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Actually the old bugger Mezger is 90 today!

 

I guess we can't be too hard on him, that was the fashion of the day.

(Ducati's Taglioni made the same mistake even later and unfortunately held on to wide valve angles and the hemispherical concept to the end. (Although he did dabble in some beneficial squish and offset inlet port created swirl)  Fortunately guys like Dr Gigi Mengoli (http://www.thelasturl.net/1000DStech/1000DStech.htm , http://www.automototech.com/node/39 ) and Angiolino Marchetti, ex Ferrari, took Ducati engines into the front row of the modern world after Dr Bordi kicked them along a bit by introducing some Cosworth/Ford DFV combustion chamber thinking.)  

 

 

 

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18 hours ago, Peter M said:

Interesting modifications to a 3.2, many that you don't see done often such a the wheel fans, KW suspension and the 964 windscreen and seal.  Worth a look.

http://forums.pelicanparts.com/porsche-911-technical-forum/1004330-1987-3-2-carrera-do-list.html

 

 

I've been following this build, it looks great!  Amazed how well the turbo fans suited the narrow body.  And the KW shocks looks on point as well 🤙

 

Haven't heard of many others using the 964 screen and seals.  

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POST UNDER CONSTRUCTION - I'll finish after I get the dashboard back in my XJ6 and go to Uralla for a pie

 

What Would a Modernised 3.2 Engine Specification Be?

Or what would I think I'd do to my next 3.2?

Since the majority of 3.2's seem to be in the 180,000 to 250,000km range now and are likely due for a set of valve guides, let's assume the engine is coming out. (Grant at Autohaus reckons the 3.2's wear the guides quicker than the rest due to excessively long startup enrichment to kick the cat off quickly.)

It's probably has a few oil leaks to resolve.

Couple of the cam lobes and followers are pitted

You'll probably want to have it on historic registration so the engine modifications need to be subtle to pass the visual inspection.

The pistons and cylinders will be still good and in specification.

It hasn't got cruise control and it would be a handy feature for those tedious and heavily policed highway runs which seem to be more and more our lot.

You're not swimming in money so every dollar has to deliver.  No flights of whimsy like the red car. 

 

Exhaust

Standard heat exchangers but with a O2 sensor welded into each header

Cat bypass tube

Secondhand 1 into 1 or 1 into 2 muffler like a Monty, M&K or Dansk Motorsport

 

Intake

AFM delete tube with boss to mount Air Temperature Sensor

Airbox lid drilled discretely for better flow

Throttle Position Sensor to replace the existing throttle position switch

Modern 4 hole Bosch injectors

Replace all the rubber fuel hoses

 

Heads

Standard reconditioning with new valve guides and possibly new valves.

Reuse existing valve springs if still serviceable

Machine additional plug holes in heads = $690

Set of 964 lower rocker covers = $250  (Or bore 3 holes in each of your existing covers for nothing if you have the equipment)

964 rocker cover seals = $60

964 cams as these I understand still provide sufficient valve to piston clearance with standard pistons

Set of new rockers as they're probably cheaper than reconditioning the old ones.

 

Ignition

12 x Bosch 0986 221 024 @ $65 each = $780  You could also use a 964/993 distributor but why would you when CoP is cheaper and less grief (no broken belt, worn shaft bearings or high tension leads to replace) if you're using a modern ECU anyway?

12 x BCPR7ES = $80

12 x RSR plug holders = $90

36-1 or 60-2  tooth crank wheel

Hall sensor

Cam position sensor

 

ECU

Haltech Elite 750 ($1495) or 1500 ($1995) for DBW and cruise control

Link Storm ($1595) or Extreme ($1795) 

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On 06/12/2019 at 10:39, Uncle said:

Why such low resolution?

Martin,

I investigated this when I was about to buy a 36-1 Clewett set up and found that the benefits of extra resolution weren't definitive.  Except for some vague comments that extra resolution could give improved idle quality (read that as emission performance as well) but could also cause unreliable triggering at (extreme) rpm's, there was little guidance available. Neither of which are an issue with a Mezger build.

(Yes, I've double checked and I actually have a 36-1 not a 30-2 as I have been previously posting due to my general state of confusion.  I've corrected my previous posts as a result thanks.)

I couldn't even distinguish a clear trend with engine manufacturers.

