Going from planning to executing issues, my 3.0sc hotrod build.

[Rivet]

Making final preparations on my motor and only now am I considering a set of Wossner rods after rebuilding and balancing the stock set with ARP bolts.

What's another few bucks in the grand scheme of things?


Anyone want to buy a set of rebuilt 3.0 rods ?

[PeteKz]

What RPM do you plan to redline? If under 8000, keep the stock rods.

[Rivet]

Thank you Pete, my gut was comfortable with 7.5k as a ceiling with safety margin built in, the extra 500-700 rpm was making me uneasy.

In the race motorcycle motors I build for customers this type of build almost always gets a set of rods just for safety sake. We can invest a ton of time and money on a set of engine cases and putting a hole in one can be a huge setback in time and money to prepare another set (not unlike building a Porsche motor)

The cams are DC60 and I am expecting it to make power to the mid 7k rpm area so 8-8.2k rpm would be about the ceiling accounting for RPM drop per gear change.

[PeteKz]

If it makes you more confident, then go for it. I have found over the last 30 years that it's hard to improve on the original Porsche components. What do the Wossner rods weigh, compared to the stock rods? If they are lighter, how did they remove material without making them weaker? It's possible to do, but as I said, it's hard to improve on the OE design. Are the rod bolts larger? If not, how are they improved over the ARP bolts you already have?


Not trying to be a PITA or naysayer, just asking to make sure you really will get what you think you will pay for.

[Rivet]

Originally Posted by PeteKz

If it makes you more confident, then go for it. I have found over the last 30 years that it's hard to improve on the original Porsche components. What do the Wossner rods weigh, compared to the stock rods? If they are lighter, how did they remove material without making them weaker? It's possible to do, but as I said, it's hard to improve on the OE design. Are the rod bolts larger? If not, how are they improved over the ARP bolts you already have?


Not trying to be a PITA or naysayer, just asking to make sure you really will get what you think you will pay for.

Pete,

They are very similar in weight to the Carrillos at 558 grams vs the 691 grams the current stock rods are with the ARP hardware installed. They are also an H beam rod same as Carrillo, but they are manufactured in Germany.

It is a much stronger rod than stock, and they are provided with ARP hardware with similar rated tensile strength to the stock replacement ARP bolts and more importantly they have a much more rigid end cap to better provide a dimensionally stable big end dimension at sustained high rpm.

[Rivet]

I just started the last inspection part of the project. I am stealing time here and there between customer work.

I build and calibrate (tune) 14k rpm racing motorcycle engines for a living and am tooled for such so when presented with splitting the cases on my motor I had to hastily whittle up a tool to help in that regard. I took "inspiration" from Stomski which makes amazing tools as we all know and took scrap cut off aluminum and a snap on puller tool and hastily threw it up on the Bridgeport.

And success. first visual inspection shows all bearings except for IMS and bearing set nearest the flywheel show no wear. After some cleaning I will break out the measuring tools and measure for current main bearing clearances.

If anyone has any interest in purchasing my refurbished rods and sustain my insanity I listed them up on the marketplace, https://forums.pelicanparts.com/porsche-911-used-parts-sale-wanted/1151387-fs-911-3-0-sc-rebuilt-connecting-rods-arp-bolts-balanced.html

[Neil Harvey]

Be sure you understand why you need these new rods. Nothing will give more driving pleasure than a light car and lightweight engine internals.

There is a difference between top speed and acceleration. I would take acceleration over top speed. But that's my choice.

Aftermarket rods are typically sold dimensionally, not by application or use. They are usually dimensionally the same as stock, therefore their application is to suit a particular engine model. The same rod is sold for an NA or Turbo engine in some cases.

An 3.0L NA engine or even a 3.6L NA engine will never have an issue with a stock rod. The rod will never see compression numbers to hurt it. Same for the bolts.

But if there is a better part available, for sure use it. But understand why you are using them.

For a NA engine, the typical H beam is overkill. An I beam will work and be lighter. To give a comparison, we build NA engines with displacements over 4.0L with Steel Rods that have a longer CCL and weigh 420 grams without the bolts. We use Titanium bolts in some and steel in others.

Our design parameter is to have parts designed for each application and lightweight that allow the engine to rev quicker.

Budget dictates what is possible too. There is absolutely nothing wrong with your choice or other alternatives sold in the aftermarket. 560g is better than 690g, for sure but understand why you are changing.

Your post states you build motorcycle engines. I assume you are looking for acceleration as well as a higher RPM. Motorcycle internals are a lot smaller and lighter in comparison to car parts. Porsche 3.0L engine parts are some of the heaviest car parts as Porsche built these engine with overkill in mind. There are more important concerns with these engines using high RPM than the stock rods.

If all you are trying to achieve is a higher engine RPM, save your money and use what you have.

[Rivet]

Originally Posted by Neil Harvey

Be sure you understand why you need these new rods. Nothing will give more driving pleasure than a light car and lightweight engine internals.

There is a difference between top speed and acceleration. I would take acceleration over top speed. But that's my choice.

