The 'Prodified' 3.2SS

[911MANN]

First, a formal introduction: I am a frequent visitor and occasional poster but never contributed much to these forums. Now I hope I have something worthwhile to share. I've only found one digital photo worthy of posting here; all my other photos are paper pics from decades ago. I bought my 1983 Ruby Red Metallic 911SC in the Summer of 1988 after long desiring to own a 911. I'll post updated photos as the project continues. Very shortly after my purchase I was pleased to learn from my mechanic I had bought a ROW version, which he regarded as highly desirable.

Over the years he helped make my car more reliable and fun, with the addition of larger torsion bars, through-body sway bars, updated Carrera chain tensioners and SSI exhaust. All these were late 1980s recommendations from correspondence with Bruce Anderson (RIP)- all very good.

For many years I had wanted to do more performance upgrades, like 98mm pistons & cylinders and hotter cams, but the car ran so well I just couldn't justify it. Several decades later, as I approach retirement, I have put aside funds to pursue a nice project for my baby....But, what, exactly?

Now comes the many thanks to the Pelican Community, who have so freely shared ideas, information, successes and failures. I really appreciate that, and I hope to contribute a little here by sharing things learned during this project. Special thanks go to Steve Weiner, William Knight, Todd Uhl and Karl Schoepflin, Jr (my local air-cooled Porsche Specialist and Engine Builder). With their recommendations and guidance, I was able to develop project goals and particulars that give me confidence I will meet my needs and expectations.

I investigated many potential paths after reading about the different 3.2SS projects posted here over the years. I strongly considered PMO carburetors for all the performance recipes they allow, but I don't always drive it consistently enough to avoid the likelihood of clogging them. And the fuel odors in and around the car weren't appealing to me. My car is in very good condition, and I realized I wanted to keep more of a Gentleman's 911 than carbs might provide. I then went down the path of considering ITBs and EFI, a more modern approach than carbs, but the snag there was not having an air-cooled EFI guru nearby to diagnose/repair what would have been a nice but quite custom EFI system, and that lost much of its appeal. Then it hit me: Since each of these systems is a compromise in its own way, I needed to find and meet my top priorities. Two things emerged above all others: First, keep my Air Conditioning. I had just replaced and upgraded my old AC system and compressor with Griffith's parts only 2 years ago, so that was accomplished. Second, I need intakes that maintain the ability to drive in the heavy rains we get in Central Florida. Properly filtering intake air while keeping out heavy rain isn't always easy to find with the ITB options for sale, but they are available. And when I considered a third priority (long-term reliability), I came full circle in considering keeping the factory's CIS. I couldn't recall that system failing me in any meaningful way in all these years, and it easily met the other top priorities. I already had the ROW engine type 930/10, which was considered to be the best performing CIS variant. And Karl of German Car Service (my mechanic) was a CIS expert. Decision Made-- We would build a better-performing version of the factory's effort!

Now, Karl's daddy (Karl Sr, now sadly deceased) was born in Freiburg (Black Forest) and trained by the Porsche Factory many years ago. And Karl Jr had worked in his shop since a teenager (50ish years now), and as such has seen a great deal in his lifetime. When I shared the details of the project and my excitement for it, Karl insisted these improvements were NOTHING the factory hadn't already done some 40 years ago! These would not result in a 'Modified' engine, they only served to make a series of minor improvements to the factory's 'Production' car. He looked me in the eye and told me I wasn't talking about 'modifying' the engine; In his shop he calls it "Prodifying", and scoffed just a bit. Hence, the title of this project and thread....

Currently, the engine is apart, waiting in line for its components to be refreshed in several specialist shops around the country. I reckon late Spring 2023 will be the earliest she gets back together. I will be sure to post project specifics in a future post. Hint: William Knight's Melissa M1 Street Cams are in the recipe. Thanks for following.

[911MANN]

Well, I did post a nice photo along with the initial thread posting, but it hasn't appeared yet. The photo was placed in the rectangular box marked photo attachments, which noted that Pelican staff would re-size the image if necessary. Perhaps they will review/re-size/add it to the post after the Holidays.

