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1994 Penske PC23 Indy Car


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#51 Nigel Beresford

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Posted 31 October 2012 - 00:21

What is the fit of these pins in the rod-ends, hand push?


Yes, a reamed sliding fit. It's the sort of thing the mechanics asked for. As I say, in retrospect it would have been better to do what we did in later years, and put anchor nuts on there.


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#52 gruntguru

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Posted 31 October 2012 - 01:17

Its not clear in the photo but the pushrod connection to the rocker seems to be bolted. No doubt due to the higher force/smaller displacement making the connection much more sensitive to clearance.

Edited by gruntguru, 31 October 2012 - 01:17.


#53 Tony Matthews

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Posted 31 October 2012 - 06:07

Isn't it also the case that the ARB rod has three alternative positions on the rocker, and the pushrod only one? Therefore, there must be the ocasional need to quickly change the leverage to the ARB and pins are quicker to remove and replace. There must be times when a rapid damper swop is necessary too. Just a thought...

#54 Nigel Beresford

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Posted 31 October 2012 - 09:21

Isn't it also the case that the ARB rod has three alternative positions on the rocker, and the pushrod only one? Therefore, there must be the ocasional need to quickly change the leverage to the ARB and pins are quicker to remove and replace. There must be times when a rapid damper swop is necessary too. Just a thought...


You are right, sort of. Though we had options for the ARB pickup, I can't remember ever changing during a session - the stiffness range available via the blades and torsion bar combo in whichever one of those options we were running was always sufficient to satisfy whatever setup needs we had. If we had had to change mid session then it would have been because we were in big trouble. If we were at the extreme end of adjustment (i.e. full stiff or full soft) then we would have moved the link and hence the range between sessions to give ourselves and the driver some adjustability.

As for the damper pickup, the quick-detach pin at the front was there primarily to facilitate spring changes (pull the pin and, with the car on the jacks, there was sufficient droop to allow the rocker to swing forward out of the way to free up the forward eyelet and swing the coil/damper assembly upwards to pull the spring off forwards). To change the whole damper (which we did occasionally) required undoing a bolted joint at the aft end, which was pretty fast to do anyway.

We wouldn't have considered a quick change pin at the top of the pushrod. You want a nice, tight, secure clamped joint for that, and if you were going to do it with anything other than a bolt then the press fit required would have made it slower to do rather than faster. Besides, I can't think of a reason to have to disconnect the pushrod in mid session, unless something unforeseen has occurred.

Edited by Nigel Beresford, 31 October 2012 - 09:27.


#55 Patrick Morgan

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Posted 31 October 2012 - 12:55

Some pictures of the engine oil heat exchanger - this lives in the left hand side-pod.

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Restored Engine Oil Heat Exchanger by dtperformanceltd, on Flickr

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Engine Oil Heat Exchanger by dtperformanceltd, on Flickr

#56 Patrick Morgan

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Posted 31 October 2012 - 12:56

And the gearbox heat exchanger which is mounted to the right hand flank of the tub. It also houses the alternator heat sink which is the big black lump in the top.

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Restored Gearbox Heat Exchanger by dtperformanceltd, on Flickr

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Gearbox Heat Exchanger by dtperformanceltd, on Flickr

#57 Woody3says

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Posted 31 October 2012 - 13:42

This is sheer pornography and you are all under arrest.

:p Hush you, we like our smut finely polished around here! :rotfl:




When you have to remanufacture parts for old cars like this, do you contact Penske to try and get source material (ie blueprints) for rebuilding? The pins are not hard to make, thinking about the more complex pieces.

#58 Patrick Morgan

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Posted 31 October 2012 - 13:59

:p Hush you, we like our smut finely polished around here! :rotfl:




When you have to remanufacture parts for old cars like this, do you contact Penske to try and get source material (ie blueprints) for rebuilding? The pins are not hard to make, thinking about the more complex pieces.


With any project like this it's ideal if you can get hold of drawings but it's very, very rare. You say the pins are't hard to make - they might look simple but there is a good amount of detail in them and they don't lend themselves to easy machining. You also have to be really carful when you have them heat treated that the flange doesn't bend and the surface doesn't get too scaly. In this case I redrew them from the originals.

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C0183-01-PC23 Rocker Pin by dtperformanceltd, on Flickr

Edited by Patrick Morgan, 31 October 2012 - 14:10.


#59 Patrick Morgan

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Posted 31 October 2012 - 14:09

The front airjacks ready to go back together. These are mounted in the sculpted pontoons ether side of the drivers hips.