From info in the Haltech ESP sensor setup drop down menu:

Evo 9's have 2 teeth on their crank wheels (but actually sense the rising and falling of each tooth so effectively 4 teeth)

RB25's have 6

Honda B18C have 24

GSXR1000 K3 to K8 have 24-2

Nissan VR38DETT have 36 with 3 lots of 2 teeth missing

As I say, no clear trend!

 

When I first started out I was planning on using the standard 3.2 flywheel with 129 + 1 teeth but Haltech were unable to confirm a Elite would cope with this. 

Consequently I bought an aftermarket crank wheel that I knew all aftermarket ECU's could deal with.  However, I could have easily bought a 60-2 as an alternative.

 

 

What I would do differently next time is use a bolt with a smaller head in the end of the cam to improve the resolution of cam position sensor (I just used the bolt Clewett supplied) and have greater offset between the missing tooth on the crank wheel as I sometimes get a low level error message from the Motec.  In practice not an issue but would be a nice "do it 100% correct" tidy up.   Andre touches on this issue in this webinar transcript:

https://www.hpacademy.com/previous-webinars/148-trigger-systems-explained/

Also very good discussion here from Scott on the best working relationship between the cam angle and the crank sensors:

 

 

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Drive By Wire

 

My ears pricked up towards the end when Tuningfork started talking about accelerator pedal sensors.  He recommends for cars with accelerator cable not replacing the existing accelerator pedal because it's so hard to get a e-pedal fitted in an old car so it feels right but installing a Honda Accord 2003 to 2007 accelerator pedal sensor to provide the necessary position information to the ECU.  From what I can see, cheap and probably easier to mount than any others I've seen.

aWexICK.jpg

And readily available off Ebay:

https://www.ebay.com.au/itm/Accelerator-Pedal-Sensor-37971-RCA-A01-For-2003-2007-Honda-Accord-2-4L-3-0L-AU/372821818145?fits=Model%3AAccord|Make%3AHonda&hash=item56cde97b21:g:DaoAAOSwJYVduSmg

 

The APS used on some Nissans and Hondas also look usable to:

yyPoThG.jpg

Also cheap and readily available too:

https://www.ebay.com.au/itm/New-Black-High-Quality-Accelerator-Pedal-Control-Position-Sensor-For-Nissan/202746399410?fits=Make%3AHonda&hash=item2f34a08ab2:g:KxwAAOSwKF1dQRKj&autorefresh=true

Wiring diagram:

https://www.raceworks.com.au/wp-content/uploads/2019/08/LR-RWORKS-DATA-APS-501.pdf

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On 06/12/2019 at 10:39, Uncle said:

Why such low resolution?

There is little real world difference once you get over 12 teeth on the crank. The ECU projects future events for fuel and ignition in time from each real tooth which acts as a fixed angle reference for the crank. You will only see transient differences with very high rpm acceleration rates. The more teeth the smaller the transient error but older systems with less teeth often have them strategically placed to minimise this error. With rpm accelerating rapidly say for a down shift blip the ign timing will be ever so slightly retarded with the amount dependant on how far after a crank tooth the spark was programmed to be. The bigger the gap between teeth the longer the possible delay in time from that tooth to the spark angle.

For best performance in any application stick with 36 to 60 teeth on the crank. Some older engines from the 80s to 90s could benefit from an upgrade as will anything that crank triggers from the cam.

I will also add that with a -2 setup you never want the spark to happen in the -2 section of the trigger wheel as the potential projection in time from a real tooth to the spark could be 3 times longer than for other cylinders so your 36-2 tooth wheel is no better than a 12 tooth wheel for two of the cylinders. 

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  • 2 weeks later...

Interesting discussion that covers a lot of contemporary EFI ground.  They just happen to be talking about a new release Haltech product:

 

 

Don't know anything about Andy except he has a huge fan club and it was considered a canny move by Haltech to make him an offer he couldn't refuse. 

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7 hours ago, clutch-monkey said:

nexus r5 is good but seems aimed at top end drag racing in the states etc. but i look forward to the benefits trickling down to the rest of the range

Sam,

That was my first thought too but thinking about how convenient it is to have all the "boxes" consolidated into one has to be a considerable time and space saver advantage.  On my car for example, the R5 would do away with the separate twin O2 sensor controllers, the relays and fuses for the ignition coils and fuel pump and the 3D printed box to mount all this and the ecu in.  I also like how the PCM gives you real current draw data and has very sophisticated over current management.

I do agree I don't need 18 fuel injector drivers! 

