape is different than the Escort and they are now also longer than standard. He also made a set of tie rod ends, which are also longer and adjustable to correct the bump steer that would be created by the longer ball joint pins on the TCAs.
The ball joint pin only has the cut out on one side, instead of all around like the original pin. It makes fitting them a bit less easy, but it will be stronger.
The spherical bearing is held in place from the bottom by a circlip.
I used some loctite on the bolt to hold the ball joint pin on the spherical bearing. I don't want to experience that coming off.
And finally the lengthened tie rod end with some spacers to adjust the length to get the bump steer as good as possible.
But since it's almost winter it will probably take a while before everything will be fitted...
The ball joint pin only has the cut out on one side, instead of all around like the original pin. It makes fitting them a bit less easy, but it will be stronger.
The spherical bearing is held in place from the bottom by a circlip.
I used some loctite on the bolt to hold the ball joint pin on the spherical bearing. I don't want to experience that coming off.
And finally the lengthened tie rod end with some spacers to adjust the length to get the bump steer as good as possible.
But since it's almost winter it will probably take a while before everything will be fitted...
30-11-2017, 04:06 PM
#128
Very nice job with the tca:s and steering arms. Wouldnt mind a set of my own 
How much is the tca joint spaced? I also need to sort out my front rollcenter. As it is now my car handles pretty good but the coilovers are at their highest setting so the car looks a bit funny. Almost like a offroader
// Jimmy
How much is the tca joint spaced? I also need to sort out my front rollcenter. As it is now my car handles pretty good but the coilovers are at their highest setting so the car looks a bit funny. Almost like a offroader // Jimmy
Last edited by Jimmy86; 30-11-2017 at 04:09 PM.
01-12-2017, 02:40 PM
#132
10K+ Poster!!
Mk motorsport do these for Ł380 including the proper bearings. I have posted these pics somewhere else I think.<br/>
01-12-2017, 03:22 PM
#134
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03-12-2017, 06:52 AM
#135
So then its 460 in total from MK. And do they MK ones have a tapered fit for the tie rod ends? As you can also get tie tod ends with straight bolts from Compbrake, but then you need to drill your knuckle to accept the bolt. With my kit nothing has to be changed to the knuckles. And the outer ball joint is sealed from the top and bottom on mine.
Besides, I dont know why it is relevant that MK does these anyway. I was working on having them made before the first proto from MK was shown.
Besides, I dont know why it is relevant that MK does these anyway. I was working on having them made before the first proto from MK was shown.
03-12-2017, 08:44 AM
#136
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I was only trying to help with what is available.
26-02-2018, 02:49 PM
#138
I have been wondering for a while where the front roll centre on the 4x4 would be located. For the 3dr and 2wd sapph there is some info available where it is when the car is on standard ride height. But for the 4x4 there is no info available. And apart from that I also wanted to know where it is right now, with the Ahmed Bayjoo springs fitted.
So I decided to do some measurements to be able to calculate where it should be. I put in all the measurements in Excel and according to the calculations the roll centre would be 15.6 mm above the ground.
I also re-did the calculation with the longer ball joint pins to see how much the roll centre would increase from that. I got a value of 50.3 mm, which I expect should be close to standard. But it is still lower than the 2wd Sapph, which had 70 mm from standard.
So I decided to do some measurements to be able to calculate where it should be. I put in all the measurements in Excel and according to the calculations the roll centre would be 15.6 mm above the ground.
I also re-did the calculation with the longer ball joint pins to see how much the roll centre would increase from that. I got a value of 50.3 mm, which I expect should be close to standard. But it is still lower than the 2wd Sapph, which had 70 mm from standard.
26-02-2018, 02:55 PM
#139
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Can you or anyone comment how these sorts of measurements would affect the handling and other traits?
I find this stuff quite interesting
I find this stuff quite interesting
26-02-2018, 03:32 PM
#141
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26-02-2018, 04:00 PM
#142
The roll centre is a virtual point around which the car rolls during cornering. The car itself can be seen as mass in a single point, the centre of gravity. The lateral acceleration during cornering acts on the centre of gravity and creates an outward force.
