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Sidecarbod
29-04-10, 02:23 PM
I wasn’t going to post this up but then I thought hey somebody might be interested so here goes! :p

I purchased a Sealey Camber/caster gauge the other day as I’ve never actually measured the caster on my car. The camber part of the gauge is useless because it reads from +6 to -6 so trying to set the camber at 0.2-0.6 is not really going to be possible with the gauge, not that it matters because my plumb weight method works very well for the camber. I think that Jeff mentioned that he had bought one of these gauges a while ago.

Anyway back to the caster, my wishbones are the “normal” ones that Pilgrim used to supply but the boss on the chassis has had about 12.5mm cut off the front so that the wishbone sits further back. (5 x 2.5mm thick washers pack out the space).

I measured the caster as per the instructions, it involves turning the wheel 20 degrees one way, setting the gauge to zero then turning the wheel the other way before reading off the measurement. I actually set the gauge to -1 rather than zero because it was virtually running out of range.

My driver side wheel ended up as 6 degrees positive caster, each washer was found to be worth 0.5 of a degree so that means that as standard there would only be 3.5 degrees of caster. This is not very much according to the wobbly web!

I then measured the passenger side which had the same mods and found that it was only 5 degrees! Luckily there was one washer at the front of the wishbone so I moved it to the back making 6 in total. (Either I cut slightly more of the boss or the wishbones or bushes are slightly different, this would account for the extra washer)

The caster on the passenger side then went from 5.0 to 5.5 degrees. What I will do it move one of the washers one the driver side to the front of the wishbone which should get the caster on that side to 5.5, in other words both sides the same. This will mean that one wishbone is packed back with 4 washers and the other with 6, this is a difference of 5mm but if that’s what’s needed then that’s what’s needed!

I also came across a very easy way to ensure that the top and bottom ball joints are not running out of travel, it is very dangerous if they do run out of travel, they could snap! Basically with the car jacked up and the wheel removed make sure that the suspension is on full droop as that seems to be the place where they are most likely to bind up, undo the bolt that holds the track rod ball joint onto the upright then knock the ball joint out of its tapered hole (Leave the nut flush with the bolt so that you don’t trash the threads). With the ball joint fully removed from the upright try swinging the upright left and right, it should not go tight at any point. If it does go tight try jacking the suspension up 10-20-30mm then try again. If it’s now OK then you have too much caster and you are overloading the ball joints. You could argue that the suspension will never be on full droop AND full lock, well that’s true, it’s your car and your live!

Needless to say that any messing about with the setup of your car will probably require the tracking and camber to be re-set. Oh another pain in the bum is that if you move the top wishbone a fair way then the rack height will need to be changed! Finally the size of your uprights and mushroom swill have an effect on how much the caster changes with each 2.5mm thick washer.

Rowly
29-04-10, 02:46 PM
Interesting Pete,
I have got a Sealy gauge, as you have said, not very accurate within the range you need for Camber, I actualy made one up, like your plumb bob, but made of metal. either way is good.
I also noticed a castor discrepancy, in packing top arm,from n/side to o/side.
I think there is a tendancy to "pinch" the bottom arm mounting plates, this could be either forward or backward, so I double checked the Wheelbase sizes & packed the bottom arm to suit first, then went through the procces of the top end setup again.
a bit tedious, but worth doing.

Sidecarbod
29-04-10, 03:16 PM
Interesting Pete,
I have got a Sealy gauge, as you have said, not very accurate within the range you need for Camber, I actualy made one up, like your plumb bob, but made of metal. either way is good.
I also noticed a castor discrepancy, in packing top arm,from n/side to o/side.
I think there is a tendancy to "pinch" the bottom arm mounting plates, this could be either forward or backward, so I double checked the Wheelbase sizes & packed the bottom arm to suit first, then went through the procces of the top end setup again.
a bit tedious, but worth doing.


All good stuff!

You need to get that car finished and on the road! :p

jeff
30-04-10, 09:39 AM
Yes Pete pretty useless for camber but OK for checking that castor is the same both sides which is why I brought one in the first place

Like yours I had a difference of about 1 degree from left to right, but the other way around

Mine is now set at 6 degrees both sides give or take a tad. Weird thing is I did not have to do the castor mod I had no problem with self centering for SVA and only found out I had 6 degrees when I brought the gauge.

