Rebuilding a 962 motor

[Carrera3.5L]

Okay, as promised I went down to Neil's shop today to try and lend a hand and snap some pics. This motor is going together quickly and efficiently, it needs to be done by Friday night and on the dyno hopefully sometime next week. Here goes...

930 guys? Does the case below look familiar? It should, it's simply a 930 case that has been extensively machined and is now modified for use in a water-cooled "C" motor!



Authentic 962 cases are VERY difficult to source and are SILLY money if you find one. It is much cheaper to buy a 930 case, spend a few thousand dollars in machine work and start from there. A short-cut perhaps? Nope. This was done in the heyday of GTP in the '80's as well (right from Andial/PMNA), Helidoc's case was a converted 930 unit when it was originally built by Andial and used in competition by Vern Schuppan.



View from the underside of the case and oil line that goes from the magnesium oil pump to the twin oil coolers located on each side of the motor.



View of the cylinder head studs which are special units unique to the 962C engine. Titanium rods that are shot peened rest on o-rings while waiting for the pistons to be installed. The Ti rods were also oftentimes polished while at Andial, but these weren't.



Another view of the underside of the case, note the extensive use of safety wire. This extra attention to detail is necessary, with the high cost of parts (if you can find them) the last thing you want is something to work loose and potentially grenade the motor.



This motor is going together in "chunks", as Neil has already subassembled various pieces. Above is one bank of one-piece water-cooled cylinders/heads (remember they are welded together) along with the water manifold inlets and outlets together and ready to go! The cylinder/head connection is a common source for cracks/leaks, which is why Neil has a special cylinder liner/sleeve that he offers. Water-cooled 962C cylinders/heads were about $6,000 EACH back in the glory days, I don't know what they cost now. These check out fine and Neil didn't find it particularly necessary to use his design in this particular application.



Intake valves measure 35mm and exhausts are 30.5mm. Note the central spark plug location, darn water-cooled motors!

I don't know if there is a limit on how many pics per post, so I'll start a new post and continue...

Ralph

[917956962]

This thread LIVES! Thank you for the pictures. Excellent stuff!

[47silver]

thanks for your efforts these are great photo's

[Carrera3.5L]

Here's an absolutely terrible image of a 962 piston with a wrist pin clip (but this is actually the best image I took), I am a terrible photographer so bear with me!



962 pistons had a "frosted" finish up top but this finish quickly wears/flakes off, primarily due to detonation. These pistons have been treated to a ceramic coateing to try and lessen the effect.

As I mentioned in an earlier post near the beginning of this thread, the 95mm pistons used in these motors were available in 9:1, 9.5:1 or 10:1 compression ratios. We'll measure and see what these end up at. Since this is now a vintage "race" motor the lower compression ratio will probably better for the motor's long-term reliability where every last horsepower is not necessary nor can be exploited. The new owner is apparently a racer at heart and will run the car, it will not be a museum showpiece collecting dust!

Here are a couple of pics of a wheel housing for one bank with int. shaft & cam gears inside:





This was another trouble spot with these motors, note the direct oil feeds. Sometimes the oil feed moves offline and causes the shaft and/or needle bearing inside to freeze (meanwhile the crank is still turning) and things go bad from there. There was one motor at Andial back in the late '80's that when torn down simply spilled its guts onto the floor. Neil has strenthened this area with his own design to help eliminate this problem as well as make servicing much easier and cost effective. Before, you pretty much had to purchase all new parts...I'll try and explain this better with the 956 motor that Neil also has, as this motor is all in parts at present and I can take pics of the parts and show what is happening inside.

That's about it for pics at present, tomorrow the pistons will be installed along with the cylinders/heads. Neil is going to work on it all day tomorrow and I will join him after hours and lend a hand. The goal is to have the long-block done and work on the injection side. Depending on how long it takes, I may not post any pics tomorrow...

I've shown/told people the obvious differences between a 956 water-cooled head/air-cooled cylinder and 962C water-cooled head & cylinder in other threads, below are some pics of a 956 head/cylinder just as a comparison:







The dead giveaway between a 956 and 962C is the fins on the 956 cylinders, which the 962C motor does not have.

Here is a pic of a 956 piston, I tried to show the small recess in the center of the piston which lowers the compression. Remember, the 2.8L 956 was the predecessor to the 962C and used the older Kugelfischer "mechanical" injection while the 962C motor used the more modern (at the time) Motronic 1.7 engine management. This allowed for more precise fuel/spark delivery, a higher compression ratio being one of the benefits...