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PC-23 Front Airjacks by dtperformanceltd, on Flickr

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#60 Woody3says

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Posted 31 October 2012 - 16:10

You say the pins are't hard to make

Sorry, didn't mean for it to come across that way. I'm in aircraft manufacturing so I understand you there ;) Any reason why you dont harden them and THEN grind the flange to size? Cost being the probable obvious answer.

#61 Tony Matthews

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Posted 31 October 2012 - 16:21

The front airjacks ready to go back together. These are mounted in the sculpted pontoons ether side of the drivers hips.

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PC-23 Front Airjacks by dtperformanceltd, on Flickr

The 'hip' position of the air jacks...
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...and installed and covered, unfortunately. I don't seem to have a photo of the jack in place but uncovered.
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Edited by Tony Matthews, 31 October 2012 - 16:25.


#62 Patrick Morgan

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Posted 31 October 2012 - 17:04

Sorry, didn't mean for it to come across that way. I'm in aircraft manufacturing so I understand you there ;) Any reason why you dont harden them and THEN grind the flange to size? Cost being the probable obvious answer.


Although this is not an unlimited cost exercise it's not down to that. The original pins we have appeared to be turned and then hardened rather than ground - you can faintly see turning marks on the shank under a magnifying glass. I wanted to replicate the original manufacturing process. If I were designing this part from scratch in my previous life it would have been ground post heat treat. It's entirely possible that the original first off pins were ground as the part has centre holes (which the machine shop we use bemoaned as being un-nessesery detail but I made them put them in anyway). It's certainly true that it's cheeper to make them without grinding if you can get away with it which it seems you can - having a consciences heat treater probably helps.

I do try really hard to get the detail right which drives suppliers nuts sometimes and does cost a bit more (there is a balance you have to strike). Basically you don't want anyone to be able to tell the difference between an original and the new part although I'd not go as far as trying to claim a new part as an original - I've always felt there is something un-ethical about that. If we can save the original bits we do everything we can to.

Edited by Patrick Morgan, 31 October 2012 - 17:07.


#63 Patrick Morgan

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Posted 31 October 2012 - 17:45

...and installed and covered, unfortunately. I don't seem to have a photo of the jack in place but uncovered.
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As you can see it in Tony's photos I thought a picture of the air jack valve block wouldn't go amiss...

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Air Jack Valve by dtperformanceltd, on Flickr

#64 Patrick Morgan

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Posted 31 October 2012 - 17:47

Some assorted gearbox parts - shout if you're getting board of these pictures. The little splined caps cover the gearbox input and output shaft nuts which are themselves splined. They are very satisfying to work with as you can't round them off.

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Assorted Gearbox Parts by dtperformanceltd, on Flickr

Edited by Patrick Morgan, 31 October 2012 - 17:47.


#65 Woody3says

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Posted 31 October 2012 - 18:04

We want more pics so keep em coming!

I like you wanting to keep as close to original manufacturing as possible. With the number of pins made at the time ill bet there was a die made to quench multiple pieces at once. That would reduce the issue of warping. These are through hardened and not carburized? Turned shaft?

Edited by Woody3says, 31 October 2012 - 18:07.


#66 Patrick Morgan

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Posted 31 October 2012 - 20:13

We want more pics so keep em coming!

I like you wanting to keep as close to original manufacturing as possible. With the number of pins made at the time ill bet there was a die made to quench multiple pieces at once. That would reduce the issue of warping. These are through hardened and not carburized? Turned shaft?


You may be quite right - I'm not sure, maybe a die existed. Nigel might know. The wonderful thing about Penske Cars - well Penske as a whole, was that they did everything properly. Ilmor had the same philosophy and it stood both company's in good stead.

#67 pugfan

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Posted 31 October 2012 - 23:34

shout if you're getting board of these pictures.


As in wood?

Sorry.

#68 bigleagueslider

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Posted 31 October 2012 - 23:34

We've also just got these back from heat treatment. The PC-23 uses these pins in place of bolts to attach the damper to the rocker - I assume for serviceability Nigel? Ours have seen much better days and one had lost an ear so we've had to resort to re-manufacturing them.


As many noted, the pins were designed to facilitate quick suspension adjustments. While this particular method of securing a spherical bearing & clevis linkage joint is acceptable in racing, it would not be acceptable in the aircraft industry. In the aircraft industry, it is standard practice to use a shear bolt and locknut that clamp the sides of the spherical inner race between the clevis lugs. This ensures that any sliding motion occurs at the spherical bearing race surfaces which are designed to accommodate the sliding, rather than at the interface between the pin and inner race bore which is not designed to handle such sliding motion.

