HellYeah Posted June 15, 2015 Report Posted June 15, 2015 I´m about to test a new camshaft and a aluminium head on my -47 230 cui engine. But I´m not sure what torque to use bolting down the alu head. I´m told I can use the same torque as on the stock cast iron head. I know from other engines that the torque for alu heads usually are lower than for cast iron heads... Also I do not have new valve lifters available right now. Can I install a new cam using the "old" lifters, or will this ruin the new camshaft? Quote
Dave72dt Posted June 15, 2015 Report Posted June 15, 2015 Wait for the new lifters. Lifters and camshafts wear in to each other. Using the old lifters that have already developed a wear pattern may ruin your new one. Lifters are harder than the cam so the break-in wear will be on the cam and would end up matching the old lifters. When the new lifters go in, a second wear pattern to match the new lifters would occur. The head manufacturer should have a torque spec, pattern for the application, if they are still in business. Sometimes the gasket manufacturer will have torque specs listed for the different applications of head material for that particular gasket. They may also recommend a particular type of gasket material depending on iron or aluminum head. Quote
greg g Posted June 15, 2015 Report Posted June 15, 2015 I had my Edmunds head torqued to 65 #ft. With the aluminum head it is critical that the proper sequence be used and the torque application be done in increments. after snugging the bolts, I did 30, 40, 50, 55, 60, 65. Then it should be re-torqued again using the proper sequence after a runnning cycle where the engine reaches full operating temp. Quote
T120 Posted June 15, 2015 Report Posted June 15, 2015 (edited) I don't have an aluminum alloy head. I have noticed in my Chrysler shop manual under engine tune-up there is a note: "Iron cylinder heads should be tightened while engine is warm. Aluminum alloy cylinder heads Must be tightened while Cold. No torque difference is mentioned. Edited June 15, 2015 by Ralph D25cpe Quote
greg g Posted June 15, 2015 Report Posted June 15, 2015 One wonders how one would warm up an engine without the head in place. Quote
T120 Posted June 15, 2015 Report Posted June 15, 2015 One wonders how one would warm up an engine without the head in place. ...It was in the "tune-up" section of the manual Quote
HellYeah Posted June 15, 2015 Author Report Posted June 15, 2015 Wait for the new lifters. Lifters and camshafts wear in to each other. Using the old lifters that have already developed a wear pattern may ruin your new one. Lifters are harder than the cam so the break-in wear will be on the cam and would end up matching the old lifters. When the new lifters go in, a second wear pattern to match the new lifters would occur. The head manufacturer should have a torque spec, pattern for the application, if they are still in business. Sometimes the gasket manufacturer will have torque specs listed for the different applications of head material for that particular gasket. They may also recommend a particular type of gasket material depending on iron or aluminum head. I will order a set of new lifters then. The head manufacturer closed in 1952 so no more information there I´m afraid.... I had my Edmunds head torqued to 65 #ft. With the aluminum head it is critical that the proper sequence be used and the torque application be done in increments. after snugging the bolts, I did 30, 40, 50, 55, 60, 65. Then it should be re-torqued again using the proper sequence after a runnning cycle where the engine reaches full operating temp. Edmunds will probably be the closest to my head (Tattersfield). If 65 #ft worked in your engine it will probably work fine on mine as well. I guess the sequence pattern will be the same as the stock head... Quote
Don Coatney Posted June 15, 2015 Report Posted June 15, 2015 One wonders how one would warm up an engine without the head in place. I was able to warm my engine up quite a bit by adding dual carburetors, dual exhaust, dual points, lumpy cam, milled head etc. Quote
greg g Posted June 15, 2015 Report Posted June 15, 2015 Don, have you finished reinstalling your fresh electrical smoke?? Quote
Andydodge Posted June 15, 2015 Report Posted June 15, 2015 I'd also be careful about using an alloy head with the standard copper sheet head gasket as aluminium and copper are not a good combination.........I had a Best Gasket brand gasket set and requested a steel gasket be included in the set.......I was going to use a light spray of gasket sealing compound or even silver paint which I was told also worked well.......I'd suggest contacting Earl Edgerton who makes the Edgy Heads or even Edelbrock as their finned heads for Frods would also have similar requirements........andyd Quote
Plymouthy Adams Posted June 15, 2015 Report Posted June 15, 2015 IF using head bolts and or studs/nuts for that matter..with the aluminum head I would be much concerned about a hardened washer to displace the torque and not gall the metal beneath a head bolt/nut... Quote
deathbound Posted June 16, 2015 Report Posted June 16, 2015 (edited) In my '36-'42 Plymouth service manual...."A final tightening should be made on engines with cast iron heads when the engine has been run sufficiently long to bring all parts to operating temperature. For engines with aluminum heads, check tension after the engine has been run and cooled and while it is still cool. Using a torque wrench, tighten cap screws to 65-70 foot pounds; nuts to 55-60 foot pounds." I know the OP has a '47 230 ci engine, for which the above info may be different, due to different compression ratios (*****EDIT:torque specs vary by fastener size, so maybe the above specs are good????*****). There was no mention about different torque specs for cast iron heads vs aluminum heads....only cap screws (bolts) vs nuts (studs). I have an Edgy aluminum head with ARP studs, & yes, they have hardened washers. Edited June 16, 2015 by deathbound Quote
martybose Posted June 16, 2015 Report Posted June 16, 2015 I have an Edmunds head on my motor with ARP studs that have fine thread nuts, so i used the 60 lb. spec for torquing. But it is worth noting that I would take the car out for a drive and then retorque the head while still warm. It took me 3 times before none of the nuts would move when torqued. Marty Quote
deathbound Posted June 16, 2015 Report Posted June 16, 2015 I have an Edmunds head on my motor with ARP studs that have fine thread nuts, so i used the 60 lb. spec for torquing. But it is worth noting that I would take the car out for a drive and then retorque the head while still warm. It took me 3 times before none of the nuts would move when torqued. Marty Curious, if you re-torque while the aluminum head is still warm & the head contracts slightly as it cools, is the torque not accurate anymore? I was under the impression to re-torque the aluminum head after it has cooled (and contracted), so the torque is more accurate. Quote
T120 Posted June 16, 2015 Report Posted June 16, 2015 Following is the note in the 1937 Chrysler Shop Manual regarding tightening aluminum alloy heads as supplied as an option by Chrysler back in the day. My 1942-46 Chrysler Shop Manual has the same recommendation... See paragraph 2 Quote
HellYeah Posted June 16, 2015 Author Report Posted June 16, 2015 Thank´s for posting all that information folks! Great help! :-) Quote
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