I've been working on the Ford 521 as a side project for most of the year. It is getting closer and closer but the project has hit a lot of little potholes along the way. I had to design new tools and fixtures so I could work on the belt drive. This engine has a Danny Bee belt drive and none of my Jesel stuff would work. I've also had to design new tools to work on the valve train. I have a big collection of Mopar stuff but none of it works with the canted valves.

I had to get a custom damper from ATI for the engine so I could put the TDC mark on the driver side. The Danny Bee belt drive doesn't come with a TDC pointer and there is no space for it on the passenger side so I moved it to the driver side. The T&D rocker arms are a bit interesting to work on since everything is on compound angles.

It will be interesting to see how this engine runs vs. my old 514 Mopar. That engine made right around 900 hp with MW ported Indy EZ heads that flowed 365 cfm. The Kaase heads on this 521 flow 425 cfm and the ports are roughly 50% larger than the MW ports. But the 521 has a little less compression and a little less cam.

I also can't get a really good intake for the Ford. Trick Flow has a good design for the big Ford engine but it has been out of production for most of the year. I have an Edelbrock Victor for the engine but it doesn't appear to be a very good intake. I don't think the Victor will support more than 800 hp anyway. But I guess we'll find out soon enough on the dyno. All I need to do now is finish up the top end assembly and get it on the dyno.

Is that an iron or aluminum block?

Factory cast iron late model block. Interesting thing about the 460 blocks is they made them all the way until 1997. And the blocks cast during the 90's have longer cylinder walls which make them better for strokers. Late model 460 blocks are still fairly easy to find since they made so many of them. Lots easier to find than a good B or RB block. The 460 block is also really strong. We're planning to make 850 hp with this engine and the block doesn't need any prep other than ARP main studs and proper machine work.

What is the Bore and stroke of that 521?

With fords especially big ports want high compression and a big cam....and without both you can't have either.... but it'll still run well with lower compression as long as the cam is on the small side too.

4.390 bore x 4.300 stroke. I'm not too worried about the combination. We're using the parts that Kaase recommends and he has built a ton of these engines. Once we get some dyno time on it we'll start trying different things but the first build will follow the Kaase plan. The cam is his "small" one since we have a smaller engine, but the duration at 0.400 is 91 degrees so the intake valves are open more than 0.700 for a quarter rotation of the engine.

That'll be a fun build, and it is impressive how big you can go with the later model blocks, I think it's something like 557" without too much trouble.. Like you said, they put them in everything- 429's and 460's in vans, pickups, the medium duty F600/700, you name it, all through the 90's.

Andy, this 460 motor has interested me for years. My very first thought was a fabricated tunnelram and twin throttle bodies, running e85 would make a dynomite combo, especially if the 557 size is not too tough to do. A local racer / engine builder runs 598 cube 385 series Fords, dialing 7.80 in the 1/4 on gasoline. One of my last outings i was unlucky enough to race him, and he went 7.80 on a 7.80 dial.

Yeah I think a 4.500 stroke crank in a 0.030 over stock block makes 557. Aftermarket blocks can go bigger but I'm not sure how easy it is to find aftermarket blocks these days. Ford used to make the A-460 block but I think they stopped making it. We could've built a 557 but the 521 seemed easier. Stroker kits and pistons were available and the CR was in line with what we were trying to do.

545ci on that .030 combo.

You need to go .080 over to 4.44 for the 557.

On Kasse web site, possible 659 cu in combo, 4.70 bore 4.75 stroke.

Is that current pricing?

Call or google them to find out

Looks like yes. A Ford Performance 460X block at Summit is $3300 as well, there are multiple BBF cast iron options at the $3k-ish price point.

There is no reason a Callies MP cast iron block is $6500 (hey, it's on sale this week for $6000 at Mancini's!).

Looks bad ass! I don't know anything about the intake manifolds but if you think what you have will hold it back, maybe send it to John Marcella? I've not needed his services so can't speak from experience but his work from photos looks truly amazing.

Wise choice!

I've been having a bit of a discussion back and forth with Kaase's shop about the valve springs. The net cam lift is around 0.780 (gross lift of 0.800 with 0.020 lash) but the valve springs they supplied with the heads are rated at 0.730 lift. (Manley 221443)
The guy at Kaase's shop tells me that they run those springs with that cam but I have my doubts. I hate to doubt anything that Kaase says but the math doesn't seem to quite work out right. We're going to mock up the head again and double check everything. The Manley springs are expensive so I hate to have them go to waste. A high quality spring + retainer + locks combo goes for about $1000 these days. Prices have basically doubled in just a few years on some of these parts.

Sounds like the wrong spring for a 0.800" lift cam. 1.950" install height and 1.170" coil bind is only 0.780" lift? Do they want them installed at a higher install height like 2.00"?
I wouldn't think so as 235 seat pressure @1.950", and 535 lb/in rate seem fairly low pressures for such a large cam?

I watch way too much youtube, but Mike Finnegan had John Kaase rebuild the Hemi in his '55 Chevy and he did not have good luck with them at all. Some of that could've been Kaase not being familiar with hemis though.

What installed height are the springs set up at?

What’s the available installed height?

Is the vehicle the engine is going in destined for some street duty?

Personally, I don’t see a set of Manley 221443’s being the hot set up for nearly .800 lift with typical BB valvetrain weight components………. Unless the cam uses very tame ramps, and can function properly with whatever spring force you’d end up with by installing them at 1.250”+ net lift.

There are several more spring choices that facilitate .800-ish lift if you can get the IH closer to 2.00”.

Installed height right now is 1.950 and there is a lot of room between the retainer and the rocker arm. So I can easily go 2.000 or 2.050 installed height with a different spring and retainer combo. I'll end up doing that if I have to but I'd rather not throw another $1000 at the engine before I double check everything. It just seems to be a weird conversation with Kaase. They tell me that is the spring they use with that cam (and they sell a lot of these combinations) but it is not the right spring to use with that cam according to Manley. Maybe Manley has bad info printed in their catalog but that seems odd too.

I did have this issue before with dual conical springs from Comp. They told me to use the dual conicals for a solid roller cam but the catalog says they are only 150 on the seat. We went ahead and got the dual conical springs and they measured 200 on the seat, plenty on the nose and the coil bind was just right. So the guy was right, the catalog was wrong and the springs worked great in that engine.

This is a dyno test engine for now. We'll get it sorted out on the dyno and then put it up for sale next spring. Hoping to make around 900 hp at 7000 before we're finished with it.