Sorry if it sounds like nit-picking, but these types of little details are taken quite seriously by aircraft mechanical systems engineers. And this is after all a technical forum.

Slider


#69 gruntguru

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Posted 31 October 2012 - 23:50

I assume you mean the "sliding" that occures during rotation about the pin/bolt axis?

#70 Patrick Morgan

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Posted 01 November 2012 - 08:32

As many noted, the pins were designed to facilitate quick suspension adjustments. While this particular method of securing a spherical bearing & clevis linkage joint is acceptable in racing, it would not be acceptable in the aircraft industry. In the aircraft industry, it is standard practice to use a shear bolt and locknut that clamp the sides of the spherical inner race between the clevis lugs. This ensures that any sliding motion occurs at the spherical bearing race surfaces which are designed to accommodate the sliding, rather than at the interface between the pin and inner race bore which is not designed to handle such sliding motion.

Sorry if it sounds like nit-picking, but these types of little details are taken quite seriously by aircraft mechanical systems engineers. And this is after all a technical forum.

Slider


As Nigel mentioned, on the later cars the pins were ditched in favour of a bolt and captive nut. I couldn't say which car these were introduced on but PC-26 is certainly a bolted arraignment.

Edited by Patrick Morgan, 01 November 2012 - 08:33.


#71 Nigel Beresford

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Posted 01 November 2012 - 12:19

Bigleagueslider,

thank you for your observation about the use of quick pins in that application - I wouldn't classify it as nit-picking at all. On the face of it the pins are a nice solution - if you are a mechanic. If you are an engineer you would prefer the bolted joint arrangement you described, for all the reasons you outlined. When I joined Penske I was warned by a former Tyrrell colleague who had made a similar move to another CART team that the mechanics at Penske had a reputation for being "powerful". It took a few years to impose the discipline of making sure that we weren't making things easy for the mechanics at the expense of incremental losses in performance, or "good practice' of the type you described. A similar issue was the use of quick-pull pins for the underwing support stays. These are all very well for making it quick to remove the underwing, but the slop they added made achieving the "50 lb" deflection standard more difficult. If one can explain in sensible terms to the mechanics why you need to make their life that little bit harder then I've always found them to be receptive to the change. If you just arrogantly impose change on them without explaining your reasoning then you will get much more "push back".

Thanks

Nigel

#72 Tony Matthews

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Posted 01 November 2012 - 12:27

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Next chassis from the PC23, the PC24 - still with pins...

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The PC25, still pins...

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PC26 - Ai caramba! Bolts.







#73 Woody3says

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Posted 01 November 2012 - 13:13

Beautiful pictures! Keep it coming =)

#74 JacnGille

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Posted 01 November 2012 - 13:19

Some assorted gearbox parts - shout if you're getting bored of these pictures.

Us??????????? Never!

#75 NTSOS

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Posted 01 November 2012 - 13:22

Posted Image
PC26 - Ai caramba! Bolts.


Pretty photos!

What is the function of the gear drive mechanism?

Thanks!

John

#76 Nigel Beresford

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Posted 01 November 2012 - 14:38

Pretty photos!

What is the function of the gear drive mechanism?

Thanks!

John


Drives the rotary rocker pot mounted beneath the rocker.

#77 Woody3says

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Posted 01 November 2012 - 16:11

And the 1-2-3 adjusts ________?

#78 Nigel Beresford

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Posted 01 November 2012 - 16:25

Front anti roll bar drop link pick up points. Hence adjusts the stiffness range available for a given torsion bar / blade combination.

#79 Tony Matthews

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Posted 01 November 2012 - 18:30

Front anti roll bar drop link pick up points. Hence adjusts the stiffness range available for a given torsion bar / blade combination.

On the PC24 the options were H, M and S, on the PC25 there were only two options for the drop links, neither marked, but there is an option for the pushrod, not featured on the 23, 24, or 26. Also, there is a considerable difference in rocker sizes, the PC25 seeming to have the greatest maximum leverage, the PC26 the smallest - or at least, the smallest range of options for the drop links. Notice how seamlessly I have adopted the term 'drop link', which I couldn't remember before Nigel's post.

Edited to remove '25' from the 'not featured on' bit.

Edited by Tony Matthews, 01 November 2012 - 20:33.