I guess its just different mixes of wishbones, mushrooms and running gear fitted at the time.

I still think I have some slight bump steer issues that I am going to look at again as soon as time allows and I will also check my ball joint travel at the same time.

I have so much to do on the Cob this year and no bloody spare time, gearbox has to come out and replacement fitted if I am keeping a rover engine or the whole lot come out if I do go down the yank V8 route. At the moment I am strongley verring to a Chevy lump

Thanks for the info and writing it up

Sidecarbod
30-04-10, 10:27 AM
Yes Pete pretty useless for camber but OK for checking that castor is the same both sides which is why I brought one in the first place

Like yours I had a difference of about 1 degree from left to right, but the other way around

Mine is now set at 6 degrees both sides give or take a tad. Weird thing is I did not have to do the castor mod I had no problem with self centering for SVA and only found out I had 6 degrees when I brought the gauge.

I guess its just different mixes of wishbones, mushrooms and running gear fitted at the time.

I still think I have some slight bump steer issues that I am going to look at again as soon as time allows and I will also check my ball joint travel at the same time.

I have so much to do on the Cob this year and no bloody spare time, gearbox has to come out and replacement fitted if I am keeping a rover engine or the whole lot come out if I do go down the yank V8 route. At the moment I am strongley verring to a Chevy lump

Thanks for the info and writing it up


If I remember correctly your wishbones were different to some of the others that Pilgrim produced, the reason that I say this is that you had to put the ball joint locking nut on the otherside of the wishbone. (I think).

According to what I've read it does look like 5-6 degrees positive caster is a good figure to go for.

You do know that if you go to a "boat anchor" then in my humble it will need to knock out 400 BHP before it will out perform on the road, in the real world a 285-300 BHP Rover lump! (Not that building a 285-300 BHP is cheap)...Well that is the case up to 120 MPH, after that then the SBC may start to ease away. JMHO before people "kick off" :rolleyes:

Pete

jeff
30-04-10, 11:13 AM
Thanks Pete, had near enough made up my mind on going chevy now you have me thinking again LOL

I have costed it up and it works out about the same money if I sell my RV8 set up as a complete sytem carb, propshaft, stainless headers etc. just a shed more work going chevy.

Ian C
30-04-10, 11:20 AM
Hi,

I have been following the threads on setting up a Pilgrim Sumo with interest and a degree of veneration tinged with respect for those with considerable more skill and expertise in this field than I could command.

I acquired a Sumo kit in December 2009 and have been making steady all be it slow progress with many detours to install modifications out of personal choice and to embodied changes suggested by previous forum posts. The main of these is the considerable body of information concerning the suspension set up (– I can’t afford a big Chevy V8 or similar so my aim is to make the Sumo as nimble as possible).

Being an avid follower of the forum I have built a considerable volume of “advice” re the Sumo set up but I am applying this information, which largely stems from chassis (what is the plural of Chassis?) produced prior to the “re-birth” of Pilgrim, to a “new” chassis with “new” wishbones. The car is being built with Granada running gear from an “L” reg (93/94) Scorpio and fitted with a 3.9 EFi Rover V8, and LT77 box.

I determined to make as many checks and measurements during the assembly, when it would be easier to identify and change any parameters that would not suit my set up aspirations. To date I have checked the camber (acknowledgement to Sidecarbod for method) and the caster (acknowledgement to Rowly for gauge) and I have attached a synopsis of the results for those who may be interested (I would be happy to provide further information for any who may be at a similar stage).

My attention is now focused on eliminating any bump steer that may be present in my set up. To this end I fabricated a gauge using details from Allan Staniforth’s (who sadly died last year) excellent book “Competition Car Suspension” and have now performed initial measurements. The mounting posts on the “new” chassis have been lowered to 100 mm, presumable in response to the numerous suggestions that Den received when he regained control of Pilgrim, so I needed spacers rather than a hacksaw. Again I include the results for interest (only allowed 5 files so will send results in following post).

