Hello: I did a search on this great site prior to posting this: Listed below is a well written article of how the inherantly thin walled 427 Side Oiler SHOULD NOT be overbored past factory bore. Fair Enough. If bores must be sleeved hen how in the world can there exist enough material to sleave and not enough material to over bore? Please imput and thank you again! http://www.mustangandfords.com/techarticles/15999_fe_quick_facts/index.html
I'm not sure when that article was written or by whom, but the part about not being able to overbore the 427 "side oiler" is a pretty much BS. I raced a 427 lightweight galaxie for over two years "back in the day" and started out with a std bore, went .020 and .030 with no problems. As for the 406 with "cross bolt mains", this came out late in 62 as Ford had already been testing the 427 cross bolt block and manufacturing changes were easily done to the 406's. The 406 was built for NASCAR, and because they were having a large number of the 406's grenade at the track, they made the decission to change the bottom end design of the 406 prior to coming out with the 427. Best and possibly worst 427 blocks were the 68, as they could be run with hydraulic lifters and the block had a higher nickle content. IMHO
The forces from the piston/rings and the commbustion process is being contained by the iron bores (thats not the only job the bore does, there are several) and that requires a minimum thickness of iron to pull that off while maintaining concentricity during use. There are general guidelines for this cylinder wall thickness value and it can also vary between different engine types and intended use. The structural requirements to support an iron sleeve in an iron block are much diffent than that required to withstand the forces seen during use because the new sleeve is now doing the job of the original iron was doing. It is not uncommon to machine right through a cylinder wall in spots when resleeving a block with a heavy duty sleeve. Typical max overbore on 427's (especially since most of them are over 40 years old) is .030" and most guys building them these days won't go that far due to core shift and water jacket corrosion. Given what these motors are worth today and the amount of money needed to rebuild one correctly many places cost-justify the installation of all eight sleeves. This is especially true in cases where the original block is in the original car and the owner desires to keep it that way. -Bigchief.
Save your money, call Robert Pond Motorsports @ (909)376-2530. He makes brand new iron and Aluminum blocks and all the original short comings include the one NOT addressed by the Genesis or Shelby block have been fixed. You can bore his iron block to 4.375 (.142 over!) and its still .250 thick/.500 thick were the bores are siamesed. I believe they are around $3000.00. You can spend that plus more for a factory thin wall. Leave em to the restorers and get a real block. Last weekend at the Div.7 meet Robert ran 9.905 @ 136.50 with his NHRA legal AA/S Fairlane. His parts and info are the real deal, don't even waste your time or money on the factory blocks.
Some of the last 427 SO blocks were apparently "service" blocks that had been previously rejected & appear to have issues with wall thickness & core shift. Any 427 block should be sonic-checked with a calibrated tester, IMHO. Some will go .030, some more, many less. So far as that article was concerned, it was written by Jim Smart...you will find many comments on Ford boards concerning his "research" and attention to detail. The only thing I could add to BigChief's post is that when a block has to accept eight sleeves, you will often find that most surfaces on the block need to be remachined...and if it actually has to be furnace brazed to accept the sleeves, EVERY surface will be off. If an original block isn't needed, you will most likely be better off buying an aftermarket block like the Pond (though I've not seen one as cheap as $3000). The same gentleman who designed the Pond block is now in the process of finalizing a new Cleveland block, with improvements.