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#80 Nigel Beresford

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Posted 01 November 2012 - 19:39

There's a trap here with those unmarked rockers - if you referred on the setup sheet to the "stiff" or the "soft" hole on the rocker, it was quids in that at some point in the year you'd find the mechanics had put the link in the wrong hole. Consequently we started referring to "inner" and "outer" holes, until we finally got organised and machined numbers in to the rocker on the PC26. The lesson is that it's ALWAYS a good idea to take a look around the car and make sure the right wickers, bar settings, wing positions etc. have been set, because even the very best people make mistakes occasionally.



#81 gruntguru

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Posted 01 November 2012 - 20:45

Drives the rotary rocker pot mounted beneath the rocker.

Interesting, moving the pot to the rocker. The first thought is additional shock and vibration plus cable flex. OTOH there is not a lot of travel there and it is no doubt more convenient and clean to machine a few extra holes in the rocker and reduce the number of bits and pieces mounted to the tub. I see the droop limiter got moved too. Anyone know where it went?

#82 Tony Matthews

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Posted 01 November 2012 - 20:57

Some assorted gearbox parts - shout if you're getting board of these pictures. The little splined caps cover the gearbox input and output shaft nuts which are themselves splined. They are very satisfying to work with as you can't round them off.

Posted Image
Assorted Gearbox Parts by dtperformanceltd, on Flickr


Here are two of the three items in Patrick's photograph, in place on the PC23 gearbox.
Posted Image



#83 Patrick Morgan

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Posted 01 November 2012 - 21:13

There's a trap here with those unmarked rockers - if you referred on the setup sheet to the "stiff" or the "soft" hole on the rocker, it was quids in that at some point in the year you'd find the mechanics had put the link in the wrong hole. Consequently we started referring to "inner" and "outer" holes, until we finally got organised and machined numbers in to the rocker on the PC26. The lesson is that it's ALWAYS a good idea to take a look around the car and make sure the right wickers, bar settings, wing positions etc. have been set, because even the very best people make mistakes occasionally.


Believe it or not (and I still find it hard to believe but it's true) one team I worked with managed to set a car up to turn right on an oval. I've no idea how this happened as the chief mechanic and engineer were very good with limited resources (it was a back of the grid team). The driver did one lap and radioed in that the car was trying to kill him at which point he was told to stick with it..... He came in a lap or so later visibly scared. After it was all sorted out he was told the steering rack has been set wrong which would not have fooled most driver for a second.... as it was our man went back out and all was well - to his credit he never said any more about it.

Edited by Patrick Morgan, 01 November 2012 - 21:14.


#84 Patrick Morgan

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Posted 01 November 2012 - 21:26

http://img18.imagesh...5det001copy.jpg

Nigel, this photo is really getting me confused. It looks as if the car is fitted with something between the 3rd spring the PC-23 was fitted with and the hydrobump system I recall fitted to PC-26 when I was in Reading. I can't figure out how the rockers are coupled to it though - is there something missing. I seem to recall hydrobump being "link-less" i.e. a hydraulic coupling but it's a long time ago and I was doing engine stuff. I may have got this very muddled.

#85 GSpeedR

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Posted 01 November 2012 - 21:30

Interesting, moving the pot to the rocker. The first thought is additional shock and vibration plus cable flex. OTOH there is not a lot of travel there and it is no doubt more convenient and clean to machine a few extra holes in the rocker and reduce the number of bits and pieces mounted to the tub. I see the droop limiter got moved too. Anyone know where it went?


Rotary pots tend to better handle low displacement, high freq inputs than their linear counterparts (especially when down-geared).

Edited by GSpeedR, 01 November 2012 - 21:33.


#86 Patrick Morgan

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Posted 01 November 2012 - 21:39

Slightly off topic but not by too much - for anyone that hasn't seen it we ran our PC-26 at Rockingham last year which was great. Bear in mind this was a demo so it's not flat out. Gary Ward was driving and did 15 laps hitting 205mph on the straights which is slow by racing standards but not bad for a demo. It made me nervous enough but he's a very safe pair of hands.



#87 Nigel Beresford

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Posted 01 November 2012 - 21:39

Interesting, moving the pot to the rocker. The first thought is additional shock and vibration plus cable flex. OTOH there is not a lot of travel there and it is no doubt more convenient and clean to machine a few extra holes in the rocker and reduce the number of bits and pieces mounted to the tub. I see the droop limiter got moved too. Anyone know where it went?