Can I take this opportunity to express my thanks to those who administer this forum and to those whose posts have been an absolute life line to those, like myself, who are embarking on a lifetime dream with more hope than expertise – Thank You

Ian C
30-04-10, 11:26 AM
Follow up with Bump Steer measurements as mentioned above.

Sidecarbod
30-04-10, 11:30 AM
Thanks Pete, had near enough made up my mind on going chevy now you have me thinking again LOL

I have costed it up and it works out about the same money if I sell my RV8 set up as a complete sytem carb, propshaft, stainless headers etc. just a shed more work going chevy.


I guess the down side of sticking with a Rover is you will have to build it yourself or pay someone quite a lot to do it for you where as there are loads of people that build yank lumps for not much money (Competition I guess). Also 400 BHP in "bread and butter" stuff to them where as a 300 BHP Rover lump can not just be bolted together using off the shelf parts.

Sidecarbod
30-04-10, 11:41 AM
Hi,

I have been following the threads on setting up a Pilgrim Sumo with interest and a degree of veneration tinged with respect for those with considerable more skill and expertise in this field than I could command.

I acquired a Sumo kit in December 2009 and have been making steady all be it slow progress with many detours to install modifications out of personal choice and to embodied changes suggested by previous forum posts. The main of these is the considerable body of information concerning the suspension set up (– I can’t afford a big Chevy V8 or similar so my aim is to make the Sumo as nimble as possible).

Being an avid follower of the forum I have built a considerable volume of “advice” re the Sumo set up but I am applying this information, which largely stems from chassis (what is the plural of Chassis?) produced prior to the “re-birth” of Pilgrim, to a “new” chassis with “new” wishbones. The car is being built with Granada running gear from an “L” reg (93/94) Scorpio and fitted with a 3.9 EFi Rover V8, and LT77 box.

I determined to make as many checks and measurements during the assembly, when it would be easier to identify and change any parameters that would not suit my set up aspirations. To date I have checked the camber (acknowledgement to Sidecarbod for method) and the caster (acknowledgement to Rowly for gauge) and I have attached a synopsis of the results for those who may be interested (I would be happy to provide further information for any who may be at a similar stage).

My attention is now focused on eliminating any bump steer that may be present in my set up. To this end I fabricated a gauge using details from Allan Staniforth’s (who sadly died last year) excellent book “Competition Car Suspension” and have now performed initial measurements. The mounting posts on the “new” chassis have been lowered to 100 mm, presumable in response to the numerous suggestions that Den received when he regained control of Pilgrim, so I needed spacers rather than a hacksaw. Again I include the results for interest (only allowed 5 files so will send results in following post).

Can I take this opportunity to express my thanks to those who administer this forum and to those whose posts have been an absolute life line to those, like myself, who are embarking on a lifetime dream with more hope than expertise – Thank You


Streuth!!! Were you a rocket scientist in a past life? :-P

Anyway, I think that the way the you have recorded you data is spot on and I have no doubt that you will be more than pleased when you get your car on the road!

Your bumpsteer curves look similar to mine if you turn mine on their side. Also you can clearly see that a few mm is enough to mess things up!

Pete

Ian C
30-04-10, 11:59 AM
Pete,

I was a computer engineer from when I left the RAF in 1970 until I retired last year (but as I have just recovered from a fatal hard drive error and had NO backups perhaps the less said the better)

Your comment re "a few mm can make a difference" brought a smile - when I made the bump steer gauge I scored reference lines, into the aluminium strips that I had used, to indicate suspension travel. I then painted over the score lines and rubbed the paint off leaving the lines nice and visible. When using the gauge the point of the dial gauge drops into the "line" causing a change of about "5 thou" in the reading which throws everything into confusion.

If I was building it again I would use a less sensitive gauge (the dial gauge was bought for rebuilding the Rover V8 and is Imperial causing further opportunities for confusion!).

Can you comment on my assumption that the ride height will be in the middle of the spring travel (i.e. half way between full droop and full bump) or is reality something different?

Thanks you again for all your input, it is much appreciated.