Normally the centre of gravity will be located above the roll centre and the outward force together with the distance between the centre of gravity and roll centre becomes a roll couple that makes the car roll around the roll centre.
If the centre of gravity and roll centre are in the exact same position the distance is 0, so the roll couple is also 0, which means that in this situation the car will not roll in corners. If the roll centre is higher than the centre of gravity the car would roll the other way.
But having the roll centre high is not necessarily a good thing. It makes the car twitchy and unstable (hence the complaints on the original 3dr). Also the lack of body roll makes it more difficult to feel the limits of the car.
And what is also important is that the roll centre is not a static thing. When the suspension arms move during cornering the roll centre will also move. A roll centre that moves a lot also gives a strange feeling to the driver. So I think it's best to have the roll centre in such a way that it doesn't move much. The best way for that is (on a McPherson setup) having the arms going slightly down from the cross member to the knuckles.
Normally the centre of gravity will be located above the roll centre and the outward force together with the distance between the centre of gravity and roll centre becomes a roll couple that makes the car roll around the roll centre.
If the centre of gravity and roll centre are in the exact same position the distance is 0, so the roll couple is also 0, which means that in this situation the car will not roll in corners. If the roll centre is higher than the centre of gravity the car would roll the other way.
But having the roll centre high is not necessarily a good thing. It makes the car twitchy and unstable (hence the complaints on the original 3dr). Also the lack of body roll makes it more difficult to feel the limits of the car.
And what is also important is that the roll centre is not a static thing. When the suspension arms move during cornering the roll centre will also move. A roll centre that moves a lot also gives a strange feeling to the driver. So I think it's best to have the roll centre in such a way that it doesn't move much. The best way for that is (on a McPherson setup) having the arms going slightly down from the cross member to the knuckles.
The following 2 users liked this post by Marc sierra:
Caddyshack (26-02-2018),
Mark V8 (26-02-2018)
26-02-2018, 07:27 PM
#143
10K+ Poster!!
Good explanation, thank you
26-02-2018, 07:29 PM
#144
10K+ Poster!!
That last bit rings very true, whenever my tca's became inverted the car was terrible, my new floor and Wrc crossmember will correct this even when the car is set low
26-02-2018, 07:37 PM
#145
With the TCAs going down towards the knuckles the camber gain through the suspension travel is better. So the outer wheel will gain more negative camber and the inner wheel will loose more camber, which puts them more straight up, giving more front end grip.
On the other hand the less body roll caused by the front suspension will give the rear more grip, basically the same as fitting a stiffer arb to the front. So in theory getting the front roll centre back where it used to be should give more front and more rear end grip.
On the other hand the less body roll caused by the front suspension will give the rear more grip, basically the same as fitting a stiffer arb to the front. So in theory getting the front roll centre back where it used to be should give more front and more rear end grip.
27-02-2018, 08:02 PM
#146
Good job on the front end, Sierras need that mod to behave on the track when lowered. Marc have u measured the rear rollcenterhieght with your modified beam? Looked for that info all over the net but cant find anyone who have checked it. Going to do my own rear beam in a couple of weeks and thats a good opportunity to change the rollcenter. I'll probably try to move up my inner rear trailing arm mount abit to raise it.
// Jimmy
// Jimmy
28-02-2018, 07:09 AM
#147
Yes I have also done some measurements and calculations for the rear roll centre. With the 6 degree beam and my current ride height it can to approximately 3.8 cm. The calculations also show the rear camber and toe for a given bump/droop of the wheel.
With a normal beam the roll centre would be roughly 3 times higher. The reason for that is that a normal beam has a sweep angle of 18 degrees, which is 3 times more than the 6 degree beam. Raising the rear roll centre could in theory be done by moving the inner pivot point of the arms up, but in practice there is no room so you would have to cut a hole in the floor. Besides, I'm not sure if there would be any benefit from raising the rear roll centre.
With a normal beam the roll centre would be roughly 3 times higher. The reason for that is that a normal beam has a sweep angle of 18 degrees, which is 3 times more than the 6 degree beam. Raising the rear roll centre could in theory be done by moving the inner pivot point of the arms up, but in practice there is no room so you would have to cut a hole in the floor. Besides, I'm not sure if there would be any benefit from raising the rear roll centre.
