I am making reproduction Porsche engine cases!
08-06-2017, 09:30 PM
#31
Addict
08-07-2017, 02:00 AM
#33
Rennlist Member
Kudos to you, sir, for taking in such a big project. I am now following the progress of this with great interest. I just finished a four year build of an ST project and I will tell you that if your case was in production I would have strongly considered one as an option since there is really nothing original about my hot rod build. Talk about peace of mind; I spent a bunch improving the mag case for my car. Having a new, stronger, improved case would remove any remaining concerns.....
Good luck and keep,it going.
Good luck and keep,it going.
08-07-2017, 10:20 AM
#34
Rennlist Member
BTW, the strontium infused A356.0T6 is a common way to reduce (and perhaps shape) the grain size
a search in a materials science journal database will produce a lot of info; ASTME also
on a related note... a really well designed CAE crankshaft would be nice - modern methods could reduce wt. and increase strength even as compared with the later stock cranks which also used CAE
then there the cams - PAG started using hollow tubes with the Boxster/99 (IIRC) to save wt. - the lobes are pressed on
a search in a materials science journal database will produce a lot of info; ASTME also
on a related note... a really well designed CAE crankshaft would be nice - modern methods could reduce wt. and increase strength even as compared with the later stock cranks which also used CAE
then there the cams - PAG started using hollow tubes with the Boxster/99 (IIRC) to save wt. - the lobes are pressed on
I have never had the need to use additives for ultimate strength. We continuously achieved mechanical properties of 30k PSI+ yield 40kPSI+ tensile and >3% elongation from both separately cast bars and even greater results from sub-sized bars cut from the castings itself. Grain size was never an issue and if you have good foundry practices shouldn't need any additions.
I made engine cases and transmissions for G-force racing for years. These were used in the truck racing of the time and they stood up to some serious pounding. Most of my parts were used on helicopters like the blackhawk/seahawk, Super Stallion, Chinook, E2C hawkeye, B52, B-1, B-2 etc. My specialty was low production parts with complex features. A 1 pound aluminum casting with 300+ dimensions all needing to be held to +/- .030" tolerance.
It is nice to see another foundry last so many generations. Although I have to say their sand mix might be their weakness. There is no reason for the surface finish and the sand that broke free leaving clumps of metal in the openings or what appears to be a missrun.
If you find they give you a hard time. I have a foundry hear in Jersey (one of the last) that is fantastic. One of the best foundryman I know and his parts come out looking perfect with far better surface finish and can draw far deeper reliefs than your guys seem to be doing. He has a number of Sinto molding machines and has the best control over his sand mix. We also just worked on developing a new sand mix for magnesium that makes a stunning casting that would be hard to believe was made in sand. If you ever want to dabble in magnesium let me know.
08-07-2017, 12:39 PM
#35
Banned
Thread Starter
Kudos to you, sir, for taking in such a big project. I am now following the progress of this with great interest. I just finished a four year build of an ST project and I will tell you that if your case was in production I would have strongly considered one as an option since there is really nothing original about my hot rod build. Talk about peace of mind; I spent a bunch improving the mag case for my car. Having a new, stronger, improved case would remove any remaining concerns.....
Good luck and keep,it going.
Good luck and keep,it going.
When I built my 914-6 GT clone, and I couldn't get a 3.6, I decided to go with a mag case 2.7 mainly because nothing else sounds like one. Walt put over 5K in machining that case, and in the end, it was no stronger or better than it was when new, it was just more or less back to original.
To me, that was unacceptable, just as it was unacceptable to pay some guy 10K for a 3.6 motor that had a top end fire and melted the shroud and wiring.
We should have better choices than that!
08-07-2017, 12:47 PM
#36
Banned
Thread Starter
I have hand written R&D papers from my grandfather dating back to the 1930's when he was head of Bendix's Eclipse pioneer program nearly 3000 employees. They were producing some 2 million pounds of aluminum and 1 million pounds of magnesium castings in the day. I pulled some of his papers and he experimented with Strontium and Beryllium and many other additives and found little benefit over proper gating and risering. His R&D was released to the federal government during WWII reducing national scrap rates by over 40%. Sadly I see many papers released by others some 20 years later taking claim to his work.