Sidecarbod
30-04-10, 12:23 PM
Pete,

Can you comment on my assumption that the ride height will be in the middle of the spring travel (i.e. half way between full droop and full bump) or is reality something different?

Thanks you again for all your input, it is much appreciated.


Good question!

On my car it is in the middle (give or take a fraction) but that is because I don't have my car setup like a "snakes belly" (i.e in the grass)

I was poking about with a couple of cars a while ago and they had both been setup much lower than mine, it transpired that they were both vertually sat on their bumpstops all the time....fools! ;)

I think that Den may have moved the top shock mount now so new cars can be set lower whilst still leaving some shock movement.

Regards,

Pete

Ian C
30-04-10, 12:48 PM
Good question!

I think that Den may have moved the top shock mount now so new cars can be set lower whilst still leaving some shock movement.

Regards,

Pete
Pete,

I can confirm that - the top mounting is moved up and in which causes the top wishbone to sit almost horizontal at full droop, rather than point down as previously, and increases the clearance for the spring & shock. The difference is quite pronounced and I thought that I had made a basic error somewhere until I received confirmation from Den of the changes. I attach a drawing I made showing the difference between mine and "Chedz" using a photo of front suspension from the wiki site (which again is an invaluable source) - apologies for the quality, I had to scan my copy having lost the original in the hard drive failure.

Best regards,

Sidecarbod
30-04-10, 12:59 PM
Pete,

I can confirm that - the top mounting is moved up and in which causes the top wishbone to sit almost horizontal at full droop, rather than point down as previously, and increases the clearance for the spring & shock. The difference is quite pronounced and I thought that I had made a basic error somewhere until I received confirmation from Den of the changes. I attach a drawing I made showing the difference between mine and "Chedz" using a photo of front suspension from the wiki site (which again is an invaluable source) - apologies for the quality, I had to scan my copy having lost the original in the hard drive failure.

Best regards,


Are you absolutely sure that you had nothing to with rockets in a past life? :-P;)

Ian C
30-04-10, 01:12 PM
Spadeadamm isn't far away but that is the closest I have come (though I did "receive" a few when in the RAF)

Seriously though my mantra has always been to do things as well as you possible can and stand by them. Building the Sumo is without doubt the most satisfying and rewarding thing (leaving out all the sloppy stuff like courtship, marriage, chlidren, grandchildren etc etc) that I have ever done - can't think why I did not retire straight from school and start building kit cars then?

Best regards,

jeff
30-04-10, 04:10 PM
I am never going to post any more pics of my jottings on cornflake boxes from now on lol

Ian C
30-04-10, 04:28 PM
I am never going to post any more pics of my jottings on cornflake boxes from now on lol
Jeff,

Some would point out that I am retired now and have nothing else to spend my time on, others would mention that perfectionism is the worst form of self abuse and still others (my wife included) would point out that things should be "fit for purpose" rather than act as a vain glorious exercise in self promotion, it is after all the content rather than the presentation that is important.

I actual enjoy, and get a lot of pleasure out of, using apps like Excel to produce graphs and Visio to do technical drawing. I suppose I am hoping that if the information looks "professional" the experts on the forum will not question my credentials too closely (at least until I prove that I can build a car which can be driven).

Regards,

tonym
30-04-10, 05:16 PM
a 300 BHP Rover lump can not just be bolted together using off the shelf parts.

You may be surprised there Pete ;)

Sidecarbod
30-04-10, 05:33 PM
You may be surprised there Pete ;)

How come Sir? :p

Your's is not off the shelf the same as mine, you heads have had to have a shed load of work done to them. With SBC stuff you can choose from loads of heads out of a catalogue.

Aha, I bet you say "Merlin" heads, OK that one on the list!

tonym
01-05-10, 04:44 AM
How come Sir? :p

Your's is not off the shelf the same as mine,

You go visit John Eales and look at his shelves!!!!! :cool:

Sidecarbod
01-05-10, 08:10 AM
You go visit John Eales and look at his shelves!!!!! :cool:


OK point taken! :p

But what I meant was that there are no manufacturers making heads apart from the merlin jobbies, JE will have spent many hours modifying standard heads then stacking them up on his shelves.