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  1. #1
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    Pilgrim Sumo MK3 Modifications Part 1

    This was translated from Dutch and posted in the Pilgrim Sumo owners on Facebook, I couldn't upload the word doc as it's too big.

    So on multiple posts.

    You can download it from the Facebook page.

    I've not seen the stiffener bars added to the rear swing arms before?




    Pilgrim Sumo MKIII (Sierra kit) mods.


    Be aware: All descriptions here are for the Pilgrim Sumo Sierra kit !!

    Pilgrim had in the nineties also Cobra kits based on a Ford Cortina, Granada (mkI en II), a Rover V8 or a Jaguar !

    1.Steering.


    The steering rack is from a Ford Sierra, the front wheel hubs are from a Ford Scorpio (Granada mkIII).
    If your steering turns back when one or both of your front wheels go into a deep hole, this is called steerbump.
    Change the following:
    Your steering rack with steering rods are mounted on 2 small pipes at an angle. The steering assembly is bolted down by 2 bolts.
    Use a grinder to reduce the height of these small pipes with 8 till 12 mm (metric).
    (According to Pilgrim [late nineties] they are 10 mm too high).
    By this you lower the overall steer rods and steering rack assembly.
    How many millemeter (mm) ??
    Go to a company who can align your wheels and steering geometry.
    When you put load on your steering assembly (by pushing the front of the chassis downward)
    The wheels should start reading toe-in. If not cut a few mmm of the small pipes again.
    If toe-in occurs to quickly put 1 or 2 shims to set the steering assembly a little bit higher.

    The standard Sierra steering rack has a 4,5 steer revolutions from left to right. I find this too much. I changed the internals (bought at Burton Power) so it is now 2,25 steer revolutions from left to right. It steers more like a sportcar but you need more muscle !


    1. Rear wheel alignment.

    At the rear of the chassis you will have wishbones from a Ford Scorpio (Granada MKIII) or Sierra V6.
    To start with the wheel alignment is wrong.
    The rear wheels have standard 4 – 6 degrees toe-out !! They should stand straight ( zero degrees). You will notice this when you drive through grooves en channels (made by heavy traffic) in the tarmac, the rear will feel as if it wants to go the other way as you intended (it can feel wobbly).
    Solution ??
    Make the insight holes for the big bolts which keeps the rear wishbone attached to the chassis, larger by expanding them to the rear about 6 – 8 mm ( do not make the hole itself bigger just lengthen the opening. When you have done this you can make the rear wishbone go a little more to the outside and by this align your rear wheels at zero degrees. (do this for both sides)
    Make sure you go to your local garage and have it checked on the wheels alignment machine and make adjustment if necessary.
    3.Backend, beter roadholding.


    The rear wishbones have flexibility due to the standard rubber bushes the are in.
    Especially when you drive on trackdays or are an enthousiastic driver like me you will notice the backend is not as stable as you would like when cornering fast.
    To make the backend stable you will need a mechanism to ‘hold’ the rear wishbones so they can not move a bit.
    You will need a construction to hold your wishbones tight but also make sure the wishbones can move up and down.
    Please remember your rear wishbones make a large circle when moving up and down.
    A construction (please look careful at the 2 pictures) has been made from the end of the wishbone (with a rubber bush) connecting a rod to the holding plate at the back of the chassis.
    You can see the rod in adjustable to make a correct alignment possible.
    Roadholding has improved dramatically.

    Again check correct alignment at your local garage.









    4.[IMG]file:///C:/Users/user/AppData/Local/Temp/msohtmlclip1/01/clip_image002.jpg[/IMG]Differential mounting bracket !


    The diff is from a Scorpio (Granada mkIII) or Sierra.
    The standard diff mounting bracket is too weak, to say the least !!
    After an enthusiastic ride up the mountains in Austria, my diff mounting broke in 2 and the extra diff bracket bolts snapped like matches (see photo).
    Because I knew that the standard diff mounting brackets was too weak I already had a special made diff mounting bracket made for the lower end of the diff (see photo).














    I have had the standard diff mounting bracket enforced by 2 mm thick steel plates (see photo). This will not break down again !Two Cobra technicians have studied in depth the Pilgrim Sumo MKIII chassis (in the late nineties) but also others (DAX, etc).
    A document was written by Gert Verbeek (with the help of Jelle Zijlstra) and published in the Dutch Cobra Club magazine.
    These gentlemen describe the modifications they did to the Sumo mkIII chassis to create a much better and safer road holding.