I have always liked my revvy 3.0 engine, and I wanted to maintain that engine character with a few improvements. Major focus of this project: Increase displacement to 3.2L; Install William Knight's Melissa M1 Street Cams; Keep my ROW CIS; Various associated things to achieve a good result. I am also making some rather expensive improvements that aren't strictly necessary for a sporty 3.2SS, but I am doing them to increase robustness and to allow future flexibility in the event EFI and hotter cams are ever added. Below are the project particulars.

Bottom End (fitting and assembly by JB Racing)
Case and crankshaft oiling improvements
GT3 oil pump
Carrillo connecting rods with Carr bolts
Automobile Associates Clevite rod bearings
Updated 993 steel intermediate shaft and gear

Top End
Mahle 98mm pistons & cylinders with wedge-domes
Cylinder heads refreshed with flow improvements (but no porting) by Xtreme
Supertec cylinder head studs

Exhaust
Up-sized 41mm SSI heat exchangers
Dansk sport muffler 2-in/1-out with 84mm tailpipe

Associated Work
Refreshed fuel distributor & warmup regulator, adjusted for 3.2L by CIS Flowtech
Refinished engine tins and other parts with Cerakote by Tru-6
Refreshed 915/62 transaxle by California Motor Sports

I think that does it for the important stuff. Will try to take photos when things start coming together or if anything newsworthy develops.

[Uwon]

Following……
Johan

[Joesmallwood]

Following.... Love the idea of this engine strategy.

[nospiners]

I’m in on this too !! Keep goin , we r watching and waiting!!

[AcidGypsy]

Looking forward to following this one!

[icarp]

go to 3:24 to hear a comment about a free revving cis engine

https://www.youtube.com/watch?v=yrHp3_HuNbU&t=441s

Ian

[Brookieslayer]

Thanks for starting the thread and sharing.
Do you know what the duration and lifts (intake and exhaust) are of the Melissa M1 camshaft?

[911MANN]

Brookie- I believe William Knight said those cams are similar to the Webcam 20/21 in ramp angles and lift, with a modified duration. All that information is proprietary, I'm afraid. But William said he thinks it's the 'most' you can do with CIS, which must raise the bar just a bit when compared to the other popular CIS cam choices.

[Brookieslayer]

Originally Posted by 911MANN

Brookie- I believe William Knight said those cams are similar to the Webcam 20/21 in ramp angles and lift, with a modified duration. All that information is proprietary, I'm afraid. But William said he thinks it's the 'most' you can do with CIS, which must raise the bar just a bit when compared to the other popular CIS cam choices.

Thanks for the info!
I will touch base with Mr. Knight!

[PeteKz]

I am running M1's in my SC 3.2 long-stroke engine with Mahle Sport p/c's. When setting up the cam timing, I measured the clearances between the valves and pistons at several points in the crank rotation. They are very close, as close as .050" around the checking point. So it appears that there is no more lift or duration available than what the M1 cams provide. If you use the M1's and the Mahle Sport pistons, be aware of this and do not retard or advice the cams without careful checking valve-piston clearances before and after the checking point.

[911MANN]

Thanks to those expressing an interest in my thread! I didn't know how much interest it would generate, as my project is certainly not as ambitious or sexy as many of the other projects we follow in these forums. But I hope it helps others who might share my priorities or considering a similar project. I am keeping a spreadsheet of part numbers, sources and costs if anyone is interested- just PM me.

My car was manufactured during my University years, and that era resonates with me as the time I became fixated on these 911s and 911 Turbos. These cars were quite impressive at the time, and I want to respect everything I feel Porsche did right with them. Accordingly, my project will stay close to the car's original appeal and character, making a series of small improvements, the sum of which will hopefully yield a nice overall result. I have always thought of my SC as light, tight and revvy, and I hope to extend that revvy nature with the improvements I noted in the earlier posts.