28-02-2018, 09:13 AM
#148
Yes I have also done some measurements and calculations for the rear roll centre. With the 6 degree beam and my current ride height it can to approximately 3.8 cm. The calculations also show the rear camber and toe for a given bump/droop of the wheel.
With a normal beam the roll centre would be roughly 3 times higher. The reason for that is that a normal beam has a sweep angle of 18 degrees, which is 3 times more than the 6 degree beam. Raising the rear roll centre could in theory be done by moving the inner pivot point of the arms up, but in practice there is no room so you would have to cut a hole in the floor. Besides, I'm not sure if there would be any benefit from raising the rear roll centre.
With a normal beam the roll centre would be roughly 3 times higher. The reason for that is that a normal beam has a sweep angle of 18 degrees, which is 3 times more than the 6 degree beam. Raising the rear roll centre could in theory be done by moving the inner pivot point of the arms up, but in practice there is no room so you would have to cut a hole in the floor. Besides, I'm not sure if there would be any benefit from raising the rear roll centre.
I havent actually checked if there is room between the mount and the floorpan and I'm not going to cut in it so I guess I'll leave it be then. As i understand it u want a higher rear rollcenter than u have in the front. (rollaxle should tilt down from the rear end to the front.) This because the rear end needs some "time" to react to what the front end is doing during turn-in. Otherwise the rear end "lags behind". This in turn can create understeer thou....
I'm already running very stiff springs and would as u are doing try to limit the roll with the stiffness I have.
I finaly sorted a set of 3dr hubs and going to run Scorpio mk1 Cosworth (granada for u guys on the island) arb along with a quaife ATB in the 6 degree beem.
Hope the car will be alot better on the tracks this summer. Guess I'll have to update my own thread soon since I have done quite alot since last update.
// Jimmy
28-02-2018, 01:10 PM
#149
It is indeed said that most of the times you want a higher roll centre on the rear than of the front. It is said that on the front it should be about 3/4 of the rear.
An interesting text on a forum I found about roll centres:
I believe that during cornering the front roll centre on a Sierra will drop, due to the angle of the TCA changing.
On the rear I believe the roll centre will go up during cornering. When the body leans in the corner, the outer pivot of the outer arm moves down more than the inner pivot of the outer arm. This means the instant centre moves up so the roll centre also moves up.
So during cornering the rear roll centre might actually still be higher than the front, although stationary it is the other way around.
An interesting text on a forum I found about roll centres:
The front part of the chassis is forced to hinge on the front RC, and the rear part is forced to hinge on the rear RC. If the chassis is rigid, it will be forced to hinge on the axis that connects both RCs , that axis is called the roll axis ,The position of the roll axis relative to the cars CG tells a lot about the cornering power of the car; it predicts how the car will react when taking a turn. If the roll axis is angled down towards the front,( Rear Roll Centre Higher that the Front RC ) the front will roll deeper into its suspension travel than the rear, giving the car a 'nose down' attitude in the corner. Because the rear roll moment is small relative to the front, the rear won't roll very far; hence the chassis will stay close to ride height. Note that with a car with very little negative suspension travel (droop) the chassis will drop more efficiently when the car leans over. With the nose of the car low and the back up high, a bigger percentage of the cars weight will be supported by the front tires, more tire pressure means more grip, so the car will have a lot of grip in the front, making it oversteer. A roll axis that is angled down towards the rear will promote understeer. Remember that the position of the roll centers is a dynamic condition , so the roll axis can actually tilt when the car goes through bumps or takes a corner, so it's possible for a car to understeer when entering the corner, when chassis roll is less pronounced, and oversteer in the middle of the corner because the front RC has dropped down a lot, In terms of car handling, this means that the end with highest RC has the most grip initially, when turning in, or exiting the corner, and that the end with the lowest RC when the chassis is rolled will have the most grip in the middle of the corner. a very high roll center in the front will make the car turn in very aggressively, but understeer in the middle of the corner. It's nice if you like an aggressive car you can 'throw' into the corners, but I doubt it's the fastest way round the track. Conversely, if the rear roll center is set very high, the car will turn in very gently, and possibly oversteer after that.