    I, Dick Vesters, have made the same modification (most of them carried out by third parties).
    The only modification I tried but did not apply is the 700 lbs springs at the rear.
    This makes the Cobra a hard bouncer ! So I used 550 lbs.
    Overall result is very good steering and road holding sportcar.
    -----------------------------------------------------------------------------------------------------------------

    Gert Verbeek wrote:
    “Last winter I decided that after some publications from Jelle in the Dutch Cobra magazine, to study the test the Sumo mkIII chassis. Of course I have asked Jelle to help me.
    The reason ?
    I wanted to make modifications to my chassis (Sumo mkII 1999) to get a better and safer road holding.
    The handling was downright dangerous in my eyes;
    The car suffered a lot from bump steer and the behavior on bumps and potholes
    road was downright unpredictable, the steering behavior was choppy, a little bit everything
    or nothing.
    We have started with the dismantling of the entire front suspension assembly, whereby immediately a big mistake emerged; the upper wishbones were reversed
    mounted. I remember using the photos during construction I could not clearly see where the long and the short sides of the wishbones had to be positioned exactly, so I asked World of Cars (Pilgrim Sumo importer NL) for advice and that advice was wrong.
    This advice may have been related to my choice of tires and wheels; American Racing rims and Continental tires in the sizes; front 205-60 R15 and rear; 255-60 R15.
    The ET value of these rims differs slightly from the most commonly used Hallibrand replica rims from Image.
    On closer examination of the suspension points and after extensive measurements on the
    chassis we also came to the conclusion that the suspension points for the lower
    control arms on both sides of the car are in the wrong position on the chassis were welded. We first made a cross measurement from the bar behind the transmission tunnel to the bulkhead and to the parallel running chassis beams that run forward from the bulkhead.
    This showed that this chassis was in any case straight and not shorter on one side than on the other.
    In addition, this also showed that the bulkhead was straight with respect to the rear part of the chassis (very important !).
    This made it possible to accurately measure the chassis beams from the bulkhead, which subsequently turned out to be the same length.
    This is more than we can say of some other chassis that we measured recently, in these we sometimes found differences in length of the front beams and / or a somewhat skewed bulkhead.


    The lower attachment points for the A wishbone arm were not only welded at the chassis at the wrong position but were also positioned wrong (1,5 cm difference) relative to each other on both sides.
    After measuring exactly where we wanted to place the new lower attachment points, the old ones were grinded off and we have we made new suspension points and welded them onto the chassis.
    Remember you measure from the bulkhead.







    For modification on the steering rack please see point 1.

    The suspension points for the upper wishbones also turned out to be wrong, we
    have these pipes at the back shortened by approximately one centimeter (see photo) and
    the wishbones are reassembled with a custom turned sleeve between them on the
    front.
    Due to these measures, it was possible to change the caster (which is normally one
    fixed value and is therefore not adjustable with the Pilgrim) to be corrected to one
    desired position.
    The caster is the angle the wheel upright makes relative to a 90 degrees perpendicular to the car.
    By moving the lower wishbone arm or the higher wishbone arm you can make the changes to the degree of caster.








    A = top ball joint
    B = lower ball joint

  2. #2
    Join Date
    Mar 2009
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    Adjusting and increasing the caster has a number of effects; because the wheel has as it were been put down, the car will drive better in a straight line and the car will return the steering wheel by itself to a straight drive position after taking a turn.
    A (small) disadvantage can be that the car will steer a bit heavier.

    It has been written before by both Jelle and me; you can fine tune your chassis in two
    basic ways; for racing or for cruising and a lot in between.
    In this case we have made a few compromises, the starting point was perfect handling of the steering behavior and very good road holding of the car.
    As you will discover later in this article there are a number of different procedures
    necessary, which must also be optimally coordinated and adjusted to one another.

    The next job was to reassemble all front wheel suspension parts and adjust the camber. The camber is adjustable on the Pilgrim and is realized by turning the stud in or out of the upper wishbone.
    To be able to check this fairly accurately, we used an electronic spirit level that can also display degrees.
    A requirement here is that the car is level!
    During assembly the rear springs (550 lbs) have been moved to the front and at the rear we have fitted 700 lbs springs.
    The car has a negative received camber.


    I, (Dick Vesters) have the following specs :
    Front springs 450 lbs
    Front suspension : Gaz
    è 8 clicks
    Spring : hand tight plus 1 revolution
    Rear springs 550lbs
    Rear suspension : Spax è 6 clicks
    Spring : hand tight plus 5 revolutions

    The wheel positions in figure two are deliberately drawn exaggerated to make the principle clear

    See figure 2.





