Jack Roush Race Engine

$10,000 would be more like it IF it is fresh but these things are usually somewhat negotiable?

On race engines often there has been damage that has been repaired. That is significant also.

It depends on other specs on the engine as well such as the type of roller rocker arms. The type of valves such as are the titanium and even if they are, what type, coated stems or not coated.

Depends too on where the bearings are at now? Most racers do not want a crank cut under .020. They feel that the bearings themselves are too soft at .030 under. There is more bearing material in them at that number which is not as hard as the crank material itself and will compress under load.

I have little opinion on that.

The block and the heads are the major attraction. It's difficult to put a dollar value on either. It is really what someone is willing to pay for them or stated differently, how much someone wants them?

FYI, the link to the ad does not work for me. It just brings me to the front page of the magazine.

Thanks for your thoughts on the motor. I realized the block and heads are the most valuable. With all the technology put into some recent manufacturing developments do you think these heads would still hold their own against today's modern Cleveland heads or are today's offerings cheaper and better?

quote:

FYI, the link to the ad does not work for me. It just brings me to the front page of the magazine.

I realize now you can not find the ad through their website I found it the old school way in their Print Magazine in the October addition. If you want any other info let me know. It's kind of a neat little magazine that currently even has a few factory mopar race cars listed for sale

Personally? Yes.

Two things that I noticed. Some of the Australian aluminum heads as of recent strongly resemble the ports on the A3 heads.

With a nice 3 angle "valve job" they flow 330 cfm at .600" of lift. You can extrapolate that almost proportionally with that head to about .800" lift.

If you are a racer attempting to milk every last drop of horsepower out of the heads and if you found a head better, it wouldn't be drastically better.

It's a good head.

That entire series of heads, the A3, the B351, the C302, the D and all of the improved castings that follow them are highly sought after.

The A3's tend to be better for larger than 5.7 liter engines.

All of the engine builders will tell you that in "their" experiences one is better than the other BUT there isn't one of them that will turn down a set of A3's unless they were seriously hurt, and the nature of the repair would be questionable for the durability of the thing?

Which one is better is just an academic debate and SOMETIMES the term better needs to be defined or qualified first?


The block you can't know until you disassemble the engine and examine it. Some of those blocks had core shift and some show about .100" OR LESS at STOCK bore dimensions on the thrust part of the cylinder bore.

Even still you could probably sell it in the $4000 range without the buyer even coming to look at it. Simply put. It's a very desirable block.


What would be nice with this engine is that it wouldn't take much at all to detune it a bit for a street car. Probably just put a civilized camshaft in it?

I personally would not run titanium valves on the street but there are those that are doing it.

Excellent info, once again and getting to what I was figuring. I am a relatively young Pantera owner being born 6 years after my 74 and am not as knowledgeable about the Motorsport heads. I did however grow up in a family that dealt mostly with FE's and chasing expensive 427 parts and now (even before the Cleveland) the modern aftermarket has came around producing great products with modern technology for those too. The question that often comes up then is do you pay a premium for vintage parts such as medium riser heads, when the majority of cars you are dealing with such as Mustangs never had a factory 427 anyways? Or do you buy a modern Survival Motorsport, Edel, Blue Thunder etc...? I know many will pay more to have a Ford oval stamped on parts (I know I often do). I believe that some of these things will be coming up when dealing with 351C vintage performance parts such as listed. Like you said many of the Australian heads are similar or at least comparable in performance and price wise possibly cheaper (or not depending). Lastly with more promises of a modern Cleveland block coming into production paying for a vintage block and then having to get it checked out may not make sense either.
Regardless of all this though I still think there will be many that take pride in chasing and acquiring vintage parts especially with a Ford oval stamped on it. I will go as far to say imo that with the recent increase in value of our cars (especially stock ones) that Ford parts regardless if they are over the counter performance parts or not will hold value more than other aftermarket parts.

There are at least four schools of thought I have recognized here and in the field on Panteras.

1) modify everything to the owners personal desire with no consideration of what the car is or was

2) upgrade the car to what the owners interpretation of what the car would be now if it was currently produced

3) make the car a "day 2" car. Modify it to what it would have been "in the day" just after the car was delivered new

4) stock. No mods. Original air in the tires if you can get some.

I'm kind of a day 2 guy with a little leeway towards making the car more dependable with best technology available now.

"Ready to Assemble" to me means this is not an engine, it is a box of parts.

If it were an assembled and running engine, AND there was documentation that it was "recently" assembled by Roush's shop, i.e. a new or refreshed engine, it "may" be worth the asking price.

Since it is a box of parts, it is worth no more than the sum value of the parts, which I can guarantee you is far below $15K Canadian. This is a box of used racing parts, refurbished at best. If the parts are truly parts that were once used in a fully assembled Roush engine, each part will be identified (engraved) as such.