Finally, a titanium rod for the 956 engine rebuild that will follow this 962C project. Note that this rod has been polished...



I think I forgot to mention earlier, but this 962C motor is a 3.2L using the longer 74.4mm stroke crank. The extra torque to mitigate turbo lag out of the corner will be appreciated...

Ralph

P.S. - In addition to the 962C and 956 motors, Neil's also got a 4-cam 904 motor he's building for a customer as well...One project at a time...

[Carrera3.5L]

Darn, I just realized that I screwed up the image of the 962C piston...now I'll subject you to all of them...







Ralph

[Don Settergren]

I feel like I just visited an art studio with a highly knowledgable guide. THANKS for keeping this thread alive. Can you acquire audio during the dyno run? Sorry, I'm getting greedy.

[VZ935]

Cool stuff... here are the ti rods and Andial engine stamp on the motor in my 935 M16 .. I opted to take the ti rods out but they were polished as indicated by the paperwork I got from Deiter on my motor...

[sand_man]

SPEECHLESS!



Thanks for your efforts, Ralph!

[sand_man]

For those that are curious, my opinion of Neil Harvey (Performance Developments) is that he is the ABSOLUTE sage and shaman of the Porsche race engine...especially when a turbo is involved!!!! For someone of his caliber (he's also dabbled with F1 engines), he's also a damn nice guy...no ego trips and very humble!

When Neil had my 930 parts, I wanted so badly to make the trip from NC to CA to visit his shop and watch the machining process. I can tell you that his attention to detail and the cleanliness of my parts were nothing short of surgical! Never seen anything like it. When I got everything back, it was literally just assembly work for me...all the measuring, specing, cleaning, and tolerances had been checked and reset.

No matter what the problem might be, he has a well thought solution. I only wish there was more $$$$ in my budget to employ more of his skills and custom products.

[Carrera3.5L]

Neil made HUGE progress today, by the time I got there late this afternoon he pretty much had the long block sewn up. However, he was nice enough to take some images as he went along with his camera, he will make me a CD-ROM with the images to go along with mine...

Once I get it from him, I'll come back here and "fill in the blanks"...

Compression ratio measured out at 9.2:1 with a deck height of just over 1 mm. The same camshafts that came out of the motor went back in, as the customer wants to keep it as original as possible and not toy with different cam profiles, at least not yet! I won't release the cam timing as this is proprietary info that Neil doesn't want to disclose in a public forum. I can say that the intake cams have 9.3mm lift and 276° duration at .5mm and the exhaust cams also have 9.3mm lift with 288° duration at .5mm.

Here is Neil with one intake assembly on:




Here is a close-up image:



Notice the fuel filter? Probably some expensive and trick unit, right? Nope. Bosch part number 0.450.905.003, which is what mid-70's 911's and 924's used.

Peering down the intake tract:



Here are a couple of images with the water pump housings fitted:





Note how the water pumps run off the intake camshafts? 956's and some 962C's had the water pumps mounted low and ran off of the exhaust camshafts. When Porsche revised the bodywork of the 962 in an effort to create more downforce, they needed the room down low and thus moved the water pumps up to help facilitate...the motor could be ordered in either configuration.

I mentioned earlier, but there were many a visitor to Andial's engine shop that saw a C motor on the stand and thought those were cool looking turbochargers...

View of one of the intake plenums with the famous "Prepared by Andial" sticker that adorned EVERY 962 intake plenum (air or water-cooled) that left the shop...




I'll stop here temporarily and take a break! Be back in a few minutes after my son goes to bed!

Ralph

[Carrera3.5L]

Okay, let's go on with it...lots still to show and comment on...

In this image you can see the strip of paper taped to the plenum that provides some numerical information. Helidoc took a close-up of the numbers on an earlier page of this thread...



These offset numbers are what are located on both fuel pressure transducers and the oil pressure transducer. Remember, the electronics on this motor think that there is essentially 2 motors, as each bank is separate. The numbers are what are located on the transducers and allows for conversion from mechanical to electronic. These sensors would normally be hidden away and difficult to read, the note on the plenum makes it easy for the technician to read and program the correct numbers.

Here is an image (albeit fuzzy) of one of the fuel pressure transducers:



Unfortunately, you can't read the numbers on it but trust me when I say they are the same as what is typed on the paper...

The single oil pressure transducer (in the left foreground):



Here is a close-up of some of the ignition components. Interestingly, an inductive wasted spark system was employed on the 962C, why I don't know but there must have been a reason Porsche engine designers used it...



