you can NOT build a stock 460 block to 834 cid if you actually look you will see that is using all aftermarket blocks and tall deck stuff plus the 800+cid stuff is using 5.0" bore spacing and they barely even resemble a 460.
Orange juice there is no factory casting number that you can safely say can be bored to 4.5" bore. you might find one after searching through a bunch and doing sonic mapping to find a block you would only have to sleeve a couple cylinders to be safe at that bore size. The other way of reaching 572 is 4.3" stroke x 4.60 bore and NO you can't bore a stock block that far without hitting water. 4.5" is .140" overbore and basically any factory block over .060 should be sonic tested you can't assume any of them will go beyond that safely.
Can it be done? Yes but usually by the time you pay for the sonic test, pay to have all the machine work done that it will need anyway and pay to have at least a couple cylinders sleeved you are not far off of a aftermarket block like an A460 that has 4 bolt mains, better iron, siemese bores allowing up to 4.600 bore safely (most will actually go a little further and IDT claims 4.7) and has a much superior oiling system. I have seen a few factory blocks bored that far but when you check the wall thickness they are scarey thin and usually will cause over heating issues on the street if your thinking along those lines.
Actually we build 589cid out of stock blocks. It is not in the bore but the stroke that we get the cid. The bore is just over .080 and yes you want to sonic check the bores to see if they can handle the bore we you get at or around .080. We build these engine for all kinds of applications and they work and hold up really good.
Last edited by monsterbaby; 05-13-2008 at 11:11 PM.
Reason: removing advertising
Thanks for all the input everyone. I was just thinking if I were to buy a 460 it might be fun to bore it out to something larger to gain some extra HP. I'm no expert at this, but what's a good safe size could I increase it to and still be reliable if a 572 is questionable? Something smaller?
honestly IMO a 521 is a great compromise for the street between increased CID and dependability. use a 4.3" stroke with a 6.8" rod and .030 overbore and your within safe bore limits on the factory block without question and the parts are easy to get.
you can always get this [URL=https://secure.pawengineparts.com//552_Ford.html[/URL] ....
this is what i have '77 swb f-100 custom that had '76 crown vic/lincoln 460 that I ported and polished the heads gasket matched the intake and exhaust ports, bored it out to .030 over, and chamfered the stock crank ran truck rods and low dish pistons with NO2 reliefs, long tube hedman headers 3" dual exhaust with connector h pipe and 2 chamber flowmasters ... at 5800 I was making 566 hp and 660 lbs tq through a c6 with a 1200 stall converter 4" drive shaft 3.08 dana 44.
255 65 15 fronts
275 60 15 rears
The above engine would be a 466cid. To get 496 you would have to stroke your crank to 4.1 with a .030 overbore. Then your stock rods wouldnt work anymore. Those are impressive numbers out of a 460. Where did you dyno that at? If your getting that much power out of a basically stock 460 I need some lessons please!!
As far as what is a good engine for a tow truck? Go with the 4.5 stroke! I really like the 545 or 557cid. The 545 is a .030 overbore and the 557 is a .080 overbore. I dont mess around with the 4.3 stroke, if i am going to build a stroker I am going to build a stoker not half way. If it was strickly a tow truck I would go even with a 4.6 stroke. We are not talking about a high rever here we are talking about brute power and torque. The average horse and torque out of a 4.5 stroke is almost 40 horse and 40 torque across the board over a 4.3. Average torque under 3500 rpms is what the tow trucks need. We have done these big engines for several years and they hold up good with the 4.5 or 4.6 stroke. You only have problems with the long stroke over like 7000 rpms or over 800 horse or with boost. There alot of veriables to the problems but 460s are not like 302s with a short deck. They have tall decks and the 4.5 stroke dont put alot of side load on the bores like everyone thinks. We have sucessfully run 4.75 stroke in some of our truck pull and mud racer engines with iron heads and have averaged around 670 torque with a peak of 745 foot pounds and they have worked great. I have considering trying a 5'' stroke on my next build but I think I am starting to push the limit with these 10.3 deck. I will probably stay with the 4.75.
yes but long stroke requires a fairly short rod and your rod ratio gets out of wack and they DO side load the pistons, I have seen 4.5 stroke 6.7 rod engines with 10,000 miles needing complete rebuilds to suggest running a 4.6 or bigger stroke on a street engine is just not smart at all. and to run longer then 6.7 rod on a 4.5 stroke you have the pin into the oil hole and thats even using 1/16th rings. so you now have the issues associated with that just like a small block with a short deck height of burning oil.
And if you really know these engines you also know that with a 4.75" stroke you can no longer run the factory internal oil pumps without issues 5" you are guaranteed to need dry sump or at least external oil pump and starting to push clearance issues.
For longevity on a tow truck or any street driven engine you stay with a 4.3" stroke and leave the 4.5" and bigger stuff to the race guys.