I have never had the need to use additives for ultimate strength. We continuously achieved mechanical properties of 30k PSI+ yield 40kPSI+ tensile and >3% elongation from both separately cast bars and even greater results from sub-sized bars cut from the castings itself. Grain size was never an issue and if you have good foundry practices shouldn't need any additions.
I made engine cases and transmissions for G-force racing for years. These were used in the truck racing of the time and they stood up to some serious pounding. Most of my parts were used on helicopters like the blackhawk/seahawk, Super Stallion, Chinook, E2C hawkeye, B52, B-1, B-2 etc. My specialty was low production parts with complex features. A 1 pound aluminum casting with 300+ dimensions all needing to be held to +/- .030" tolerance.
It is nice to see another foundry last so many generations. Although I have to say their sand mix might be their weakness. There is no reason for the surface finish and the sand that broke free leaving clumps of metal in the openings or what appears to be a missrun.
If you find they give you a hard time. I have a foundry hear in Jersey (one of the last) that is fantastic. One of the best foundryman I know and his parts come out looking perfect with far better surface finish and can draw far deeper reliefs than your guys seem to be doing. He has a number of Sinto molding machines and has the best control over his sand mix. We also just worked on developing a new sand mix for magnesium that makes a stunning casting that would be hard to believe was made in sand. If you ever want to dabble in magnesium let me know.
I have never had the need to use additives for ultimate strength. We continuously achieved mechanical properties of 30k PSI+ yield 40kPSI+ tensile and >3% elongation from both separately cast bars and even greater results from sub-sized bars cut from the castings itself. Grain size was never an issue and if you have good foundry practices shouldn't need any additions.
I made engine cases and transmissions for G-force racing for years. These were used in the truck racing of the time and they stood up to some serious pounding. Most of my parts were used on helicopters like the blackhawk/seahawk, Super Stallion, Chinook, E2C hawkeye, B52, B-1, B-2 etc. My specialty was low production parts with complex features. A 1 pound aluminum casting with 300+ dimensions all needing to be held to +/- .030" tolerance.
It is nice to see another foundry last so many generations. Although I have to say their sand mix might be their weakness. There is no reason for the surface finish and the sand that broke free leaving clumps of metal in the openings or what appears to be a missrun.
If you find they give you a hard time. I have a foundry hear in Jersey (one of the last) that is fantastic. One of the best foundryman I know and his parts come out looking perfect with far better surface finish and can draw far deeper reliefs than your guys seem to be doing. He has a number of Sinto molding machines and has the best control over his sand mix. We also just worked on developing a new sand mix for magnesium that makes a stunning casting that would be hard to believe was made in sand. If you ever want to dabble in magnesium let me know.
It is very important to me that the entire project be run right here in California, where I am close to all the parties involved.
That said, the foundry was more concerned with getting the gating right, and they took almost 3 weeks fiddling with it. When they poured #1, the one you saw in pictures, they were within 95% of perfection.
I am not defending them, but they did a pretty good job considering the only people that have poured these cases are PORSCHE and ME. Lots of things learned there on our part.
I posted pics of the first raw casting not to showcase how perfect it was out of the mold (it was far from perfect) but to showcase how far we have come.
The foundry has never given me a hard time; they have been amazing partners and frankly have put so much human capital and brainpower into this project because they WANT it to succeed. They have way more profitable jobs and DOD contracts they can be pouring. The case is a pain in the *** for them, but they are eager to accept the challenge, and I have been working with them for over a year. They have bent over backwards to get to this point, and I am going to let them work through their mistakes and errors and ugly surface finish (which I pointed out in an earlier post) until they can achieve the excellence I know they are capable of.
Let's give them a chance to do better. We have all been working on this tirelessly for a year and a half, and we don't have Hans Mezger on hand to answer questions nor a slew of Porsche engineers with blank checkbooks.
08-07-2017, 03:25 PM
#39
Rennlist Member
Cobalt,
It is very important to me that the entire project be run right here in California, where I am close to all the parties involved.
That said, the foundry was more concerned with getting the gating right, and they took almost 3 weeks fiddling with it. When they poured #1, the one you saw in pictures, they were within 95% of perfection.