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1 hour ago, Peter M said:

Sam,

That was my first thought too but thinking about how convenient it is to have all the "boxes" consolidated into one has to be a considerable time and space saver advantage.  On my car for example, the R5 would do away with the separate twin O2 sensor controllers, the relays and fuses for the ignition coils and fuel pump and the 3D printed box to mount all this and the ecu in.  I also like how the PCM gives you real current draw data and has very sophisticated over current management.

I do agree I don't need 18 fuel injector drivers! 

There are a few good reasons not to put everything in the one box. First is heat generation especially if a PDM is integrated. The box needs to be big and usually heavy enough or require special cooling provisions to dissipate the heat which is a penalty if you don't need all the features/capabilities. Second is the upfront price will be higher. Again not an issue if you use most of it capability but a big problem for many who may want to expand and grow the system as the budget allows. Third is failure of any of its functions especially out of warranty. It is much cheaper to replace small parts such as a lambda controller than a full on single electronics box. 
 

If you have an ECU and other parts in a closed box I would monitor the temperatures closely. Same if just stuffed under a carpet etc.

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15 hours ago, Peter M said:

Sam,

That was my first thought too but thinking about how convenient it is to have all the "boxes" consolidated into one has to be a considerable time and space saver advantage.  On my car for example, the R5 would do away with the separate twin O2 sensor controllers, the relays and fuses for the ignition coils and fuel pump and the 3D printed box to mount all this and the ecu in.  I also like how the PCM gives you real current draw data and has very sophisticated over current management.

I do agree I don't need 18 fuel injector drivers! 

i suspect on a road car the annoying part of having it all in one box is that if something fails the whole box has to go back to be fixed. modular boxes at least you can send or replace the specific broken part?

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  • 2 weeks later...

A bit more discussion on the speed of combustion by Kevin Cameron, who does it better that anyone else I think and some background to why it's important for us and why we do certain things to our old engines like twin plugging:

https://www.cycleworld.com/how-fuel-efficiency-and-fast-combustion-are-related/

https://www.cycleworld.com/story/bikes/compression-ratio-cylinder-size-and-engine-speed/

 

 

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Air Conditioning For Pre-964 911's

I frankly can't understand how anyone can own a car without air conditioning and expect to drive it regularly.  From what I can determine with 3.2's and the like there are a couple of obstacles to overcome to having acceptable air condition performance:

Lack of Vent Area - Especially a problem in pre-86 cars. However irrespective of bigger later vents, they still need to be supplied with adequate cold air which leads to...

Lack of Flow Volume - Whilst the evaporator blower output itself is acceptable, the restrictive ducting, along with restricted vent area doesn't provide much comfort.  Often there are brags on the forums by people posting they have achieved vent temperatures of only a couple of degrees.  However they fail to make the connection that the vent temperatures are so low because they're pumping through such meagre air volumes. They also fail to make the connection that no one can really stand being jetted with artic air to only one or two small points on their body anyway!  Modern cars are comfortable because they pump out large volumes of air at a temperature that doesn't cause discomfort (ie vent temps of about 7 degrees). 

With the 3.2's, Porsche changed the ducting over the course of the model run to improve fresh air performance of the centre vents.  Unfortunately I think this may have caused a reduction of flow from the air conditioner due to less direct plumbing.  

Poor Condenser Performance at Low Speeds - Since the main condenser is dependent on the engine fan, getting adequate heat exchange in stop start traffic is a challenge

Originally No Consideration for Air Conditioning - Being designed in 1964 has created the above plus some other challengers with regard having space for larger vent ducting, additional condensers etc.

Set up for R12 - Now unobtainable

 

How to fix?

There are many threads on this topic but few, actually none get to a solution that ticks all the boxes to a standard we would expect in a modern car.  Probably the best thread on this is below but it's still doesn't get there but offers up lots of insights from Mr Griffith in particularly and puts to bed a few myths:

http://forums.pelicanparts.com/porsche-911-technical-forum/176468-griffiths-fender-condenser-dimensions-7.html

This is also a useful thread as it has details of the hose lengths(albeit a LHD car) and photos of 993 condensers fitted to the rear wheel well of a G series:

http://forums.pelicanparts.com/porsche-911-technical-forum/523204-barrier-hose-length.html

A good sensible approach here:

 

http://forums.pelicanparts.com/porsche-911-technical-forum/288251-obligatory-32f-ac-vent-image.html

 

 

 

 

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