Neil loves to ditch the old and obsolete Motronic 1.7 system with all its balky sensors and harnesses in favor of his own modern EFI set-up. This allows for the motor to run as a complete unit, rather than as two separate banks (he "bridges" the intake plenums) and not only does the motor perform much better, it also really cleans up the wiring around the motor. This customer wants the motor to stay original (probably for resale value) but the option is out there and works well. The cost? $35,000 complete and turn-key...

Here are a couple of pics of where the two turbo scavenge pumps (run off of the exhaust cams) mount:





Here is a close-up shot of the mounting area and of a scavenge pump:





Time to go to the next post...

Ralph

[Carrera3.5L]

Guys, I'm sorry but I just spent the last 30-45 minutes posting more images and typing more notes and when I went to hit submit it said I have too many images and I lost everything! I'm too tired to do it all over again right now, I'll try again tomorrow evening or over the weekend...

Ralph

[Shuie]

Thanks, Ralph. This is cool stuff.

[WERK I]

Originally posted by Carrera3.5L
Guys, I'm sorry but I just spent the last 30-45 minutes posting more images and typing more notes and when I went to hit submit it said I have too many images and I lost everything! I'm too tired to do it all over again right now, I'll try again tomorrow evening or over the weekend...

Ralph

Ralph,
That's quite alright---------we're not going anywhere.

Thanks for all your effort.

[sand_man]

Many thanks indeed, Ralph. Hey is it all possible that Neil worked on this engine before (when it was new) during his years at Andial? Just curious. I'm not exactly certain on what Neil's career timeline is.

[911 tweaks]

Ralph, words cannot express the appreciation I am sure all that are following this thread are feeling and wish to tell you!
Great job and thanks for all of your efforts!!
Bob

[Mike Andrew]

Ralph,
I second 911 Tweeks.

Thanks

[Carrera3.5L]

Thanks for the kind words guys, but I actually enjoy doing this or I wouldn't do it. I worked around these engines for 5 years on a daily basis a long time ago when I was very young and naive, so they do have a special place with me although the C motor wasn't very successful in IMSA relative to its air-cooled predecessor (primarily due to an increase in quality competition from the likes of Jaguar, Nissan & Toyota). I have tons of regular photographs that I took during the time period, but unfortunately this was long before the digital camera age....

It is amazing to me how much people are into the 962 long after its demise, and astounding that many of you have never seen or heard them in action but just have read about them in books or on the internet. I guess I really didn't appreciate it back than...but the car actually wasn't that good relative to the competition (it was TERRIBLE under braking) and wasn't well suited to the slower, tighter US tracks where downforce is important. The motor also left alot of power on the table due to politics inside and outside of Porsche, but those are stories that won't be told on a public forum, I don't want to burst people's bubbles about what really went on...

Okay, let's get back to the ex-Helidoc motor:

Let's start with the outcome when you drop a valve in a 962C motor (this isn't Helidoc's just to clarify):







Not pretty, is it...

Here is a pic of the throttle linkage installed on the motor:



Here is another side view of the motor. Note the oil filter housing next to the water pump housing. In Porsche's infinite wisdom, the screen type filter could only be changed by removing the water pump first...



Here is a pic of the alternator before being installed (where the fan would normally be on an air-cooled motor). There were a couple of different alternators that were used, from memory (so don't take it as gospel) they were 80 amp or 120 amp units, their use depending on whether it was a sprint or endurance race. The higher rated alternator was used for the endurance races where lights would be necessary...Alternator problems cost the Dyson team the 1991 24 Hours, as they were the fastest car during the night but had charging problems throughout the race that killed them and they eventually retired near sunrise. It worked out though, as Dauer's 962C with the Andretti's and Joest's 962C with Bob Wollek primarily at the controls when it mattered had a good duel which Joest won at the end after Andretti's clutch assembly locked up during a pit stop and wouldn't move with a couple of hours left...



I better be smart and start another post before I lose all this as well...

Ralph

[Carrera3.5L]

Here is a pic of Reid Washbon's headers for the 962C. Reid did (and still does) the exhausts for many of Porsche's high level race cars and at the time of the 962C was also doing the exhausts for All American Racers (Gurney's team running the Toyota Eagle program) that were a hop, skip and jump away from Andial's shop and NPTI (Nissan Performance Technology Inc) who were running the GTP-ZXT and NPT-91 cars first from El Segundo and later from their then state-of-the art facility (they were the first with a wind tunnel) in Vista.

Reid is still crafting headers (these days primarily for CART & IRL teams), and is literally 50-75 yards from Neil's shop...we SoCal guys truly are blessed with highly talented individuals and firms, the only places that are probably comparable in motorsports are Indianapolis and England...