I believe that during cornering the front roll centre on a Sierra will drop, due to the angle of the TCA changing.
On the rear I believe the roll centre will go up during cornering. When the body leans in the corner, the outer pivot of the outer arm moves down more than the inner pivot of the outer arm. This means the instant centre moves up so the roll centre also moves up.
So during cornering the rear roll centre might actually still be higher than the front, although stationary it is the other way around.
28-02-2018, 03:25 PM
#150
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Whilst we are on this handling malarky....
In my 4x4 Pug I can go round a tight bend and feel a slight snatch / pull at the rear, I have assued this is 1 or 2 things a) the limit slip diff taking up on the rear (uprated weir kit in supra or b) the ackermann being out and causing a drag? I have experienced this before on a Z3M Coupe that had an LSD and I am assuming it is just the diff running out of twist.
In my 4x4 Pug I can go round a tight bend and feel a slight snatch / pull at the rear, I have assued this is 1 or 2 things a) the limit slip diff taking up on the rear (uprated weir kit in supra or b) the ackermann being out and causing a drag? I have experienced this before on a Z3M Coupe that had an LSD and I am assuming it is just the diff running out of twist.
28-02-2018, 03:45 PM
#151
I think if it would be the ackermann being out it would be the front that is dragging. So my guess would be the lsd in the rear, although it would have to be a tight lsd to do that on a dry road. I've experienced similar on a drift car with a welded diff.
28-02-2018, 03:50 PM
#152
I'm already running very stiff springs and would as u are doing try to limit the roll with the stiffness I have.
I finaly sorted a set of 3dr hubs and going to run Scorpio mk1 Cosworth (granada for u guys on the island) arb along with a quaife ATB in the 6 degree beem.
Hope the car will be alot better on the tracks this summer. Guess I'll have to update my own thread soon since I have done quite alot since last update.
// Jimmy
I finaly sorted a set of 3dr hubs and going to run Scorpio mk1 Cosworth (granada for u guys on the island) arb along with a quaife ATB in the 6 degree beem.
Hope the car will be alot better on the tracks this summer. Guess I'll have to update my own thread soon since I have done quite alot since last update.
// Jimmy
Which Scorpio mk1 cosworth arb do you mean, the front or the rear? The front one would be an upgrade for a Sierra since it's 29 mm thick, but should be used with longer TCAs to give more camber. The rear one is an 18 mm one, just like on the Sapph 4x4. So in that case there are better (thicker) ones to use.
28-02-2018, 04:39 PM
#153
10K+ Poster!!
It isn't a skidding of the tyre, just a feeling of a pull, like a very mild roll oversteer or tightening of the line in the bend, I can put in more power and it doesn't slide, it just feels like a tug. I noticed very similar on my mates 4x4 truck on the road, turn a tight turning and it's like pulling up the hand brake gradually.
28-02-2018, 06:33 PM
#154
I have also read the forum post u quoted. As i understand it the 6 degree beam wont change ur rollcenter. Just get rid of some of your bumpsteer. U are probably better than me on the geometry but as I understand it this is how u measure your rollcenter on a semi-trailing rear suspension
That means u only move ur rollcenter forward since ur not changing the pivot axle angle up/down. Or am I totaly retarded? Thats why I wanted to move mine up abit.
As for my arb it is the front 29.3mm one. Will be put togheter with my 3dr hubs along with adjustable tca:s so the width problem wont be any problem I hope.
Caddyshack:
Is it a 1 way, 1.5 way or 2 way lsd? As said it is probably ur lsd ur feeling when u make a tight turn.
Here's a good video explaining it if u dont know.
Edit: Sorry for making a mess of your thread Marc
// Jimmy
That means u only move ur rollcenter forward since ur not changing the pivot axle angle up/down. Or am I totaly retarded?
Thats why I wanted to move mine up abit.As for my arb it is the front 29.3mm one. Will be put togheter with my 3dr hubs along with adjustable tca:s so the width problem wont be any problem I hope.