I know you have butted heads with the guys on another big block ford forum but you might want to read the experience over there from some of the best known engine builders in the country on running 4.5" and longer stroke combo's
Now with that being said I have to agree the post above tim's is shall we say rather an exageration? and PAW engines I wouldn't recommend to my competition at a race they are not exactly known for good quality machining everyone I have known that has bought components from them that were machined had to take them in and have them re machined to get the specs right. and getting 1.21hp per CI is really impressive especially at 5800rpm and still be able to run through a convertor that has LESS stall then stock. Basically most of that post has a lot of just plain wrong info in it.
What are you talking about??? Your wrong! Actually the stock style pump was used! We are running a 6.8 rod or a 6.7 rid in both instances. Which is not a short rod. Man for somebody that is cutting on me you would think you would bring some fire power here. And also we have we have several 557cid tow truck engines going on 100k without problems. And for that matter we have some 347s that are above 100k in street applications. And another thing about THE BEST KNOWN builders, they are best known becuase they are biggest not nessesary the best. They are engine builders here in michigan that rock and roll that have never been heard of. Becuase they dont have big sponcers dont mean they arent as good as the other boys that build. Also you would think you would know that there are ways of build cid other than the 4.3 stroke and 140 overbore. Have you ever built a 460 dude?
So maybe all the old timers need to come out of there rutt thinking and move over to some fresh thinkers. I am not new to this business either but I havent been in it for 40 years either only 17 years. As far as rings being in the pin who cares? It is a pain to assemble but again we are not putting rings in them all the time.
WOW... I guess MonsterBaby knows nothing about 460's... No Offense but I know who MB uses to get some of his stuff and they are pretty top shelf group of guys. They have answered so many of my questions and gave me great service. I have never heard them put anyone down.
You say "You only have problems with the long stroke over like 7000 rpms or over 800 horse or with boost." Granted I am a truck puller so maybe I am biased but who really needs an engine that big and want to keep it low in the R's and HP? We do have a small engine (468CID) because of class rules but even if we move up I am sure that we would still be North of 8K. I don't know what MB ran is Mud Truck at but I would guess he was turning some serious R's as well.
Just my opinion. Take it for what you paid for it.
I built a 545 for my 79 F350. Used a Scat kit of a 4.5 stroker crank, 6.7 H rods and dished forged aluminum pistons. This combo gives 10.5 to 1 compression ratio with aluminum John Kasse Super Cobra Jet heads. I used a mild Comp Cam Extreme Energy cam, hydraulic lifters and roller rockers. I topped it off with an Edelbrock RPM Air Gap intake & a Holley 750 double pumper. It dyno'd at 500 HP at 4500 RPM and over 600 ftlbs torque from 2000 to 4500 RMM.
With the way I set this up, if I decide I want more HP, etc - basically all I have to do is change the cam and or add nitrous.
I've had this for over a year and so far no problems or complaints.
Hey, when I read this old thread, I just had to revive it. It's relatively easy to build a 4.6" stroke, .080 over, stock block 460 stroker, that will yield 570 cu/inches. Ford Racing sells a 4.3 inch stroker crank with a 2.5" rod journal diameter. (part no. M-6303-A514) By offset grinding that crank down to a 2.2" rod journal diameter, you get yourself a 4.6" stroke crank. Then you simply buy the common 6.8 inch stroker rods and 1.25 inch compression height pistons that normally are used with a 4.5 inch stroker crank. These are designed to fit in an early 10.30 deck block. The key is to use a 73 and later 460 block which has a 10.322 deck height and then mill .020 off the top of the pistons to make it all fit. That, combined with a head gasket that has a .043 - .050 compressed thickness puts everything in the right place for good quench and safe piston to head clearance along with more torque than you've ever dreamed of.
I'm rebuilding the engine on a '90 F250, it has the 460 in it. I've rebuilt a few engines--never this big--but have some simple questions. This truck is used mainly to haul wood and pull wood trailers, I need a lot of torque! It currently has 4.56 Gears front and rear with a Detroit locker in the rear. It has the ZF 5 speed manual transmission in it. What do I need to do / what parts do I need to get this engine to get 400+ ft pounds of torque and about the same in horsepower???
I laughed my simple **** off at these idiots. Hey Rob, Have you ever built a 460?
The first 460 I built was a nothing fancy 466 (stock D1 block .030 over), stock crank and truck rods, Speedpro H535P pistons ~9.3:1 comp with block and heads decked .010, Ported D3 heads, Comp x4262h cam with matching springs 7* retainers and locks, straight up double roller timing chain, Weiland Stealth intake, 1" open spacer, 750 Holley vac sec, 1 3/4" primary headers and a factory duraspark ignition.
This was about a 375-400hp engine with about 450 torque and I got 10-12mpg with 4.56 gears and 38" tires.
On your build Id consider something more like a Edelbrock performer (not performer RPM or airgap) for more low end power. This is a good, reatively cheap, build that will last a long time and make very reliable horsepower.