Aftermarket rods are typically sold dimensionally, not by application or use. They are usually dimensionally the same as stock, therefore their application is to suit a particular engine model. The same rod is sold for an NA or Turbo engine in some cases.

An 3.0L NA engine or even a 3.6L NA engine will never have an issue with a stock rod. The rod will never see compression numbers to hurt it. Same for the bolts.

But if there is a better part available, for sure use it. But understand why you are using them.

For a NA engine, the typical H beam is overkill. An I beam will work and be lighter. To give a comparison, we build NA engines with displacements over 4.0L with Steel Rods that have a longer CCL and weigh 420 grams without the bolts. We use Titanium bolts in some and steel in others.

Our design parameter is to have parts designed for each application and lightweight that allow the engine to rev quicker.

Budget dictates what is possible too. There is absolutely nothing wrong with your choice or other alternatives sold in the aftermarket. 560g is better than 690g, for sure but understand why you are changing.

Your post states you build motorcycle engines. I assume you are looking for acceleration as well as a higher RPM. Motorcycle internals are a lot smaller and lighter in comparison to car parts. Porsche 3.0L engine parts are some of the heaviest car parts as Porsche built these engine with overkill in mind. There are more important concerns with these engines using high RPM than the stock rods.

If all you are trying to achieve is a higher engine RPM, save your money and use what you have.

Well put, and knowledgeable post Niel. I know you are well versed in engine building.

I agree on all fronts, and your points have been mulled over for a bit now hence the inner turmoil in my brain.

In the essence of sharing engine building information in public forum I'll just add some points for fun for the group as a whole. I am always on the path to motorsports enlightenment whether it be engine building, chassis design and my favorite, engine calibration. I celebrate the sharing of information with people on that same path.

Cylinder pressure is almost never a cause of failure to a rod, within reason. It is almost always an oiling/oil cushion failure that will cause issues for the rod and subsequently the engine cases sometime . With the exception of gross calibration issues or fueling errors we never see a cylinder pressure rod failure in max effort motorcycle engines (ie. base timing errors/timing drift, extreme detonation at high boost or high nitrous loads from exuberant tuning and occasional hydra locking of methanol when the ignition system fails to fire with very rich lambdas at high boost and rpm). It never ceases to amazing me the abuse these 400-800hp, 1-1.7 liter four cylinder motors take when I am tuning them on the dyno or the track.

Keeping the rod dimensions as stabile or rigid as possible is the ultimate benefit of a properly engineered aftermarket rod option (also engine case rigidity in the main bearing areas), allowing the engine builder to size bearing clearances to suit their ethos in building, the overall design of the motor and its intended usage.

Overbuilding as a whole is a nice insurance policy sometimes, especially in a race motor.

[PeteKz]

Rivet, if you have built a lot of race motors, you know all about the slippery slope, etc. Your money, have fun!

[Rivet]

Originally Posted by PeteKz

Rivet, if you have built a lot of race motors, you know all about the slippery slope, etc. Your money, have fun!

All I can say is that this obviously edited screen shot of a social media post says it best!

I am still learning in all aspects, what I will probably never learn though is fiscal responsibility

[Rivet]

As un update I am currently awaiting some new rods to show up while cleaning a glorious amount of Loctite 574 off the cases. The last person to have this motor apart was a little too ambitious in the search for an oil tight motor.

On the race engine front in general, I am not a sharer and my comfort level on forums is mostly of the lurking kind. Some of the stuff I am involved in is the non sharing type but I decided to share a little non 911 stuff because there is a possibility of fellow hotrodders thinking it is interesting and I am waiting for chemicals to do their job to help in 574 removal.

Please let me know if adding non 911 motor stuff is frowned upon and I will remove this post.

I have been very fortunate enough to be involved in some pretty awesome race programs in NHRA PSM, AHRMA road racing, AMA flat track, XDA, etc. The first of three I'll share is one we are very actively getting together to improve on our old setup and am very excited about. I am the race calibration specialist and engineering consultant for the world's fastest drag racing nitrous motorcycle. It is based on a late 70's, early 80's Suzuki GS1000/1100 but obviously a little removed from stock. The best ET so far has been 6.403 at 221.78 mph for the quarter mile and 4.182 at 179.49 in the 1/8 mile.





The motor currently is an all new prototype that is based on Vance and Hines racing's current NHRA Pro Stock motorcycle engine. It is a beautiful all billet power plant that is a test bed for Vance and Hines to offer a Pro Mod version of the motor which is very similar to the class that we run in, Pro mods and our motor use nitrous oxide in huge amounts (north of 1200 lbs per hour).

The real benefit to us is in this newest combination is the engine case rigidity over using modified stock cases, along with now offering a cassette transmission that will allow trans servicing and repair without disassembling the entire motor between rounds. As we are still in development of our entire package to suite this new motor I don't have any media showing it in use or installed.

But I can share a video of the first generation Vance and Hines pro mod billet top end mounted to stock Suzuki GS cases on my chassis dyno from the beginning of last year. The video shows some initial ring seating process and some rough calibration adjustments to account for the new top end. Since this motor uses more nitrous oxide than atmospheric air it takes a different approach to tune than normally aspirated or even forced induction.

