jeffw
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| posted on 14/5/13 at 01:36 PM |
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My trip to Procomp
As some of you will know I went up to Birmingham last weekend to visit Procomp to get the car set up.
Arrived just after 10am on Saturday and after the normal greetings got the car into the workshop (which is behind their residential house). Mug of
coffee later and we are ready. Car is quick lifted and the bonnet comes off closely followed by the front shocks. The settings and which side they
came from are noted and then they are cleaned up and the spring removed. The shocks then go on the shock dyno to be measured at each click setting.
Interesting aside here that the shock dyno (made by Intercomp) is designed to work with heavy, US, shocks on big cars and it had issues with noise or
interference on the graphs so Procomp removed the motor and isolated that for vibration and the set the dyno on vibration mounts.
So the graphs for my front 'matched' pair of shocks showed there was a 300lb difference in rebound valving and that the shocks had never
been put into their operation range in the factory. So not a pair and never been set up  The rears are taken off and the same process is gone
through, slightly better news is they are pretty much a pair and are in the correct working range. Next all the springs are tested (regardless of what
is written on them) and they are 225lb front and 200lb rear and match across the axle. They then adjust the shocks so they match as close as possible
across the axle although the fronts need replacing really they don't carry stock as each car needs different valving. The operating range for
the rear shocks (out of 13 position on the knob) is 9-10 clicks and the fronts are 3-6 clicks....think about that then you are clicking your
adjusters.
Shock/Springs are put back on the car and the setup can commence. They first check all the bearings and trackrod ends (one of the front bearings is
loose so that is fixed and both bottom tapers are also loose !) then camber is set based on the look of the tyres...2.4 deg neg left and 2.6 deg neg
right, this is checked with the Mk1 human (Ivan the dad) standing on the chassis to ensure it isn't changing under compression
And so it continues through caster, thrust angles, toe (front and back)....all of them with me in the car. They adjusted the steering rack to make it
central, the rear axle so it was giving the best thrust angle and so on. They then corner weighted the car (623Kg) and adjusted it to give 7Kg more on
the passenger side front so that both tyres would lock together rather than the one tyre.
All of this is done with lots of questions being asked of me as to how the car handles currently and lots of banter. There was lots of things going on
with the car I don't even remember but it wasn't till 8pm that I left Birmingham....So I need two new front shocks (£100 each which will
be valved and dynoed for the car) and £226 for the setup (two skilled engineers for 10hrs !) Didn't think that was half bad.
Final settings are
Camber left 2.4 deg neg, right 2.6 deg neg
Castor left 4.687, right 4.593
Tracking 2mm toe out (at rims)
Rear
Camber left 0.3 deg neg, right 0.2 deg neg
Tracking 1.2 mm toe out at rims
Thrust alignment at chassis front 6mm to the left
Corner weights
Left 346.5Kg 47.4%
Right 384.5Kg 52.6%
Rear 376.5Kg 51.5%
Cross 346.0Kg 47.3%
Front Left 179, right 175
Rear Left 169, right 207.5
Total with driver 731.5Kg
Damper Settings
Front 3,4,5,6 (Set 4)
Rear 9,10 (Set 9)
Front Springs 225lb
Rear Springs 200lb
Rake is set to 25mm
I went sprinting on the Sunday at Debden and it is a very different car to drive.....took me 4 runs to work it out. The datalogging shows I can use
0.2 G extra force on the brakes before locking (which is a massive improvement) and 0.1G in the corners. The car feels planted now which much more
front end and this is before the correct shocks. I'm off up to Llandow for a trackday Saturday and will be able to try it with the ARB
disconnected (Procomp want me to test with and without my very stiff ARB).
So highly recommended.....just remember that those shocks on your car which have never been measured will not be even close to each other unless you
get them dynoed. Thanks to Ivan and Matt for the banter, coffee and all the hard work.
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maccmike
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| posted on 14/5/13 at 01:50 PM |
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seems an absolute bargain
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bi22le
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| posted on 14/5/13 at 02:05 PM |
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Sounds like you had a very similar day to mine, including the story of the shock dyno!
I can't agree more though. The service and knowledge they have offered for the price was incredible. I was a little locker than you with the
damper checks but I still need new ones as well!!
The service that procomp offer is just mind blowing value for money. I also had 10 hours spanner work from 2 experienced people for the flat fee.
Great work Ivan and Matt, keep it up.
Track days ARE the best thing since sliced bread, until I get a supercharger that is!