    Camber 0 = camber 0
    Camber positief = camber positive
    Camber negatief = camber negative


    The Spax dampers have also been reset by first returning them to the zero position and then they have received 4 clicks. (for the Spax type what is used for the Sumo chassis each click corresponds to about a quarter turn).


    We also looked at the Ackermann principle.
    The Ackermann principle is a variable angle with three constants: zero when driving straight ahead and respectively a certain angle that arises between the front wheels if you steer all the way to the left or right, the inner wheel then makes a sharper bend than the outer wheel.
    When you draw a line backward from the steering ball joint at the front wheel through to the center of the rear axle (or diff), the lower upright ball joint should fall on this line with the wheels in the straight ahead position.

    See figure 3.







    Stuurkogel = steering rod ball joint
    Fusseekogel = lower upright ball joint

    Midden van de achteras = middle of rear axle or diff.





    Finally, we have set the toe-in at the front suspension, do this by turning the track rods in or out according to which direction you want to set it.
    At the same time we have also placed the steering box in the middle so that the steering angle to the left and right is the same and the steering wheel can then be mounted in the middle position.

    See figure 4.





    Uitspoor = toe-out
    Toespoor = toe-in





    The amount of tracking on the rear wheels (slight toe-in where the values l and r equal!) is decisive for the driving line (= tracking rear wheels with respect to the center line of the
    car) and the overall handling of the car along with the other changes results in a car with completely different driving characteristics.

    Not only the front but also the rear a number of things have been adjusted; the springs at the rear are now of a heavier type 700 pounds, the dampers are set at 6 clicks
    and the rear suspension has been adjusted by milling the holes in the chassis for the inner leg of the wishbones backwards by 8 mm. (see als point 2)
    As a result, the rear suspension can now be adjusted for toe-in.

    Figure 5.







    De punten A zijn de locaties van de gaten die uitgefreesd moeten worden =
    Points A are the locations of the holes to be milled.



    With reference to figure 5 it becomes clear that if you make to the holes at points A
    milled up to 8 mm at the back that it will then be possible to adjust toe-in


    After all these interventions, it goes without saying that you check everything again as much as possible, before going to your local garage for the alignment bridge.
    If all is well then the alignment technician only needs to make some fine adjustments.
    At least that was the case with us.
    Make sure you look up a company with very skilled staff who really understand the wheel alignment of cars otherwise you might get very frustrated and bad results.
    The alignment data can be used from a Scorpio or from a Mazda 626.

    We used the following specs:


    Camber = - (min)1,5 degree negative
    Caster = 3 degrees positive
    Toe-in front = 0-1 mm toe
    Toe-in rear = 0-1 mm toe


    Remark: the driving line must be 0 !


    If you are still building or have yet to start, it is best to make these changes (if you want to implement them) as early as possible.
    I now know that carrying out these activities under a completed car is a “hell of a job”.
    In connection with our findings, we measured a chassis this spring that was supplied by the Belgian importer for Pilgrim (2002) and here we also found usual shortcomings.
    However, it is clear to us that one chassis is certainly not the other, the las-jig may have suffered from years of use and therefore the dimensional tolerance is no longer optimal.

    In the meantime there is a new owner (tony holmes) of the Pilgrim factory and some work on the mkIII chassis has been done in the meantime.
    If you start measuring yourself, make sure that you measure everything over and over.
    Use as many tools as possible, e.g. electronic level to measure angles in the vertical plane and use a large square hook to attach directly to the chassis to measure.
    Keep in mind that the body of a Pilgrim is certainly not entirely symmetrical, precisely for this reason in particular the suspension points on the right side are already slightly different than they should be.
    So don't think I'll straighten it up because then your chances are you'll be in
    trouble when your body goes on.
    What you have to be aware of is there a wheel can run against the mudguard when you turn in.
    So if you are changing the suspension points at the front, so DO try fit the body and position it properly and fix it to prevent shifting.

    Finally, a warning: if you do not properly understand the effects of these interventions
    you better leave it to someone who does have this knowledge because
    in the end you change very essential things about your car.
    So the consequence can be that it will not work as you expected.
    Moreover, this description only applies to an MK 3 chassis and not to the MK 1 and 2 which have a completely different front suspension.

    As for my car; the whole handling of the car has totally changed and it is like going from hell to heaven, a super nice steering car with very great control and better handling than ever.
    During our drive to the Nürnburgring (Germany) we have tested this extensively and found it to be good


    Regards, Gert van Beek.

  3. #3
    Join Date
    Aug 2009
    Location
    Birmingham
    Posts
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    Thanks for posting the information.
    It just does....

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