just got a doner engine and want to check the compression before i take the heads off. its a 59 ab. what should be a good range in compression? how many times should it turn over to get a good read? hopefully it will be good so i can bild my 1/8 x 1/8 motor 272 clay smith cam adj lifters and lincoln duel coil ignition,2 94s and lightend fly wheel. thanks any info would be great. billy
3 or four times should be enough, watch the guage ,and when it stabilises that will do. if its stock I think 80-90lbs would be a good reading, less than 60, not so good.
you also need to watch the differences between the cylinders. a healthy engine should show no more than a 10% range from highest to lowest. You also should pull all the plugs while checking, and after the first go around, put a couple squirts of oil down each cylinder and do it again, each cylider should show and increase from its dry reading. If there is a substantial increase, it indicated worn or sticky rings. Cylinders that show no change would indicate sticky, fouled or burnt valves.
Stock Ford spec for 59A-a=A heads 110, 59A-B heads 115 (never noticed that before, slightly smaller chambers!) plus or minus 10.
ok just got done with compression check and i got 115-125 only one cylinder being 115 or so the rest real good i guess. here the scoop on the motor got it for free from a friend it came out of a 40 coe the motor is a 59 ab block heres the wierd part it has a 39-40 distribuator with three hole cam cover so thats cool for me because i'm going to put my lincoln duel coil ignition on it. it also has the adaptor so the lincoln will go on there and the stamping on the block on the bell housing is c4 8 1 . i wonder if its has been beefed up since it was in a big coe truck? also cool it has double groove water pumps and genartor with cool 6 blade fan. i cant wait to take the heads off to see if has a relived block. my plans for it are for my roadster 272 clay smith cam adjustible lifters and a weiand two pot mainfold and put exaust spilters in it and chrome my oil pan. anyone have good source for cam grinding in so cal? or can i just go to clay smith and get one? and lifters. thanks billy i'll take pics of it.
Those double sheave truck water pumps used to be highly prized by builders of blown engines as they had sealed roller bearings versus the passenger car bushing types. And the double sheaves could be good for double belts driving the blower.
Have a old tired 52 F100 the most compression is 40 lbs. Truck runs down the expressway at 65 and doesnt heat up so I dont plan on changing it anytime soon.
I wouldn't run the exhaust splitters if I were you. Ours fell out and some friends that also run at Bonneville (and have held the record in their class) had their's come loose, block the port and keep them from setting a record just this past year.
Just a thought here...why build on what seems an unusually good running stocker?? Keep it as a spare engine or another project, build on a block that needs to be gone through from scratch. A spare runner ready to go is a great thing. Am I crazy?
I have a back up its sleved low compression smoker the one i have in my car is a oil buring smoker. I got this one for free so i will build it . A good motor is getting hard to find.
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