If this was once a Roush engine I can guarantee you the connecting rods were not originally part of that engine. They stick-out like a sore thumb, they're out-of-place. The reciprocating parts look mostly like stuff from the 1980s, except the Probe connecting rods. Its an old school crank, old school crank damper, old school pistons. I'd expect to see old school name rods too like BRC, Crower, Carrillo. Was the original set of rods ruined?

Is the crank an expensive, US made, fully counter weighted forged or billet crank, or a lesser crank? I Googled XH10089 cranks and seemed to see the same picture of the same crankshaft every place I looked. Like that same crank has been bouncing around the internet. Is there a problem with it? Or is this crank a different one?

Is the Australian racing block a "real" Ford SVO version with uniformly thick cylinder walls, or is it a block pulled from an Australian automobile and 4 bolt caps added? The difference is the amount of core shift ... the cylinder walls were too thin in places for Ford SVO, so the block remained in Australia and was used as a 2-bolt production engine. The only way to know is if the wall thickness of all 8 cylinder walls has been sonic checked. SVO blocks will have walls thicker than 0.200" everywhere, even after they've been bored. So is that sonic check report available?

Notice the part about "Aussie block with stud girdle". Since when does any Cleveland block require a main bearing cap girdle in a naturally aspirated application?

"Freshened" A3 heads are "used" heads, which have hopefully had a valve job and new guides. What's the valve recession look like? It can be pretty bad with A3 heads. Valve recession (the sharp edge around the valve seat) is a flow killer.

Since you're familiar with the FE engine, I'll explain the A3 head this way. The iron 4V head was a racing head with a high port, as high as production limits allowed. Similar to the FE medium riser head. Both heads have the same ramp in the floor of the intake port, which improves flow; the ramp gives the head the flow of a head with a higher port. In the case of the medium riser FE head, it performed as well as the high riser FE head, but allowed the induction system to fit below the hood of production cars; NASCAR had banned the use of high riser heads for the 1964 season because Chrysler had complained that an engine with high riser heads didn't fit below the hood of a production car unless a "bubble" was installed.

During the 1970s racers discovered the ramp in the floor of the 4V port was throwing fuel out of suspension at ultra high rpm (above 8000 rpm), therefore a few horsepower could be picked-up by eliminating the ramp, grinding the roof of the port to make it as high as possible, and opening-up the port beyond the ramp to give the port a more consistent shape and cross-sectional area. They ended-up with a port of about the same volume they began with, in the range of 250cc when the valve pocket is opened-up.

The A3 head was the first aluminum racing head for the 351C. NASCAR rules limiting induction system height had been lifted, mostly because all teams were using the new high rise single plane spider type intake manifolds. Therefore the ramp was removed from the floor of the A3 intake port for the reasons explained above. The port was raised a small amount, about 1/8", to increase air flow and compensate for removal of the ramp. Removing the ramp from the port floor raised the floor, thus making the port opening smaller, but the port volume is about the same as the iron 4V port (240cc before either is ported), they are tuned for similar rpm.

If by modern heads you were thinking of products from Trick Flow and Edelbrock, well that's kinda apples and oranges. The 4V head, the A3 head, and all subsequent Ford SVO heads were high port racing heads which flow very well with high lift camshafts opening the valves 0.700" off their seats or higher. In terms of street performance, where the valves aren't opened more than 0.600" the CNC Trick Flow heads acquit themselves well, considering they are a 2V (low port) head.

The A3 heads have the lowest intake port of any of the aluminum SVO racing heads, and it lacks the high swirl combustion chamber topology of the Yates heads and later heads. The cool thing about the A3 heads, the port location and port dimensions should allow the SCM intake manifolds to bolt-up, so you have some manifold choices with good availability, although expensive by the time they're shipped to north America.

Excellent info, George. I would love to have a set of Scott Cook heads and intake, and Doug I would probably choose the stock looking ones to to keep things vintage looking but benefit from the modem technology.
As a side note with recent changes in world economies I would think some enthusiasts from the US should look seriously at the Aussie speed shops since the currency conversion is starting to look quite favorable for the US. Unfortunately being from North of the border my currency is on a similair slide with Australia. Hopefully in the future I can holiday there and somehow stuff my luggage with a set of heads and intake.

With the available parts it is hard to make a big mistake.
If I was racing I would have taken a different approach.
For one thing I wouldn't be worried about the leather interior, a good stereo and Weber carbs really look nice in displays.
I limit my Walter Mittyisms to period stuff and a simple 550hp.

To add to George's post, there are two different 'stud girdle sets'. One supports the main bearing 'studs' while the other supports the rocker arm studs. I run the second type-(Ridgeway)- on my A-3s for insurance against breaking valve springs. They are a 3-bar type that fits under most aluminum rocker covers with a minor bolt-swap. Ridgeways are no longer available, but there are copies around from Jo-Mar. Note- the 'Grand National' size will NOT fit under most rocker covers!