So i've been doing to some research to find out what exactly the hell i have here, and have come to the conclusion that i have a 56 fairlane fordor instead of a 56 customline. And the biggest surprise of all(if the serial number on the driver side front pillar is correct) is that instead of a 292 y block, theres a 312 in there. According to the SN the engine code is 'P' which in 1956 was a 312. The 'P' code was only used twice before in '55 and '54. The model year code is a 6 so that tells me its a 56. Unless the previous owner slapped on a VIN plate to make it look legit. so now that i've shared that.. can i get some opinions on the 312? is it worth hangin on to or should I look for a 292 or 302 possibly? pros and cons? thanks Chris
You may want to check this out to verify:http://www.ford-y-block.com/technical.htm 1956 Fords confused people by using the same casting numbers on 292's and 312 blocks.If you have the running 312 you have the most desirable of the Y-blocks,the only downside to y-blocks these days are the expense to build one,but damn they have a sweet sound all of their own.Parts for the 289-302 SBF are about a third the cost of 292-312 parts.
Thanks ill have to do some more reading. It was a runner driver before i started taking the old electrical out. i guess i wont really know until i open her up.
There's not a YBlock lover that would take a 312 out to put a 292 in its place. There are lots of parts available for all yblocks and they may be a bit more expensive but you end up with sweetest sounding Ford of them all. I'll get off my soapbox now. Regards
don't know where you are located, but if you have a 312 that you do not want, I would be more than happy to help you offload it, lol!
Those old 312's are no good. I think you should take it out and call me. I'll haul it off for you. Probably even let you have a good 292 just 'cause I like you.
Actually, on teardown of that 312, you'll probably find cracks around the main bolts in the block. Common 312 malady. In that case, you build a 312 on and from a good 292 block.
Thanks all. i just wanted a few more opinions about cause all ive been reading is that 292 is an ideal y block. buuuuut if the 312 is what i have im gonna do my best to hang on to it and give it a nice rebuild.
As streetdreams said, when you tear into it, you might find out its a junk block. Just make sure to have the block magnafluxed before you start really throwing money around.
ya i heard that they are prone to crack at the main bolts. if the good lords willing and the creeks dont rise ill get into over the next few months!
An easy way to save a buck on the rebuild is to not let a Ch##v mechanic within a mile of it. The first thing some people want to do is throw away the cam and lifters, "because thats the way we do things". Send the cam out for a regrind, and resurface the lifters. They dont wear like the "other guys " parts do. If the damper is bad, it too can be repaired. The rockers can be refaced, and placed on new shafts. Pocket port the heads at home, and port to the gaskets. Dont forget to drill the steam holes to the new head gaskets. Mill the heads about .020, the little engine that could will really wake up.
For some reason when these 312 engines were first built, the factory thought they needed the mains tensioned down to 120-130 ft/lbs. This is the tension in the 56 manual. the clearance between the mains and the bolts is quite thin compared to 272-292 and this has probably led to why they are prone to crack. Most think now that 90 ft/lbs is sufficient. Nowadays as Don said, if it is cracked, it is not a problem just get the crank journals resized to 292 size and use a 292 block to rebuild it. The 312 bore is +0.080" over the 292. Some of the early 272s will easily accommodate the rebore also. My 55's 272 which was stuffed through someone leaving the engine for years with the air cleaner off easily went out to 292 +0.060". The gurus for these engines can be found over on y-blocksforever.com.hope this helps. Regards
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