Cylinder Boring/Coating

[Speeddog]

Blast from the past.  How many of you remember the aluminum block Chevy Vega?

<raises hand>

IIRC, they did OK as long as you didn't overheat 'em?

[64duc]

 In 1962 Oldsmobile built an aluminum block v8. I was 215 cu/in 215 hp. Bad azz little engine in the 2400 lb Cutlass. It too was a great performer until you overheated it. Exactly what happened to mine.

[scott_araujo]

Were these aluminum car engines prone to overheating because of insufficient cooling?  Or just so much fun to flog it just sorta happened a lot ?

Scott

[Mr Earl]

In 1962 Oldsmobile built an aluminum block v8. I was 215 cu/in 215 hp. Bad azz little engine in the 2400 lb Cutlass. It too was a great performer until you overheated it. Exactly what happened to mine.

That 215 cid V8 engine was sold to British Leyland, and used by them in Land Rover vehicles, perhaps even to date (haven't followed it.)  I never knew what the cylinder technology was, though.

GM lopped off 2 cylinders, turned it into the odd-fire Buick V6 cast iron motor that went into the 1960s Buick Special, then sold it later to Jeep, and it went into CJs as the "Dauntless" V6.  Buick bought it back...  oops, precipitously off-topic, sorry.

[Langanobob]

Were these aluminum car engines prone to overheating because of insufficient cooling?  Or just so much fun to flog it just sorta happened a lot ?

Scott

Scott, I recall a questionable source telling me that the overheating issues had something to do with heat flow from the combustion chamber through aluminum being faster than through cast iron.  Not sure if that makes sense though if the cooling system was adequate to begin with.

Bob

[Porsche Monkey]

Nikasil was developed by Mahle and used in Porsche's in the late 60's.

[d6a9p6]

650 Pantah engines had it in 1985, I think all Pantahs starting in 1979 had it. Nikasil that is.  Don

[Howie]

Scott, I recall a questionable source telling me that the overheating issues had something to do with heat flow from the combustion chamber through aluminum being faster than through cast iron.  Not sure if that makes sense though if the cooling system was adequate to begin with.

Bob

The biggest cause of overheating on those engines was the lack of phosphate free coolant in the US and knowledge that phosphate free coolant was needed for aluminum.

[ducpainter]

The biggest cause of overheating on those engines was the lack of phosphate free coolant in the US and knowledge that phosphate free coolant was needed for aluminum.

Was/is it a heat transfer issue or a corrosion issue on the aluminum?

[Howie]

The aluminum would slowly corrode in hotter areas, like the cylinder heads, combine with the phosphate to form aluminum phosphate and the aluminum phosphate would deposit itself in cooler regions like the cylinder block and radiator.  Silica in conventional coolant played a role in cooling system this too, though I don't remember what the problem was. 

[ducatiz]

650 Pantah engines had it in 1985, I think all Pantahs starting in 1979 had it. Nikasil that is.  Don

1980.  yes.

[ducatiz]

Blast from the past.  How many of you remember the aluminum block Chevy Vega?

my bud in hs had one, we loved it.  we dropped the engine and put in a 327 small block..  i forgot how he got the money, but he picked up an Edelbrock dual carb intake setup and holley 600 carbs.  it sounded like a friggin elephant. 

i think it broke the differential... rofl

look at this one

Cosworth Vega on ebay

[scott_araujo]

So with nikasil....

Do you need to overbore a few thousands before plating to get the right tolerance?

Do you need to hone the nikasil after you plate?  Or the cylinder before you plate it?

Any issue on seating rings, etc.?  Are the rings made of special material to seat and play nicely with nikasil?

Scott

[ducatiz]

So with nikasil....

Do you need to overbore a few thousands before plating to get the right tolerance?

Do you need to hone the nikasil after you plate?  Or the cylinder before you plate it?

Any issue on seating rings, etc.?  Are the rings made of special material to seat and play nicely with nikasil?

Scott

you have it mostly right.  they just remove the old coating and then check the surface (if any damage) the new coating will be over and they will use your pistons to hone it down. 

you don't need to hone it, you will just get it angry.

these guys are the ones i used.  they have a very good rep

http://kustom-kraft.com/NEWNIKASIL.html

[scott_araujo]

Cool, thanks