Xpost: Are stock pistons compatible with an iron sleeved block?
06-17-2016, 10:13 PM
#1
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Xpost: Are stock pistons compatible with an iron sleeved block?
crossposting this from the NA forum since there are a lot more guys with sleeved motors here. This is in regards to a 951 motor I am building.
I spoke with Duffin Engine service in San Antonio today, they are familiar with building 944 engines but my conversation with them today was brief do to my schedule and it raised some questions they were not able to answer.
For one, although they have done many 944 engine, they claimed to have never dry sleeved a 944 engine, or any alusil engine for that matter. They also said they would not install darton sleeves on any motor, period and would not elaborate why.
Secondly, they raised doubts that there would be enough meat on the 944 block's wall to successfully dry sleeve, which we all know is not the case.
They also stated the factory alusil pistons would not be compatible with an iron liner, can anyone shed some light on that? If that is the case, I would probably go with new wossners.
In any case, they quoted me 320 dollars labor for the installation, which I thought was an excellent price. Any recommendations on some good sleeves that wont break the bank? I don't know if there is really a great difference between them, I was looking at some melling sleeves like these:
https://www.summitracing.com/parts/mel-csl116/overview/
Also just a question, but what is keeping a sleeve that does not have a flange from moving besides the interference fit between it and the cylinders? Is it recommended that I have the block counterbored and get flanged sleeves, or have people successfully used straight flangeless sleeves in a 951 motor?
Would anyone like to address any of the comments Duffin made to me? I don't know that much about the details of sleeving the block but I have made up my mind that this is the route I am going.
Thanks guys!
edit: is it possible to safely go to 104mm on dry sleeves?
I spoke with Duffin Engine service in San Antonio today, they are familiar with building 944 engines but my conversation with them today was brief do to my schedule and it raised some questions they were not able to answer.
For one, although they have done many 944 engine, they claimed to have never dry sleeved a 944 engine, or any alusil engine for that matter. They also said they would not install darton sleeves on any motor, period and would not elaborate why.
Secondly, they raised doubts that there would be enough meat on the 944 block's wall to successfully dry sleeve, which we all know is not the case.
They also stated the factory alusil pistons would not be compatible with an iron liner, can anyone shed some light on that? If that is the case, I would probably go with new wossners.
In any case, they quoted me 320 dollars labor for the installation, which I thought was an excellent price. Any recommendations on some good sleeves that wont break the bank? I don't know if there is really a great difference between them, I was looking at some melling sleeves like these:
https://www.summitracing.com/parts/mel-csl116/overview/
Also just a question, but what is keeping a sleeve that does not have a flange from moving besides the interference fit between it and the cylinders? Is it recommended that I have the block counterbored and get flanged sleeves, or have people successfully used straight flangeless sleeves in a 951 motor?
Would anyone like to address any of the comments Duffin made to me? I don't know that much about the details of sleeving the block but I have made up my mind that this is the route I am going.
Thanks guys!
edit: is it possible to safely go to 104mm on dry sleeves?
Last edited by Dougs951S; 06-17-2016 at 11:00 PM.
06-17-2016, 11:00 PM
#2
Rennlist Member
Dry sleeves work fine if installed PROPERLY as we have demonstrated over and over again. I am using Melling 592274 on the latest build which is a flanged sleeve. I have never used the oem pistons in a dry sleeve but I have heard of them being used without issue. Again if done properly, you can go 104 mm on the 2.5L block.