Please read my ring story:
http://www.locostbuilders.co.uk/forum/13/viewthread.php?tid=139152&page=1
Me doing a sub 56sec lap around Brands Indy. I need a geo set up! http://www.youtube.com/watch?v=EHksfvIGB3I
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emwmarine
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| posted on 14/5/13 at 02:24 PM |
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Is there anyone is Essex who can do this?
Building a Dax Rush.
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welderman
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| posted on 14/5/13 at 02:26 PM |
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Nice write up there, thats where my car will be going when its finnished  .
WHEN ITS FINNISHED !
Thank's, Joe 
I don't stalk people
http://www.locostbuilders.co.uk/forum/23/viewthread.php?tid=172301
Back on with the Fisher Fury R1
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nick205
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| posted on 14/5/13 at 02:28 PM |
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Sounds like people working at what they enjoy and enjoying their work...quite a rare thing!
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nick205
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| posted on 14/5/13 at 02:29 PM |
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quote:
Originally posted by welderman
Nice write up there, thats where my car will be going when its finnished .
WHEN ITS FINNISHED !
Sure it's not Swedish
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twybrow
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| posted on 14/5/13 at 02:46 PM |
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quote:
Originally posted by bi22le
Sounds like you had a very similar day to mine, including the story of the shock dyno!
I can't agree more though. The service and knowledge they have offered for the price was incredible. I was a little locker than you with the
damper checks but I still need new ones as well!!
The service that procomp offer is just mind blowing value for money. I also had 10 hours spanner work from 2 experienced people for the flat fee.
Great work Ivan and Matt, keep it up.
I stand by the statement that this was the best money I ever spent on my car. Great guys, and a great service. I reckoned that the changes they made
were good for about 30% higher cornering speed than before I went. I have not changed my shocks/dampers from the day they set them, but one day I
might get round to trying the full range of clicks that actually work!
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rodgling
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| posted on 14/5/13 at 02:48 PM |
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quote:
Originally posted by emwmarine
Is there anyone is Essex who can do this?
I've just taken my car to AB Performance in Suffolk. They did a great job on my car, basically the same sorts of things as JeffW had done. I
took it to Brands the next day and couldn't believe how much better it was. It was obviously miles better than the very wrong setup I'd
done on it previously, but also much better than a very similar spec GKD that had been setup by someone else (much less understeer on turn-in and
higher cornering speeds).
So would highly recommend these guys.
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jeffw
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| posted on 14/5/13 at 02:51 PM |
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Do AB have a shock Dyno?
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jeffw
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| posted on 14/5/13 at 02:52 PM |
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quote:
Originally posted by emwmarine
Is there anyone is Essex who can do this?
Maybe....but they'll not be Procomp. I went from Kent to Birmingham for this....Essex is closer.
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rodgling
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| posted on 14/5/13 at 03:08 PM |
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quote:
Originally posted by jeffw
Do AB have a shock Dyno?
They mentioned they were just in the process of setting one up. One of their guys used to do shock design in F1 so they ought to know their onions
when it comes to shocks.
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bi22le
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| posted on 14/5/13 at 03:47 PM |
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quote:
Originally posted by jeffw
quote:
Originally posted by emwmarine
Is there anyone is Essex who can do this?
Maybe....but they'll not be Procomp. I went from Kent to Birmingham for this....Essex is closer.
They mentioned to me that they were one of the few and that various companies send their shocks to them for testing.
I also drove from Kent to procomp for this set up. I also noticed a big difference in handling speed.
Track days ARE the best thing since sliced bread, until I get a supercharger that is!
Please read my ring story:
http://www.locostbuilders.co.uk/forum/13/viewthread.php?tid=139152&page=1
Me doing a sub 56sec lap around Brands Indy. I need a geo set up! http://www.youtube.com/watch?v=EHksfvIGB3I
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matt_gsxr
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| posted on 14/5/13 at 05:06 PM |
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Jeff, 108kg?
To miss-quote Colin Chapman
"To add speed remove pies"
Matt
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jeffw
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| posted on 14/5/13 at 06:12 PM |
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Sadly at my age all you have left is the pies. Still....car just about moves with me in it !
Are you are Llandow Saturday Matt?
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matt_gsxr
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| posted on 16/5/13 at 10:03 AM |
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quote:
Originally posted by jeffw
Are you are Llandow Saturday Matt?
Not me. Too scared. Actually hadn't realised it was an option.