I am trying to add some photos in this post (I know you guys love seeing pics). The only pieces I have at hand now are the intake runners and engine cooling fan. The intake runners were somewhat corroded in some areas but were surprisingly shiny in others. I soaked them in the recommended dilution of Simple Green Extreme, scrubbed them inside with a pipe brush and outside with a stiff bristle brush with good success. After excessive polishing effort with Flitz and Wenol, I switched to Mothers Mag & Aluminum Polish for a satisfactory result- took about an hour per runner. No telling how long they will stay looking like this, but this original stippled look is what I want (unpainted).

Now, the fan. After soaking it similarly, it cleaned up to reveal splotches of varying corrosion everywhere, including the inside. I recall from 8th Grade Science class how reactive Magnesium is, and my teacher was right! I carefully sanded with 220 grit sandpaper all areas to obtain a much-improved but far from perfect result. I wanted to keep the Mg look (unpainted) and considered having it Cerakoted in clear, but it didn't seem a good use of funds, with its visual condition. A new fan is about $380, and that I would probably Cerakote in clear if/when I were to buy one in future. For present purposes, I decided to brush-apply 3 thin coats of KBS Diamond Clear, a tough urethane coating that I hope will suit my purposes. The results are OK, I suppose, as the main things for me are to maintain a near-original Mg appearance and to immediately stop the corrosion.

The exterior surfaces of my cam chain housings were quite corroded. After trying for several hours to prepare just one of them, I decided to send them off to a vapor blasting service. I plan to coat them with the same KBS Diamond Clear when they come back, to prevent future corrosion. This product claims to be good up to 300*F. Even though the cam chain housings are in close proximity to my SSI exhaust, I am thinking that coating will be appropriate for that condition. Does anybody disagree?

Also, my fuel distributor and WUR came back from CIS Flowtech. Turnaround time was about 6 weeks, even with the holidays. All for now.

[toddu]

Looking good!!! Will be following along and anxious to hear about the first drive. Definitely the biggest case of “while you’re in there” for me (fan/housing, engine shroud, harness, fuel lines, etc.). Just need to draw a line at some point :-).

You’ll love it! (car looks great btw!!)

[ninesixfour]

Update?

[911MANN]

Well, Mr. ninesixfour, I'm so glad you asked! I was sure all the other followers had fallen asleep in the last six months! Things have been moving behind the scenes, and I was hesitant to post again until I had some meaningful contributions to offer. But since you asked, I'll start by listing timeframes for the specialty and other machine work performed over the last seven (7) months. Brace yourselves for some of these durations.....
Warmup Regulator and Fuel Distributor by CIS Flowtech in Fairhope, AL: 6 Weeks
Bottom End Work by JB Racing in Tavares, FL: 5.5 Months
Cylinder Head Work by Xtreme Cylinder Heads in Palm City, FL: 6.5 Months
*Xtreme was in process of revamping their operation, which extended my duration
915 Gearbox Rebuilding by California Motorsports in Lake Havasu City, AZ: 4 Months
Vapor Honing Chain Housings by Superior Blasting in Vale, NC: 2 Weeks
*Ryan Heavner; superiorblastingco@gmail.com; 828-244-8392
Engine Tins and associated engine bits by Tru6 in Watertown, MA- 8 Months
Rocker Arms Resurfacing by Dougherty Racing Camshafts in Shingle Springs, CA: 2 Months

I am sharing these durations so that folks get a realistic idea of just how long these projects can take- certainly not meant for the instant gratification crowd. My engine assembly has just started at German Car Service in Longwood, FL. We are expecting the cylinder cooling tins (along with the other CeraKoted parts) to be delivered next week, which will allow things to move forward.

I posted a few photos to maintain interest. Yep, that's me in the engine compartment! I did a respectable cleaning, but nothing worthy of pics. That Simple Green Extreme really is the cat's ass for cleaning aluminum. My filthy old swing arms cleaned up to a bright appearance with minimal scrubbing. I installed Dansk stainless steel heater valve boxes for only a few bucks more than the OEM painted steel versions. My car has been garaged for my 38 years of ownership, yet those original heater valves looked to have been buried in a swamp for the whole time! New black engine sound pad, engine enclosure seals, decklid shocks and a few other bits were about it.