Swings and roundabouts really - it's easier to just drill off the holes in the rocker on the CNC mill at the manufacturing stage, and it's a tidier visual arrangement, but if the pot goes down (as rotary pots are wont to do) then it's more of a faff to change it than the earlier arrangement. On the other hand, the earlier arrangement required inserts in the tub (okay, not a big deal but it would add some time and processes to the tub manufacture), and the need to drill and tap these inserts once the tub was being built. Knowing John Travis (who handled the suspension detailing, although it was Nigel Bennett's car) it's probably the "tidier visual arrangement" that was the main virtue.

There is an abutment feature on the rocker itself (at the bottom edge of the frame in Tony's photo) which I think was meant to do the droop limiter job, but there is no stop shown in the picture and to be honest I can't remember for sure what we had. I want to say it was a small kidney shaped block. Patrick has a PC26 - he can probably answer definitively.

Note the low friction bearing at the pushrod pickup. This was introduced by JT, along with various other bearings at the spring seats etc, to minimise stiction in the suspension.


#88 Nigel Beresford

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Posted 01 November 2012 - 21:40

Rotary pots tend to better handle low displacement, high freq inputs than their linear counterparts (especially when down-geared).


They are also less susceptible to collateral damage from dropped tools etc, and are a bit easier to package.

#89 Patrick Morgan

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Posted 01 November 2012 - 21:47

Rotary pots tend to better handle low displacement, high freq inputs than their linear counterparts (especially when down-geared).


They don't like vibration much though..... the gearbox POT's failed regularly (as I recall - Nigel may put me right) despite an extremely well thought out mounting system. With the Reynard and Lola cars we went over to a load cell in the gear linkage called a bang switch. The down side was that the effort the driver had to put into a shift for the ignition cut to trigger was slightly higher and those gearboxes were high effort anyway.

We went over to LVDT's on the throttle which cured the vibration problem but created another dilemma as the amplifier for an LVDT has to be kept at roughly a constant temperature... about the only place that works is in the nose. Not ideal for anyone.

#90 Nigel Beresford

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Posted 01 November 2012 - 21:48

http://img18.imagesh...5det001copy.jpg

Nigel, this photo is really getting me confused. It looks as if the car is fitted with something between the 3rd spring the PC-23 was fitted with and the hydrobump system I recall fitted to PC-26 when I was in Reading. I can't figure out how the rockers are coupled to it though - is there something missing. I seem to recall hydrobump being "link-less" i.e. a hydraulic coupling but it's a long time ago and I was doing engine stuff. I may have got this very muddled.


Yes, I was waiting for someone to comment on this. There are parts missing. There was a pivoting cross-link which was pulled by drop links from the rocker. The car in the pic was being built for oval usage (see the FARB), which didn't employ the damped monobump - I expect the build shop boys just fitted the front monobump system to check fit it when Tony took the pictures. For sure that's not something we'd have wanted shown in his cutaways.

#91 Patrick Morgan

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Posted 01 November 2012 - 21:52

Swings and roundabouts really - it's easier to just drill off the holes in the rocker on the CNC mill at the manufacturing stage, and it's a tidier visual arrangement, but if the pot goes down (as rotary pots are wont to do) then it's more of a faff to change it than the earlier arrangement. On the other hand, the earlier arrangement required inserts in the tub (okay, not a big deal but it would add some time and processes to the tub manufacture), and the need to drill and tap these inserts once the tub was being built. Knowing John Travis (who handled the suspension detailing, although it was Nigel Bennett's car) it's probably the "tidier visual arrangement" that was the main virtue.

There is an abutment feature on the rocker itself (at the bottom edge of the frame in Tony's photo) which I think was meant to do the droop limiter job, but there is no stop shown in the picture and to be honest I can't remember for sure what we had. I want to say it was a small kidney shaped block. Patrick has a PC26 - he can probably answer definitively.

Note the low friction bearing at the pushrod pickup. This was introduced by JT, along with various other bearings at the spring seats etc, to minimise stiction in the suspension.


Exactly, there is a feature on the rocker to act as the drop stop. If I get chance I'll take a photo tomorrow. The PC-26 clearly shows a big effort to get friction down on the suspension. It's really very impressive short of going to torsion bars and flexures. I have a hard time keeping the muck out of the spring platform bearings Nigel!

Edited by Patrick Morgan, 01 November 2012 - 21:52.