[Rivet]

The next one is a compound turbo Hayabusa for land speed racing usage.

This one is using a smaller turbo housing to feed a larger turbo that is front mounted.

This video shows some testing being done on my dyno checking for EMAP to MAP ratios to map out better efficiency.

This thing is a work of fabrication art. It is being developed for a 300 mph in the standing mile attempt which is an incredible goal.



The last one I will bore you with is a normally aspirated drag bike that is run in a heads up class along with turbo charged and nitrous injected packages. There are some rules that attempt parity given such different combinations racing together and one of them allows non spec fuels for NA motors.

For this one I blend my own fuel that is Methanol based. It displaces approximately 1700cc with four cylinders and makes 300 hp at 12k rpm. This thing is an absolute monster, its best time in full street trim (heavy) is 7.40 at 184 mph and currently holds the record for MPH among the normally aspirated bikes in the class.

[Rivet]

Always a good time when I can use my Stomski degree "wheel". I originally bought it to replace my 18" diam degree wheel I used to use on motorcycles and has been an extremely worth while tool to invest in. And every once and awhile it will end up on a Porsche motor





This motor will be using 45mm RHD individual throttle bodies matched to the 39mm early SC ports and will be managed by my preferred engine management system.

Before getting some r&d time on the Maxxecu system from Sweden a few years ago I specialized in Motec, Microtech and Haltech when not using stock ecus or carburetors and I have to say now I am spoiled. I pretty much exclusively utilize this awesome engine management system now.

Spark will be supplied by NGK "smart" coil on plug coils, and I will be using a Plex tuning or Motec dash data logger during the initial tuning time.






Pistons awaiting install are Wossner 10.5:1 into re plated cylinders.






All this will be used to push this Targa down the road.

[911 SLANT]

Nice build

[PeteKz]

That's a lot of eye-candy. Very curious how it turns out. I still run CIS on my RoW SC stroked to 3.2. From time to time I think about an EFI.

As for posting the pics and videos of the motorcycle motors, by all means, continue to share. You're among fellow addicts here.

And you have probably heard the Roger Penske statement that "racing is the sport that turns money into smoke and noise."

[mepstein]

Always happy to see and learn about what experts in other fields are doing.

[Rivet]

Thank you guys, I appreciate it.

PeteKz, Roger Penske might know a thing or two about turning money into smoke and noise.... Excellent!

[Rivet]

Just in case anyone is going to the Performance Racing Industry trade show this weekend in Indianapolis I will be at one of my suppliers and good friend's booth when I am not hobnobbing around. Booth number #111.

We will have our friend's NHRA Pro Stock Motorcycle on display. He is sponsored by a Taquila company and I am sure they will have some product hanging around.

They are also doing a giveway for another sponsors electric pit bike made by Burromax.

[Rivet]

Back at the shop after a great PRI.

I won't bore you guys with the motorcycle stuff but I did find some cool relevant motor updates.

Noonan racing engines offers a billet 911 case for $12.5k and after seeing it in person it is gorgeous. https://noonanrace.com/products/911-porsche-case

"After a successful season of on track testing with Renn-Link Racing, USA the engine case is now being released to the marketplace. The engine showed incredible durability and reliability throughout the season, with almost 60 hours on track time utilizing the same bearings, Team Crew Chief – Tim Carey said, “the engine has exceeded our expectations beyond belief. We have always had to replace bearings at 25-30 hours and generally scrap the engine case due to fatigue and cracking in the weak zones, the billet case has by far out performed this and we are excited to see how far we can really push it.”





And Greek based ZRP is working on a full line of products for aircooled Porsche applications that will be available in around a year from now. They are a leading manufacture of motorsports forged cranks, rods and pistons in Greece and they really do have a nice product. https://zrp-rods.com/

[Rivet]

Bringing this one back from the dead...

After an embarrassing amount of time I finally have this engine done, installed, broken in, tuned and with 1k miles on it.

I ended up with NOS R&R steel rods from a fellow Pelican from a project that changed direction. It is a shame that they no longer make them as these are some of the best I have seen, and I have seen a ton of connecting rods. Weight was lighter than Carrillo, weighed identical to each other and big end sizes where spot on.

The engine went together with out any drama. I used main bearing clearances that may seem out of place compared to what I have seen discussed and rod end bearing clearances that are near what I see discussed here. For the time being I will keep these numbers private but I do love seeing the oil pressures and temperature data I have collected over the summer.

Quench, or "squish" was set at .030", compression was just shy of advertised 10.5:1 from Wossner as expected. The pistons measured great and where identical in weight.

DC60 cams where degreed at middle spec and I used mechanical cam chain tensioners with racing chains. I have no issues with the added maintenance and slight noise during warm up.

I didn't document a tone but I will share some photos.

Rod differences.











Bare piston weight for Wossner's 95mm offering. I didn't take any photos of the pistons after some modifications, but have included some of the first mock ups.







Here you can see the cylinder 3 thermocouple wire and connector and the stock port heads.




Just a sprinkle of off topic... You have to love Open class Pinewood derby racing, I love that our troop has a limited rules parent's class. This one was good for a significant bump to the track record.