Next photo is my original valve covers, tumbled and CeraKoted Clear by Shaun at Tru6. He sent this photo in advance of shipping, and I think they look great. The color theme of my engine is very much original as Porsche produced it when new. Either freshly cleaned metal or clear-coated aluminum where likely to corrode. Nothing is painted except as Porsche did it 40 years ago, only this time done in black CeraKote for better longevity.

Last photo is one of my cam chain housings and cover after vapor honing and brush-applying KBS Diamond Clear similarly to my engine cooling fan and housing. Spraying that product might be a better option for some, but I felt more confident brushing. Man, those things were severely corroded when disassembled. Now they look like new and are protected from future corrosion.

I will try to post developments as assembly continues in August, and I will try to post interesting tidbits as well.

Thanks for your interest. This project is intended to be quite close to a Full Monty with CIS, which is perhaps different from the many more ambitious projects documented in these forums. But this approach felt right to me, and it felt true to my vision of the next chapter for my Old Baby. Damn, I love this car. And I do have high hopes this result will be impressive. You guys don't know I bought a 2011 GT3 back in 2018 to replace this 911SC, as a nod to my acceptance of aging and moving on to another chapter in my life. But I simply could not bring myself to part with her. Now I have both cars, yet the old one has been the one who calls me to drive her most frequently. I am dying to see how she goes in this new incarnation. Stay tuned.

[911MANN]

I'll give it another go with the pics- sorry.

[ninesixfour]

Thanks for the update. Those wait times are quite long, not for the faint of patience.

[911MANN]

Engine assembly continues and is picking up pace now. The attached photos are nothing new for this forum, but here they are.

I expect my real contributions here will be to share some details of my project with those who are considering pursuing my same path of marrying the 98mm Mahle piston and cylinder kit with William Knight's Melissa M1 cams. Somebody else must have done this, but in all my research, I could not find anyone's comments on this combination. It seemed to approach a more-or-less Full Monty 3.2SS while keeping CIS. Some true experts would likely be able to take things further with improved ignition, etc., but this is the outer limits of the scope of my original vision. I fancy my project as one that a Top Porsche Executive might have had commissioned for his personal car back in the early 1980's: A 911SC Plus-Plus, something fully recognizable as a factory effort with some juicy improvements.

I had understood from others using the Melissa M1 cams that piston-to-valve clearance would be tight. My cylinder heads had been resurfaced for the first time along with the flow improvements, and we were watching that clearance closely. Using 0.5mm cylinder base gaskets yielded a 1.13mm deck height; so far, so good. Even though he prefers the degree wheel method for best accuracy, William Knight had given me an ideal cam timing target measurement for the #1 intake valve lift measured via the Porsche method, and the trick is to ensure the corresponding #4 exhaust valve still maintains proper clearance at that same spot in the cycle. I had been hoping the shallow valve reliefs in the Max Moritz style wedge-dome pistons would offer a bit of safety, and I think they provided that, as we achieved an exhaust valve clearance of right about 2mm- plenty of safety. We were happy with that result, and that should give confidence to others using this engine formula.

I won't make any predictions as to the completion date, but it shouldn't be long now. Thanks for your continued interest.

[911MANN]

Photo 1: 98mm Mahle cylinder showing very slight chamfer mating to cylinder head.
Photo 2: Cylinder head following flow improvements by Xtreme.
Photo 3: Mahle Max Moritz style piston with wedge-dome shape for CIS.
Photo 4: Bottom end assembled.
Photo 5: Assembly progress.
Photo 6: Assembly progress with engine cooling fan mounted.

The hand-sanded and clear-coated result of my original magnesium engine cooling fan doesn't look quite as nice as the rest of the engine- it's just not very uniform. The feeling of doing it myself and saving a few bucks was good, but I'm not sure it's on the standard of the rest of the engine.

[ninesixfour]

Coming along nicely. Sorry it’s been a long time since I rebuilt my SC engine but what do you gain by having such tight tolerances with the cams? The highest possible compression ratio? What is the goal output?