I am not defending them, but they did a pretty good job considering the only people that have poured these cases are PORSCHE and ME. Lots of things learned there on our part.
I posted pics of the first raw casting not to showcase how perfect it was out of the mold (it was far from perfect) but to showcase how far we have come.
The foundry has never given me a hard time; they have been amazing partners and frankly have put so much human capital and brainpower into this project because they WANT it to succeed. They have way more profitable jobs and DOD contracts they can be pouring. The case is a pain in the *** for them, but they are eager to accept the challenge, and I have been working with them for over a year. They have bent over backwards to get to this point, and I am going to let them work through their mistakes and errors and ugly surface finish (which I pointed out in an earlier post) until they can achieve the excellence I know they are capable of.
Let's give them a chance to do better. We have all been working on this tirelessly for a year and a half, and we don't have Hans Mezger on hand to answer questions nor a slew of Porsche engineers with blank checkbooks.
It is very important to me that the entire project be run right here in California, where I am close to all the parties involved.
That said, the foundry was more concerned with getting the gating right, and they took almost 3 weeks fiddling with it. When they poured #1, the one you saw in pictures, they were within 95% of perfection.
I am not defending them, but they did a pretty good job considering the only people that have poured these cases are PORSCHE and ME. Lots of things learned there on our part.
I posted pics of the first raw casting not to showcase how perfect it was out of the mold (it was far from perfect) but to showcase how far we have come.
The foundry has never given me a hard time; they have been amazing partners and frankly have put so much human capital and brainpower into this project because they WANT it to succeed. They have way more profitable jobs and DOD contracts they can be pouring. The case is a pain in the *** for them, but they are eager to accept the challenge, and I have been working with them for over a year. They have bent over backwards to get to this point, and I am going to let them work through their mistakes and errors and ugly surface finish (which I pointed out in an earlier post) until they can achieve the excellence I know they are capable of.
Let's give them a chance to do better. We have all been working on this tirelessly for a year and a half, and we don't have Hans Mezger on hand to answer questions nor a slew of Porsche engineers with blank checkbooks.
I agree having a good relationship with your suppliers is most critical. The piece has its complications although I don't see any use of chills or other standard practices to guarantee proper solidification of the casting. How far along was the cleaning process on that part? As I said I have done numerous parts like this far more complicated and usually we got it right the first time. Every shop is different though.
Looking froward to seeing your progress. Glad to see someone is doing this.
PS: Nice 928 or 829 racer. If you run into any foundry questions or problems you are welcome to PM me.
08-07-2017, 03:32 PM
#41
Banned
Thread Starter
I wasn't looking to put them down or steal any business. Just making an observation and an offer in case they don't follow through. I am happily retired.
I agree having a good relationship with your suppliers is most critical. The piece has its complications although I don't see any use of chills or other standard practices to guarantee proper solidification of the casting. How far along was the cleaning process on that part? As I said I have done numerous parts like this far more complicated and usually we got it right the first time. Every shop is different though.
Looking froward to seeing your progress. Glad to see someone is doing this.
I agree having a good relationship with your suppliers is most critical. The piece has its complications although I don't see any use of chills or other standard practices to guarantee proper solidification of the casting. How far along was the cleaning process on that part? As I said I have done numerous parts like this far more complicated and usually we got it right the first time. Every shop is different though.
Looking froward to seeing your progress. Glad to see someone is doing this.
Each cylinder spigot has a chiller, you can see the indentation and extra material left over inside the cylinder. Plus lots and lots of cores for each one.
The part I showed a picture of was mostly done but we knew the second it came out it was a throwaway for various reasons. It wasn't all wasted however; it is now the buck that the machinist is using to perfect his CNC routine.
FOR SURE will pm you if we run into issues. need an experienced second set of eyes on this!
08-07-2017, 03:32 PM
#42
Rennlist Member
08-07-2017, 04:42 PM
#44
Banned
Thread Starter
Wow, I will need to look into that. I own both air cooled and water pumpers and I find that hard to believe but hey, more power to him. Sounds like an air cooled version of a 962 engine.
08-07-2017, 04:43 PM
#45
Banned
Thread Starter