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Anyone use alumabrite (wheel acid)..to really clean these engines???
Napa aluminum brightner + power washer works wonders and isn’t too much work.

As for “matching numbers”, my understanding is that Alfa engines are not number matched to a chassis, so no real way to verify if it was the original.
 

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Discussion Starter #63
Thanks...is the date of manufacture part of the engine number? If so how to decode? Or is there a date code somewhere on the engine?
 

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There’s a site called the duetto register which shows which engine numbers were given to which cars, but doesn’t necessarily tell what year or anything specific as far as I know
 

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Discussion Starter #67
Well, I guess this engine removal thread has now evolved into an engine rebuild/freshen thread. Overall, everything looks pretty good. There are some indications of PO attempting excessively to start a noncompliant engine as evidenced by some minor scuffing on the bearings crankshaft journals, pistons and cylinder walls. Polish crank, hone cylinders, and install new rings and bearings. Additionally, I checked the valve clearance and recorded the results. Can someone provide the specs for clearances on the intake and exhaust valves?
I must say I am well impressed with the design and construction of this little engine. Forged steel cank, beefy connecting rods, robust block and hemispherical combustion chamber design.coupled with a valvetrain which appears as though it would be incredibly stable at high RPM. (Huge potential for horsepower production) Are the pistons forged or cast? Where can I purchase rings and bearings at a reasonable price? Are upgraded rod bolts such as ARP available? If so, from whom? I may just go ahead and do some mild camshafts as well?
1638527


Any and all information is greatly appreciated,

Thank you,

Gary Ellis
 

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Well, I guess this engine removal thread has now evolved into an engine rebuild/freshen thread. Overall, everything looks pretty good. There are some indications of PO attempting excessively to start a noncompliant engine as evidenced by some minor scuffing on the bearings crankshaft journals, pistons and cylinder walls. Polish crank, hone cylinders, and install new rings and bearings. Additionally, I checked the valve clearance and recorded the results. Can someone provide the specs for clearances on the intake and exhaust valves?
I must say I am well impressed with the design and construction of this little engine. Forged steel cank, beefy connecting rods, robust block and hemispherical combustion chamber design.coupled with a valvetrain which appears as though it would be incredibly stable at high RPM. (Huge potential for horsepower production) Are the pistons forged or cast? Where can I purchase rings and bearings at a reasonable price? Are upgraded rod bolts such as ARP available? If so, from whom? I may just go ahead and do some mild camshafts as well? View attachment 1638527

Any and all information is greatly appreciated,

Thank you,

Gary Ellis
It was quite an advanced design when it was first made, and had a lot of very "racy" features for a mass production motor of its day. Nevertheless, it's rather outdated in 2020, so you are never going to make 150hp/l naturally aspirated like some Honda K series motors can with proper mods. But it's miles better than anything from a U.S. manufacturer from the same era. The valvetrain can be made to handle pretty high revs, but you won't make much power high up without other head modifications.

Pistons are cast, but fairly strong. Several suppliers can sell you forged pistons, though really only worthwhile if you are trying to change compression ratios. No real reason to upgrade rods or rod bolts unless you are doing a very aggressive high output build. They can handle anything a naturally aspirated street motor could throw at them. You can, however, get forged rods and ARP bolts for $300 (Chinese built from a company called "Maxspeeding", available on ebay), or spend $1,000+ for Carrillos that utilize even higher end bolts. Quite a few companies sell engine components, but Spruell motorsports has nice packages at varying levels of aggressiveness for fairly reasonable price- they used to be a more full service Alfa shop, but they mostly focus on motor components these days.

Weak points of the motor are liners and head gaskets due to the very open deck and the design of the liners. The liners can shift (causing blown head gasket) or crack under very high cylinder pressures. Some old shop manuals recommend torque values that are too low for the head bolts. There are quite a few threads here about head torque. Higher torque helps, but does not 100% solve the head gasket/liner limitation.
 

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Discussion Starter #69
I am considering the addition of a turbo in the future. Is there anyone with recent experience in that area? A kit available? Nealric, thank you sir.
Gary
 

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I am considering the addition of a turbo in the future. Is there anyone with recent experience in that area? A kit available? Nealric, thank you sir.
Gary
No kits. There have been kits in the past, including a factory turbo kit for the Alfetta (same motor). I wouldn’t bother with any of the old kits. They are quite outdated at this point. Plan on some fabrication work.

Several turbo thread builds on the bb (including mine), but I inherited the actual turbo kit on my car.
 
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