Just getting the car back up and running after a 1 year lay-off, so lots of silly little things to sort out (as well as the normal big things).
Matt
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phelpsa
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| posted on 16/5/13 at 11:02 PM |
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There are plenty of companies around that will do what they do, damper dynos are not particularly rare, however most places would charge in the order
of 5 times more for an equivalent service.
And their toasties wouldn't be half as good!
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johnH20
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| posted on 17/5/13 at 09:47 AM |
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Amazed that you are running toe out at the rear, only ever heard of this on understeering FWD cars, but then what do I know. If it works it must be
right!
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40inches
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| posted on 17/5/13 at 11:07 AM |
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quote:
Originally posted by johnH20
Amazed that you are running toe out at the rear, only ever heard of this on understeering FWD cars, but then what do I know. If it works it must be
right!
That's what I was thinking. I always thought that rear toe out was a short cut to the nearest ditch 
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Sam_68
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| posted on 17/5/13 at 12:20 PM |
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quote:
Originally posted by 40inches
quote:
Originally posted by johnH20
Amazed that you are running toe out at the rear, only ever heard of this on understeering FWD cars, but then what do I know. If it works it must be
right!
That's what I was thinking. I always thought that rear toe out was a short cut to the nearest ditch
'Tis a live axle, so you get what Ford's manufacturing tolerances give you on both toe and camber...
...Unless you go to the trouble of correcting it, of course. The traditional method is by carefully localised heating and cooling of the axle tube
with a blow torch: the tube expands where heated but doesn't contract quite as much when it cools.
Toe isn't so critical on a live axle, though, as you don't have all the deflections in bushes and joints that you get with an IRS... a
typical IRS frequently gives significant changes in toe under acceleration and (particularly) braking due to these deflections: it's mainly the
change in the direction the wheels are pointing under varying loads that makes things feel horribly unpredictable, rather than any fixed amount
of scrub due to the toe setting.
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40inches
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| posted on 17/5/13 at 12:54 PM |
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quote:
Originally posted by Sam_68
quote:
Originally posted by 40inches
quote:
Originally posted by johnH20
Amazed that you are running toe out at the rear, only ever heard of this on understeering FWD cars, but then what do I know. If it works it must be
right!
That's what I was thinking. I always thought that rear toe out was a short cut to the nearest ditch
'Tis a live axle, so you get what Ford's manufacturing tolerances give you on both toe and camber...
...Unless you go to the trouble of correcting it, of course. The traditional method is by carefully localised heating and cooling of the axle tube
with a blow torch: the tube expands where heated but doesn't contract quite as much when it cools.
Toe isn't so critical on a live axle, though, as you don't have all the deflections in bushes and joints that you get with an IRS... a
typical IRS frequently gives significant changes in toe under acceleration and (particularly) braking due to these deflections: it's mainly the
change in the direction the wheels are pointing under varying loads that makes things feel horribly unpredictable, rather than any fixed amount
of scrub due to the toe setting.
Got it. Thanks for that 
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johnH20
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| posted on 17/5/13 at 05:27 PM |
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Thanks for the explanation, I suppose I should have guessed it was alive axle from your rear camber settings ( axle bent in another plane! ). I
suppose what happens dynamically with a live axle depends on your longditudinal location. If the axle skews in roll the steer angle of the loaded
outer wheel is going to be something else again. All very interesting.
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jeffw
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| posted on 19/5/13 at 12:32 PM |
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quote:
Originally posted by johnH20
Amazed that you are running toe out at the rear, only ever heard of this on understeering FWD cars, but then what do I know. If it works it must be
right!
As has been stated it is inherent to the Live axle I have which has has various bits welded to it over the years. Isn't a big issue and I
managed a 44sec lap at Llandow yesterday at the CKC trackday so it must be doing something right.
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Texan
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| posted on 21/5/13 at 09:02 PM |
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quote:
Originally posted by jeffw
So the graphs for my front 'matched' pair of shocks showed there was a 300lb difference in rebound valving and that the shocks had never
been put into their operation range in the factory. So not a pair and never been set up
What does this mean?
Are you saying that the shocks were defective from the factory or that there is something that has to be done after assembly to
"initialize" the shocks so they work properly.
I drive therefore I am.
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jeffw
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| posted on 22/5/13 at 05:20 AM |
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Effectively they where never checked in the factory. There is nothing you can now do to them to match them as the valving is different hence the need
for two new shocks.
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