#92 Patrick Morgan

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Posted 01 November 2012 - 22:01

Can I just say that the gear under the rocker pivot on the PC-26 is not located in any way and it a real bugger to get properly orientated when you do the rocker nut up - you can't hold it in place, the friction is too great. you have to experiment for a while to get the right loose position to get it in the range of the POT when tight.

This is my only gripe with any Penske car ever. Everything else is just wonderful (with the possible exception of trying to figure out John Favor's re-wiring).

#93 Patrick Morgan

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Posted 01 November 2012 - 22:09

Yes, I was waiting for someone to comment on this. There are parts missing. There was a pivoting cross-link which was pulled by drop links from the rocker. The car in the pic was being built for oval usage (see the FARB), which didn't employ the damped monobump - I expect the build shop boys just fitted the front monobump system to check fit it when Tony took the pictures. For sure that's not something we'd have wanted shown in his cutaways.


This is the genius of Mr. Matthews - he always knew how to leave sensitive stuff out. His 265A cutaway misses out all the guide vanes in the water jacket for example - a real Mario tweak at the time. The mass dampers for the cams never appear in any of his works as far as I'm aware. They are really neat pieces - you just have to remember to de-mag them after crack testing or you could end up in a mess really fast.

#94 Nigel Beresford

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Posted 01 November 2012 - 22:14

I understand and agree it's definitely a fair comment about the pot drive gear, though I hadn't heard it before. I guess our mechanics suffered in silence!


#95 Patrick Morgan

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Posted 01 November 2012 - 22:20

I understand and agree it's definitely a fair comment about the pot drive gear, though I hadn't heard it before. I guess our mechanics suffered in silence!


In fairness you don't have to tighten it very often. I guess the rockers didn't get taken off more than once before a race meeting if that. One of the really neat features of the Mercedes DTM car we restored a couple of years ago was that the rocker pivots were sealed to stop dirt ingestion. There was a small increase in friction I'm sure but the wheel rate on that car was such that it probably made very little difference in real terms.

Nigel - PC-26 is a great car just like all the others. I shouldn't complain at all. I love working on them any time I get the chance.

Edited by Patrick Morgan, 01 November 2012 - 22:22.


#96 Tony Matthews

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Posted 01 November 2012 - 22:46

This is the genius of Mr. Matthews - he always knew how to leave sensitive stuff out. His 265A cutaway misses out all the guide vanes in the water jacket for example - a real Mario tweak at the time. The mass dampers for the cams never appear in any of his works as far as I'm aware. They are really neat pieces - you just have to remember to de-mag them after crack testing or you could end up in a mess really fast.

Dunno about genius, I was told what not to show! The guide vanes - if I understand this, it is what I thought were liner supports - was one, and a couple of features that are visible on the drawings but didn't make it to the finished artwork. Even now I'm not sure if I should mention them... The dampers, of course, were not present on the early 265As, and if you look at the 265B drawing you can see them as outline, un-detailed blanks. My hope was to add them as white line 'ghosts' on the painting, as it was the detail that Paul and Mario were twitchy about, not the fact that they existed. I photographed them, but have never shown them. On the first Ilmor V10 I used that approach. On the Ferrari 049 engine, I wasn't allowed to photograph, or even look at, the dampers!

On the PC25 cutaway most detail infront of the front spring/damper units is hidden by a CF cover, which was not in place for most of the photographs, but appeared later. As Nigel says, bits are missing. I think the only Penskes that I saw completely finished and in one piece were the PC6 and PC20.

Edited by Tony Matthews, 01 November 2012 - 22:46.


#97 desmo

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Posted 02 November 2012 - 01:52

What a treat to hear the shop talk! It adds a lot to the illustrations. This is brilliant from a fly on the wall perspective, thanks.

#98 gruntguru

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Posted 02 November 2012 - 03:56

:up: Absolutely - keep it coming!

#99 Tony Matthews

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Posted 02 November 2012 - 15:32

Posted Image
Re: post 61, here is a photo of the air jack, or the top of it, in situ, although this is in a PC25, but the side moulding and access panel are very similar.


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#100 Tony Matthews

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Posted 02 November 2012 - 15:40

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The CF cover - I wonder what's under there... Also, I've realised why the PCs 24 and 25 had such long rockers, it was to accommodate the extra drop links to the third spring/damper/top secret bits.

I seem to remember that on the Williams FW14B the trick suspension actuators and Moog valves on the tub top were hidden from prying eyes by a rectangle of black cloth held in place by Velcro strips. Not as neat as the Penske cover, but Williams probably had a bit less room.

Edited by Tony Matthews, 02 November 2012 - 15:45.