I am running a 427 bored .040 with a 4.25 stroke (488cid). While I have also been told that .030 is the max, if you have the block sonic checked you can get a better idea about the wall thickness. Genesis, Shelby, and pond all make blocks. The cheapest i've seen is $3500 for an iron block. Aluminum goes up from there. When All waqs said and done, I wished I would have gone new. My block is a '68 that came from a marine application(reverse rotation). The oil galleys for the cam were a problem. I had a hyd. cam in it, when we went to prime it on the stand the lifters wouldn't pump up. After some investigation(and a piece of wire) We found after we removed the cam galley plugs, there was about a 1" section that wasn't drilled through. Being it was a finished motor, we decided instead of stripping it down and drilling the galleys out, we put a solid cam in. Glad I did, it loves to run 7000+ rpm. I would also suggest A Blue Thunder intake and definately aftermarket valvetrain with end supports on the rocker shafts. If you have any questions, feel free to PM me, I have had several FE's and I just built the 427 2 years ago. Also, you need to spend some time at www.fordfe.com. Alot of racers and builders.
I second the FORD FE board comment from above; many, many experienced individuals there to learn from. http://www.network54.com/Forum/74182/
Having had a few Ford 427's I must say that FordFE.com doesn't have anything on the HAMB'ers! Great info above that is 100% accurate.
Cylinder Thickness class 101!! class is in session. I have had a lot of engines cross my doorstep and the 427 is one that stands out for this reason of thin ass cylinders. The blocks had a large overbore from the factory and the walls were sketchy at best. I have had quite a few of these engines in and I can only remember 1 at this time that had no sleeves. The after-market blocks are the way to go here. The factory sleeved blocks have constant thickness for the cylinder walls. This was a great innovation back in the day. It's as if the cylinders are blueprinted from the factory. Now the class starts with photos. These are parts of a cylinder wall that failed. All the pieces pictured are from the same cylinder and it doesn't take a rocket scientest to see the problem. Kinda scarey!! check it out >>>>.
Pro X5: Please explain what is meant by factory sleaved 427 SO Blocks? Blocks available from FORD with all 8 cylinders offered with replaceable sleeves? On thin walled blocks the Sleeves outer does or does not contact coolant? Thank you
Factory sleeved as in Factory made but not from Ford. Aftermarket! On thin wall blocks it is not uncommon to bore through the original bore ,in places, to get a sleeve installed. If a big cube motor is the desire I always recomend for my customers to use an after market block that is designed for the purpose. You will have a ton of dough in the parts that will go in the block so why chance it. A quote from me goes like this "You wouldn't build a $700,000.00 house on a limestone block foundation would you?? " >>>>.
I checked last night and Ponds iron blocks are $3495. Before he started making them we used 4.280 bore with HardBlock. A "good" factory block at 4.280 (.047) was typically .090-.100 thick on the non thrust side. Pond was originally involved in the Genesis deal, but when the second batch was gonna take twice as long, cost more money, and still not incorporated several improvements he wanted, he hired their pattern guy and took care of it. At the PRI show a couple years ago Warren Johnson was even impressed enough to stop and look and call Ponds block "impressive".
I have a horror story for you. I bought a 67 mustang with a 427 SO. I noticed that compared to the 428 this motor had a lot of balls. The motor ran hot but i thought an FE in a small car and that will happen. The guy that sold me the car told me the motor had some work done. Well to cut to the interesting part...my brother is driving the car, gets stuck in traffic on the 405 and the motor seizes. I have the car towed home and pull the motor. Take to the engine builder and we pull it apart. And aside from the broken rod and burnt piston i find someone had bored the block .050 over. They had used a set of .030 over chevy pistons. I guess racers did this back in the 80's. This was all a history lesson to me. I take a look at the castings on the block, a late 66 code dated block, original PI heads and the original dual manifold with code date original 650's. Big money for Cobra and shelby guys. I ended up with 8 sleeves in the block. Built back to std bore and the all original parts installed. The motor sits on an engine stand in my garage. My builder has been building engines for 35 years and told me he had never seen or heard of someone boring a 427 .050 over.
John: Good Lord! THe modern Aluminum FE Side Oiler blocks obviously are light and seemingly not that far off in price to a used vintage 427 Side Oiler block at 4000 approx....Its the replacable purpose build sleeves that will give this block enternity! I am seeing if a firm offers a cast iron sleeved moden side oiler block now.
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