89 951 engine overhaul

[Tom]

I'm holding out a little hope there, yes! (edit: well....) I'm far from a machinist though, so it's possible I fouled up the measurements enough that it's not the case.

I was under the impression the 100mm pistons were 100.00mm, but writing this out I'm realizing that's the bore, and presumably those Wossner pistons are 99.92mm. Gah! Maybe this is why that shop said no to boring... I guess the next best bet would those Mahles from earlier.

I think I posted pictures of what scoring there was - Maybe 2 lines I can catch total. I'm not quite sure what the depth threshold is for being able to feel it with a nail though.

I'm sure Chris can tell you what those pistons measure out to, but I don't know of any realistic way to know how much you'll need to bore to get past your score marks. But it's not zero, so think you'd have to get very lucky to stay within spec on stock-size pistons. Maybe there is equipment out there that can tell you, or some clever technique, but I think you'd realistically need to bore it to find out for sure. The standard one-over allows you to clean up most typical wear and scoring.

[Latitude48]

So, if C&D Machine (I've used them in the past for head work on an old Audi 5000S) can CORRECTLY hone an Alusil block (big IF I think), the Mahle pistons from LN Engineering would seem to be the better guarantee of removing any taper.

As an aside... questions for head honcho Tom:
1) If I am subscribed to this topic why don't I get email notifications when there are new posts?
2) The timeout period to remain logged in should be changed to infinite like RL. On more than one occasion I've been logged in, then got busy doing something else, only to come back and compose a response... but when I try to post I'm not logged in and everything I had typed is sent to the bit bucket. It just happened on this topic. Argh!

[Tom]

So, if C&D Machine (I've used them in the past for head work on an old Audi 5000S) can CORRECTLY hone an Alusil block (big IF I think), the Mahle pistons from LN Engineering would seem to be the better guarantee of removing any taper.

As an aside... questions for head honcho Tom:
1) If I am subscribed to this topic why don't I get email notifications when there are new posts?
2) The timeout period to remain logged in should be changed to infinite like RL. On more than one occasion I've been logged in, then got busy doing something else, only to come back and compose a response... but when I try to post I'm not logged in and everything I had typed is sent to the bit bucket. It just happened on this topic. Argh!

Agreed.

And re #1: this has been an on-going struggle to fix system-wide. But you can fix your own by clicking your name in the upper right, then profile, then edit profile, then the board preferences tab, then edit notification options. You'll see options for when to get email notifications, etc.

Re #2: excellent point -- has happened to me too. I just made a few changes that are advertised to fix that. Let me know if it keeps happening....

[four0four]

So, if C&D Machine (I've used them in the past for head work on an old Audi 5000S) can CORRECTLY hone an Alusil block (big IF I think), the Mahle pistons from LN Engineering would seem to be the better guarantee of removing any taper.

It's between them and Autosport in Ballard, if you're familiar? (I found at least some evidence they've done this before. I should just ask...)

Anyhow - is it common (...not unheard of?) for shops to claim they have capabilities like this without being able to back it up? I'm not particularly used to dealing with them, so I've no idea if it's reasonable to ask for their process. Would be very disappointing to end up with something that I could improve with felt and an-30 in my garage


wrt the timeout stuff - I haven't noticed it at all. Did some cursory googling: seems like phpbb likes killing sessions if your IP changes? This isn't too uncommon, and more likely to occur with mobile ISPs. Obviously I've no idea what Tom has the config set to, but maybe it's something to check

[Tom]

So, if C&D Machine (I've used them in the past for head work on an old Audi 5000S) can CORRECTLY hone an Alusil block (big IF I think), the Mahle pistons from LN Engineering would seem to be the better guarantee of removing any taper.

It's between them and Autosport in Ballard, if you're familiar? (I found at least some evidence they've done this before. I should just ask...)

Anyhow - is it common (...not unheard of?) for shops to claim they have capabilities like this without being able to back it up? I'm not particularly used to dealing with them, so I've no idea if it's reasonable to ask for their process. Would be very disappointing to end up with something that I could improve with felt and an-30 in my garage


wrt the timeout stuff - I haven't noticed it at all. Did some cursory googling: seems like phpbb likes killing sessions if your IP changes? This isn't too uncommon, and more likely to occur with mobile ISPs. Obviously I've no idea what Tom has the config set to, but maybe it's something to check

I have zero input on those particular shops, but have had more than my share of shops tell me there were able to do something, only to find out otherwise. A very highly regarded machine shop in my area got a fancy new EDM machine and offered to remove a couple broken studs from a 968 block. The ended up melting away a good portion of the water pump mounting area and turned it into scrap metal.

edit p.s., the platform uses cookies to keep you logged in I believe, and it did look like I had it configured to look in the wrong place for cookies on the server side. Time will tell. Let me know if it continues to be an issue.

[Latitude48]

edit p.s., the platform uses cookies to keep you logged in I believe, and it did look like I had it configured to look in the wrong place for cookies on the server side. Time will tell. Let me know if it continues to be an issue.

The system still logs me out after a (unknown) period of time... less than an hour I believe.

Regarding Galen's engine rebuild and honing Alusil there are quite a few other engines (Audi, Mercedes to name two) that use Alusil, so I guess it's not out of the question that C&D would be capable of this work. I hope they are. Their shop isn't that far from me, so maybe I'll drive up there and have a chat.

[Tom]

edit p.s., the platform uses cookies to keep you logged in I believe, and it did look like I had it configured to look in the wrong place for cookies on the server side. Time will tell. Let me know if it continues to be an issue.

The system still logs me out after a (unknown) period of time... less than an hour I believe.

Regarding Galen's engine rebuild and honing Alusil there are quite a few other engines (Audi, Mercedes to name two) that use Alusil, so I guess it's not out of the question that C&D would be capable of this work. I hope they are. Their shop isn't that far from me, so maybe I'll drive up there and have a chat.

I'll PM you for more info. There's no time-based log out that I know of.

[gruhsy]

Any reason why you don’t just go with Nikasil from Millennium Technology?

They 100% know what they are doing. Nikasil is a far better option than gambling on Alusil.

Purchase the Nikasil compatible pistons from Chris White and there will be no doubt the work will be done correctly. You will end up with a cylinder bore that is far more round than can be achieved with Alusil.

Shipping a block to them is not that hard within the US.

https://www.millennium-tech.net/

[Tom]

Any reason why you don’t just go with Nikasil from Millennium Technology?

They 100% know what they are doing. Nikasil is a far better option than gambling on Alusil.

Purchase the Nikasil compatible pistons from Chris White and there will be no doubt the work will be done correctly. You will end up with a cylinder bore that is far more round than can be achieved with Alusil.

Shipping a block to them is not that hard within the US.

https://www.millennium-tech.net/

This would sure get my vote.

[Latitude48]

Any reason why you don’t just go with Nikasil from Millennium Technology?

Cost might be an issue. I contacted them for a quote and got this reply: "The cost for overbore and plating is $1,454.90. If you desire Torque Honing the additional cost is $199.95. Our current turn time is 30 Business days."

I do agree this is the best option in the long run.