68L engine rebuild at PCM

[mrar]

Are you driving around the city or plenty of hwy driving?
If it's the city the s spec stuff would be wasted imo as cams don't really kick til 5+k rpm plus cooling could be a issue in hot day traffic as the swb models inc s didn't have a external front mount cooler.

[Merv]

Looking good Mario. When I fully rebuilt my 2.0L almost 2 years ago, I went through the same process. There are always aspects that are not expected. I dickered around with piston/barrel choices as well (including the well-priced Birals from AA at the time) and eventually went with the many commendations in the US for the (stock sized) LN Eng Nickies barrels and JE pistons. They were around $AU7000 at the time. DHM did the case, cams profiles, heads, bearings, crank profile check, added IMS bearing, new rods, valves/guides, new SC oil pump, parts balancing, etc, etc. I also kept the Carrera tensioners.

The 2.0L is never a torque monster, but it was stock on this matching numbers car. Now it is such a sweet revving motor and I am glad that I kept it stock. The mag cases need careful management however.

https://www.typ901.org/forum/forum/typ901-register-forums/general-technical-info/5439-engine-re-furb/page3

[mario lanza]

Thanks Merv.

At least with Alloy case i don't have those issues - just some ancillary engine covers and gearbox bits in Magnesium.

Did you run S valves and porting and what cam in your L?

Thanks Mrar also for scaring me about the cooling! Yes its on our mind but Peter at PCM feels that with those S heads the motor won't run well with a lower spec cam.

I assume as a US spec L with emissions/cast barrels/normal (pre E but similar) cam it would have run a little hot. Hopefully with alloy barrels it will be fine on s spec cam.

Any other guidance would be appreciated.

[Merv]

Mine is a 130HP US Normal (not T) motor Mario. The stock cams were very slightly worn so the engineer re-profiled (and re-hardened of course) them a tad more aggressively. Cams and crank were tested for cracks and balanced. The P/C set also increased the compression ratio a bit above the stock level, and I re-jetted the carbs (always worth considering as jets tend to 'evolve') and the car was tuned accordingly. I found a near new SC oil pump and this gives outstanding oil pressure now (after the by-pass necessary modification) and car runs much cooler than previously (around 180*F). Also replaced the relief valve.

[epilot]

Mario, I run the LN Engineering Nickies and custom JE pistons in my race car, they are beautifully engineered and made.

[CamBiscuit]

I'd go with the Nickies - pretty sure they have more cooling fins from memory? Also maybe consider a Mod Solex cam - they are roughly between an E and S profile.

[Fishcop]

As a fellow 68L owner you'll get my 2c as well...

Things to consider... these engines are raced regularly here in Australia and overseas in FIA historics, none run external cooling. Alex Webster and Tom Walstab on the forum both have run 2.0 engines at the front end of competition and their cars cannot be externally cooled. I don't think you need to factor in overheating a 2.0 in southern Australian climates No disrespect to your builder, but there are independent guys who build these engines as bread and butter (as in don't touch later Porsche engines) and I'd suggest heat transfer (particularly in an alloy case) is not a major issue for their 2.0 engines.

Are you keeping the car "for ever"? Even if you are, these engines will out live the ownership of most of us given the likely miles they will travel now - go with rebore and wossner pistons and keep your costs down.

Are you racing the car (which is my intention)? Maybe then consider the NIckies. I personally will be running factory birals and custom JE pistons.

Definitely do the oil pressure mods and improve your oil pump (use a SC unit if you can find one)

Regarding build spec - it's 2.0 litres... You'll never get a stump puller no matter how it's built. I'm going to run hi-compression pistons and a custom profiled camshaft (something close to ModS). The reasons for the custom camshaft is to capitalise on modern fuels in conjunction with improved ignition available to us in this era will offer a little more torque. Gearing your box will make even more difference to driveability than engine work. You should have the AFMSX cluster. If you're going for a road oriented car, look to chasing a Z 5th gear (AFMSZ) which will give you a taller final drive for better touring.

Regarding originality - so long as it externally looks as delivered, no one will take umbrage at improved internals

[Merv]

Mario, John's point about gearing is also on the money, especially if you want a higher 5th for touring. Also start the search now for a good SC pump. A 964 pump can also fit but I believe the case needs some machining to take it. A decent builder should be able to source one, if needed. These Birals (https://aapistons.com/collections/po...e-cylinder-set) were my second choice. I got the 80mm 9.5 comp P &C's) and would still buy the LN Nickie/Custom JE's again due to their advanced design and extra cooling.