Note how short they are and also how small the diameter is for a high-horsepower race engine. This really helped in throttle response out of the corners, where the car's lack of downforce and the motor's low-end torque was an achilles heal that really put it in a bind against the grunt of the V8 and V12 normally aspirated cars, especially in temporary street races. The primaries are only 41.5mm OD (about 1.65") with the collector at 47mm OD/44mm ID. Who says you have to have huge diameter headers to make serious horsepower?

Below is a pic of one of the Garret turbo housings. You've all probably seen the KKK logo on the sides of various 962C's, and the Group C cars in Europe that were built by Porsche did use KKK (now 3K or Borg-Warner) turbos until almost the very end of Group C but over here in IMSA and the All-Japan Sports Prototype Series the 962C (and the air-cooled, single turbo 962 motor) used Garret turbos. Garret was/is just up the freeway from Andial and had a dedicated man to service the Porsche account so he was at the shop often.

These particular turbos and wastegates are being rebuilt before going back on the motor. Also note that this motor used a turbo for each bank in tandem, they were not sequential as the 959 road car used that was available around the same time...



Here is a pic of the 240mm clutch components (note the Sachs riveted 4-puck disc):



As mentioned earlier, the Motronic 1.7 engine management was state-of-the art at the time (it had knock sensors for one!!! (note sarcasm)) but it didn't work all that well. Because it essentially broke the motor in half (and sometimes one side of the motor ran slightly differently than the other) the computer was constantly trying to adjust and figure out what was going on to compensate for the other side. The end result is that often the motor just didn't run as crisply as it should/could, and could generally be felt on the dyno long before going into the chassis.







The ecu is HUGE in comparison to modern computers and this was mounted where a passenger seat technically would have been in the car, which is the left side of the car since the driver sat on the right side. This was of course because of the track configurations in Europe...

The silver box that is mounted on the main ecu is the knock control box...

The motor is actually all done and ready to go on the dyno. Neil was also kind enough to send me pics of the case split open with the crank and oil pump assembled, of the valve train assembly, the pistons installed and pretty much everything else that I missed. I'll try and get those up over the weekend or early next week at some point...

To answer the question of whether Neil worked on this motor when it was used in competition, I don't know. The motors were serviced on a rotational basis by 4-5 different techs, a tech was not assigned to any particular teams engines but were assigned to a particular team during a race weekend. The motors were supposed to be hands-off to the teams, they were only supposed to remove and install. All servicing in the field was to be handled by Andial staff. In this instance, Neil did dyno engine number 253 so it stands to reason that he also rebuilt it but I don't have those records to verify...

When it was last dyno'ed, the motor made 766 corrected horsepower at 8,000 rpm at 1.4 bar of boost. This was on Unocal 92 octane pump gas! Why? Because in Group C and in Japan, they had to run pump grade gas in the cars and 92 octane was the closest that we had...imagine the power potential left on the table!

Neil will dyno this motor with race gas and thus the motor could conceivably make more power, but since it is used for "gentlemen" racing at this point a safety margin will be built in for longevity purposes. The motors actually don't like alot of timing, the combustion chamber is very small and VERY efficient. The motor would make more power with better responsiveness using a modern EFI set-up and upgrading to modern turbos wouldn't hurt either as turbo technology has increased exponentially as the years have passed, probably second only to tire technology.

But, the owner wants to keep the motor original (both for cost and originality purposes) and I can't say I particularly blame him...

Ralph

[VZ935]

Originally posted by Carrera3.5L
I have tons of regular photographs that I took during the time period, but unfortunately this was long before the digital camera age....

It is amazing to me how much people are into the 962 long after its demise, and astounding that many of you have never seen or heard them in action but just have read about them in books or on the internet. I guess I really didn't appreciate it back than...but the car actually wasn't that good relative to the competition (it was TERRIBLE under braking) and wasn't well suited to the slower, tighter US tracks where downforce is important. The motor also left alot of power on the table due to politics inside and outside of Porsche, but those are stories that won't be told on a public forum, I don't want to burst people's bubbles about what really went on...

Ralph..very cool thanks for continuing on with the thread... would love to know if you have any pics of my 962... also, as far as competition... my car still holds the record for Average MPH and Distance Covered at the Sebring 12 Hour to this day , 20 years later .I believe some of the faster competition you mentioned ran that same configuration at Sebring too ..... Oh , it crossed the finish line on three wheels But you are right.. there were some brutally fast cars to come ....