Caddyshack:
Is it a 1 way, 1.5 way or 2 way lsd? As said it is probably ur lsd ur feeling when u make a tight turn.
Here's a good video explaining it if u dont know.
Edit: Sorry for making a mess of your thread Marc
// Jimmy
Last edited by Jimmy86; 28-02-2018 at 06:38 PM.
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Caddyshack (28-02-2018)
28-02-2018, 06:37 PM
#155
10K+ Poster!!
I actually don't know what the supra diff with weir kit is (not that weir spring would change the number), I do think it is the diff I am feeling
28-02-2018, 08:08 PM
#156
I have also read the forum post u quoted. As i understand it the 6 degree beam wont change ur rollcenter. Just get rid of some of your bumpsteer. U are probably better than me on the geometry but as I understand it this is how u measure your rollcenter on a semi-trailing rear suspension
That means u only move ur rollcenter forward since ur not changing the pivot axle angle up/down. Or am I totaly retarded? Thats why I wanted to move mine up abit.
That means u only move ur rollcenter forward since ur not changing the pivot axle angle up/down. Or am I totaly retarded?
Thats why I wanted to move mine up abit.The picture you showed how to determine the rear roll centre is correct, but I'm not sure whether you interpreted it correctly. In the upper picture the instant centre is where the 2 dashed lines intersect. But in that picture you cannot see how high the instant centre is. In the bottom picture you see the instant centre from a front view, where the height is visible. Where the line from the tyre centre to the instant centre crosses the centre line from the car is where the roll centre is.
The roll centre is always exactly between the two wheels, it cannot move forward or backward.
On a 6 degree beam the instant centre is much further away than on a standard (18 degree beam) because the angle of the upper dashed line is much smaller.
01-03-2018, 02:46 PM
#157
Still dont get it really but I'm pretty sure u know what ur talking about. In the end I still belive the 6 degree beam will do a ton for the handling and looking forward to have mine made.
Looking forward to seeing ur new bits mounted and tested! I hope it will turn out nicely on how ur car behave when driven hard.
// Jimmy
Looking forward to seeing ur new bits mounted and tested! I hope it will turn out nicely on how ur car behave when driven hard.
// Jimmy
01-03-2018, 04:37 PM
#158
10K+ Poster!!
Still dont get it really but I'm pretty sure u know what ur talking about. In the end I still belive the 6 degree beam will do a ton for the handling and looking forward to have mine made.
Looking forward to seeing ur new bits mounted and tested! I hope it will turn out nicely on how ur car behave when driven hard.
// Jimmy
Looking forward to seeing ur new bits mounted and tested! I hope it will turn out nicely on how ur car behave when driven hard.
// Jimmy
01-03-2018, 06:07 PM
#159
The 6 degree beam definately does a lot for the handling. It cured a lot of understeer on my 4x4. And science also says it's a good mod. On a standard beam there is a lot change in the toe and camber over the suspension travel. The toe change is what is causing the understeer.
I don't think it's a problem that the rear roll centre is lower with a 6 degree beam.
Ford had already thought of a beam with a smaller sweep angle when they made the RS500. It had special brackets mounted on the subframe to homologate the moved inner pivots for racing. The race version of the RS500 had sweep angle of 8 to 9 degrees, which was the maximum they could achieve within the rules.
I also look forward to having the new parts fitted and seeing how it will handle then. The new TCAs are still in the box, it's way to cold to fit them now and the car is still off the road anyway until the weather is getting better.
I don't think it's a problem that the rear roll centre is lower with a 6 degree beam.
Ford had already thought of a beam with a smaller sweep angle when they made the RS500. It had special brackets mounted on the subframe to homologate the moved inner pivots for racing. The race version of the RS500 had sweep angle of 8 to 9 degrees, which was the maximum they could achieve within the rules.
I also look forward to having the new parts fitted and seeing how it will handle then. The new TCAs are still in the box, it's way to cold to fit them now and the car is still off the road anyway until the weather is getting better.
01-03-2018, 08:08 PM
#160
Regular Contributor
