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First let me say thanks to all who can/will help, everyone so far seems pretty cool. My first question is in regards to a 390 engine I've come across, it's got a spun bearing and the guy who owns it was telling me it's a special piece, has a high performance manifold that is factory stock, supposedly will outperform most aftermarket units. It had an "S" cast onto the intake runner right near the distributor. Now is this the engine for an "S" code G.T., and if anyone knows, how good is this piece, and is it rare/valuable?
My second question regards stroking a FE engine, I know that by dropping a 428 crank in a 427 you getaround 454 cubic inches, any other crank swaps in the FE family you guys are aware of? Thanks to all for any help, and I look forward to getting to know you all!
Mike
 

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Any other casting numbers?
390 High Performance and Police blocks were cast with extra webbing in the main bearing and used thicker caps. They were solid lifter motors so no oil liffter galleries are present. These blocks featured a larger main oil gallery and the pressure relief valve is located at the rear of the main oil gallery and the camshaft plug. Pre '65 engines are cast for 2 bolt engine saddle mounting holes and pre '63 are cast without a provision for the alternator.
If the motor has a spun main bearing and its on the block side (not the cap) then I think I would stay away from it. If you put a 428 crank in it, it will be a 410 CI motor I believe. I hope I helped some what.
 

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My first question is in regards to a 390 engine I've come across, it's got a spun bearing and the guy who owns it was telling me it's a special piece, has a high performance manifold that is factory stock, supposedly will outperform most aftermarket units. It had an "S" cast onto the intake runner right near the distributor. Now is this the engine for an "S" code G.T., and if anyone knows, how good is this piece, and is it rare/valuable?
390 GT engines weren't TOO special, they had the same heads as were available on pickups (C8AE-H) and some of them had a 428 CJ cam shaft but it seems like they changed it after the first 2 years or so. With a performer RPM intake and a more modern dual energy style cam you'll have more flow and power.

My second question regards stroking a FE engine, I know that by dropping a 428 crank in a 427 you getaround 454 cubic inches, any other crank swaps in the FE family you guys are aware of?
The 428 crank is the most common as it is usually the easiest, you can also get a offset ground 390 stroker crankshaft for about $375 from http://www.dscmotorsport.com/crankshafts.htm I believe it uses slant six rods and a special piston
 

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The problem with putting the 428 crank in the 427 block is that you increase the chance for spinning an bearing. Because of the rod angularity and the forces applied on the crank and the brearing surfaces, the crank will be more likely to grab and spin. FE427 could back me up on this, on the Network54 site Dave Shoe (FE genious) explained it better than I have.
 

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Beg to differ but how can a 428 crank in a 427 block spin more bearings than a 428 crank in a 428 block. 428's do not have a rep for spinning bearings.
Have good machine work done and put as long an arm in there as you want. Good maintanence and good oil pressure will make any motor live.
The S intake is as close to an FE emissions intake as there is and common as dirt.
 

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Never heard of DSCMotorsports but the guy has that 4.02" crank for $375. Sounds pretty attractive for building a 420 out of a 390 (at .030" over). 428 Cranks seem to go for around $500 and they give you a hair less stroke than the o/s ground 390. (.036" less to be exact.) Of course you would have to futz with the Chrysler slant 6 rods and whatever pistons are required, but there is no replacement for displacement.
 

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You'll have to ask Shoe to get the best answer. But from what I can recall, with the added stroke, the connecting rod angle puts more force on the bearing surfaces. I know I know, its not a good explaniation, but thats what I can remember. Dave Shoe will be able to explain better than I.
 

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I have personally had 4 390s grenade due to spun bearings.These engines were all well used but still makes me leary.My brother also had his stock 69 428 CJ motor die a simuliar fate, so it does happen on 428s as well.If your going to run an FE motor other than a side oiler have someone who knows what their doing do all the oiling mods these engines need to live.The 428 crank swap will give you a stock 410 cube mill with factory parts.Just don't read the project FE's dead article in the archives.It sounds too familiar to me.
 

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There can't be any more angularity using a 428 crank in a 427 block. It is exactly the same as the 428 just has a larger bore. That does not change any rod angles at all. That would be like saying if you punced the 428s 4.13" bore out to the 427s 4.23" bore, that it would change the rod angle. It only changes the bore size and that's it while getting better oiling from the 427 blocks superior oiling system.
 

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Remember that all FE's should be run with a extra quart of oil, especially as the rocker arms shafts wear as the oil pump can pump oil to the top end faster than it can drain back, also a high volume pump can make the problem worse, FE's can run on very low oil pressure, I've read the designing engineers felt there was no problem with just 6 lbs of oil pressure at idle as long as it came up when you revved it.
I've also heard of 390's going 400,000 miles without being rebuilt so if things are right they survive just fine oil mods or not.
 

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One reason if not thee reason FE's have bearing wear problems in heavyduty/high performance/race applications is they are "top oilers"...they oil the valvetrain first then the bottem end....not good. This is why Ford developed the "side oiler" blocks(an extra oil galley(s) that feeds the bottem end directly). Those who would be in the know on how to make top oilers live are those guys who run/build 428 CJ's for NHRA stock and super stock eliminator. SA books Ford Performance book shows some tricks to help top oilers live. You can drop the 428 crank in a 390(along with the proper 428/410 damper and flywheel/flexplate). This makes a 410 with standard bore 390 an engine ford actually built for use in some mercurys. 410 pistons I believe are still available. Using .030 410 pistons with your 390 rods and the before mentioned 428 cranktrain pieces would give you a 416 ci engine. I would have the whole thing balanced for sure.
 

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It seems like a well prepped topoiler with the oil passages behind the cam bearings opened up would oil easily as good as the sideoiler, look at the oil path for a sideoiler it's not a gentle mains first oiling, the oil path is pointed to the cam bearings, the oil has to make a 270+ degree or so turn to get to the mains, it still has the topoiler paths it just also has the passage on the side to pump more oil right into the path between the mains and cam bearing At least with a top oiler the oil goes straight down to the mains albeit making a path around the cam bearing
 
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