Technical Dynamic compression...will this work?

Going on that theory, why don't you just drive a 65-73 Mustang, Fairlane compact or simply put a flathead in your shoebox???
The Irony here is you are considering using GT40P heads of an Explorer [or '93 Cobra]

Suit yourself, but I can assure you that it is a shitload easier to buy a late model engine from a U-pull and swap dizzy ,manifold, carb and re-cam it. [you can even swap rocker covers, oilpan etc to make it look old]

This could all be completed in less time than it takes a machinist to get around to "de-ridging" a 50+ year old motor for a ring & bearing job.
Any flat tappet cam swap you make will also require the extra cost of lifters etc [Then you need to add zinc additive to your oil]

One thing I've learnt as I passed 50........."I'm running out of things to learn the hard way"

 

So, just so we know what we're talking about here, this is the 289 I'm thinking about starting with.


Definitely needs cleaning up, but I don't feel like it's in any worse shape than a junkyard motor would be.

 

You know the first thing if you walk into an engine builder (or building your self) is how much
do you want to spend. You can get 300Hp rebuilt 302 roller long block pretty reasonable, warranty and all. Or you can acquire a 289 block, sonic test it and if more than .100" walls have the rest of machine work done. 289's are extremely thin walled let alone core shifts and corrosion. Then you can start another process with the cylinder heads. The valve train is a whole other w/ PV clearance and rocker geometry. Unless you are building a race specific motor, you will likely spend twice what a crate assy cost.

 

Sure, I could go the 1-800-HOT-ROD route and put a crate engine in it. But then I wouldn't have the ability to say I did it myself, all I'd have in it was the checkbook. I wouldn't learn anything either. If it's that much better to put in a crate engine, and order everything from a catalog and use all modern parts, then why does this site even exist?

 

If your starting out right from scratch why not use a 351 Windsor? They made few million of them, so there plentiful, cheap and well supported in the aftermarket. Besides, 99% of the people that look under the hood couldn't tell the difference between a 289-302 or 351 anyway.

 

351's don't fit well in a shoebox Ford - the extra deck height causes interference issues with the steering column, if I remember correctly.

 

Sounds like your decision is made then. 289's are great little engines, Iv'e had a dozen of them over the 45 years of my driving life.

 

Aren't all small-block Fords with 4-inch bores thin-wall castings? Or are the 289's thinner than the later 302's or 5.0 HO's?

 

Later model 5.0HO's and all roller blocks are thinner wall. The Ford engine lost 5lb in the block casting alone.
The downside to these engines.......After about 550HP [too much boost, juice, or RPMs] and they will try and multiply into 2 x 4 cyl blocks. [7200rpm is the limit]



But these were cast from harder materials, so they barely wear out.

I have pulled junkyard engines with over 200,000kms [120k miles] that still have the crosshatch in the bores. Most I've pulled never needed opening up because they compression tests were OK
You can re-ring them easily without honing the bore [ just use "protec" rings]

If you find and '86 to '91 HO engine. These came from the factory with TRW forged piston [Black oilpan] After '91 the HO had Hypereutectic pistons [Grey oilpan]

They are not the "King of all engines", but are modernised enough not to provide any grief yet can still be passed off as "nostalgic"
The machining costs of a re-bore alone is about $300 plus pistons and re-balance! You can buy a 5.0 for that and would have to be damn unlucky to get one that needs a re-bore.[you could probably buy a 2nd engine and still not exceed the above costs combined]

 

My main assumption through this process has been that any used motor I get would need about the same amount of machine work, so I might as well start with the cheapest short-block I can find. Hence the 289, hence the original questions. I've been quoted $150 for hot tank, magnaflux, hone and new cam bearings, so that brings my total cost to $200. If there's a good chance the Explorer engine will not need that level of work, and still come with all the nickel-and-dime parts I'll need anyways, that may be the better option. I also didn't know about the material difference. Sounds like I need to go junkyard diving.

 

At the power level your shooting for and intended use (mild street performance and automatic) on a budget any 289/302/5.0 SBF short block you find will be fine. Get the one that is in the best shape you can find. Be sure to match up flexplate and damper to the same vintage as the rotating assembly.
Later 5.0 motors are fine and offer the benefits of a roller cam...use early front dress and accessory drive and only the more observant sbf folks will spot the later block hidden below.
If you're budget is super tight the better deal long term may be to find a complete good running CrownVic, Merc or Mustang with an AOD. The Mercury would likely be owned by older folks...better maintained and abused less...swap a Stealth intake, conventional dizzy and carb on it with headers and do some cheap reliable cruising. Part out the carcass to off set the purchase. I'm thinking there has to be good running 5.0 Grand Marques out there for 500 bucks...which is cheaper than doing machine work and trans rebuilds on vintage stuff.
....just a thought.

Sent from my SM-G950U using The H.A.M.B. mobile app

 

For .5 point of compression, just use the parts you have, degree the intake centerline 6-8 degrees advanced (make sure you have adequate piston to valve clearance), and let it eat.

 

The more I think about it, the more I'm leaning toward just going for a complete later motor. That way I at least have a complete engine, instead of having to nickel-and-dime every component. If I had the space, I would go the complete car route, but that's not really an option unfortunately. I've found a few options either way.

 

it depends on the max rpm and the %VE of the engine

for example the 418 cube engine with 90% VE (modified for racing) going to 7000rpm will flow aprox 762 cfm, take it to 8000 rpm and it needs 870 cfm
https://racingcalcs.com/cfm-cubic-feet-per-minute-calculator/

increase the VE with some head work and more flow is needed