[mario lanza]

Thanks Merv, let me know if you have a spare SC pump for sale! It appears that a Carrera pump is the practical solution and it has been suggested there is a suitable sump plug with drainer. Do you regard the IMS bearing as essential?

Thanks E-pilot have you got nickies on a road car - i am curious as how they cope with traffic rather than Group N or S sprints! It is only relevant to my next build as I had ordered the mahle stuff.

Yes Cam they say more fins per inch in the LN material! There must be a trade off in the no. of fins and the distance between them though and heat dissipated. It been a while since i studied thermodynamics! I hope mahle motorsport have chosen not to adjust that parameter for sensible reasons other than r&d cost?

Then again, perhaps the consensus is the nickies are a better product- not just a well engineered product- but better. I will try them on my 2.2 T next year...

Thanks Fishcop - i hope to keep the car - i really like the clean lines of the SWB. I have a mini race car and i dont have guts to hammer a swb on the track. I assume a carrera oil pump will be as good as an SC save for the sump plate issue? I am considering the mod s cam and looking for feedback on that choice given the pistons / barrels / head choice. Longer distances (e.g. interstate) are done 4 up in the carrera 2.7 so i hope this car is club runs and melbourne stuff. What are your thoughts on gearing given this? I dont want tall gearing i assume (??) but am open to your advice (and Merv's) on this? Is 3200 rpm at 100kph in 4th about right maybe 2800 in 5th reasonable?

[Merv]

Yes Mario, the SC Carrera pump is the one. Not that many lying around in Australia just now and even though Tom Butler in the US would have some, the freight is the thing. I did see this on GumTree this morning, but not sure if it is still there.

https://www.gumtree.com.au/s-ad/hornsby/engine-engine-parts-transmission/genuine-used-porsche-911-sc-carrera-3-2-oil-pump/1130382937

My Nickies are just fine in traffic. Cool compared to my original stock P/Cs.

The 68 motor didn't, I was told by DMH, have an IMS bearing but Phil Summich the respected engineer doing the case, strongly suggested fitting one. I did what he advised in all things ..

The RPM/speed characteristics you describe seem fine to me. Most of my driving is at 100-110kms/hr here with few city streets and very few traffic lights and my gear box is standard. GPS calibrate your speedo also so you know what you are really doing out there.

[mario lanza]

Pistons, barrels, valves and fuel pump have arrived.

Fuel pump was the bendix labelled diaphram type and this seems to have been common on the 7/67 build cars. As we know they were a pierburg build with the "in" and "out" written in german on the side. Last NOS one on ESR sold privately near $800 U.S.

Anyway, Hardt Classics here on the Melbourne peninsula are assembling a quality replica for 356 boys and sending them all over the world. Unlike the Facet rebranded pumps (or the cheaper asian copies) Hardt say they put in the body a genuine diaphram pump mechanism. They say their pumps can be set by them to exactly the desired PSI you need for your induction and also ensure the flow (as opposed to pressure) is adequate for the engine. Peter Bowen provided a pressure and flow rate. On our Weber 40 IDA we requested .28-.33 bar(float needle closed) and 900cc min flow.

As shown in the photos Hardt also provide a full set up if desired - fitting, bushes and german fuel hoses. Fantastic value for $210 delivered. Call them or see their stuff on ebay.

[Merv]

They look much like mine Mario. I have had no problems. The Facet-derived pumps are fine and with the right decal and (e.g.,) Enzed fittings they can look very original. I made up a bracket very similar to the one that you show there. The range of Facet pumps includes one that is 3-5psi (0.3-0.34), as I recall. How did you go with the oil pump?

[PCM911T]

Engine Done??

[ELSPORTO]

Yeah dying for an update on this Mario!

[mario lanza]

Sorry for the delay! Peter Bowen has removed the MSD and got the engine bay ready....

Mahle motorsport stuff has arrived from Parts Wise - well packaged.

Alloy barrels are very light in weight.

Mahle s pistons in alloy look to have a heat treating on the inside of the pistons (low sheen finish).

Rings are fitted and look very good quality but i assume they will be removed/gapped and put in again....

From recollection delivered cost was about $4,500AUD plus tax.of about $1k. Same pistons out of U.S. were about $2k more.