Grizzly, i think john has designed these heads with basic improvements off the shelf to keep up with much worked G heads for the street driven cars, then if going racing you can port them etc to perform to their full potential, obviously with other bullit proof parts in the engine, race headers etc. I myself think it was a great challange to finally produce a product that can suit 2 different ends of demand! To only produce only high end racing heads, to a limited market then the costs wouldnt be worth the investment. I would think in your case with a basic street driven car (ute) that the standard new heads out of the box would be more than enough improvement in your case. I assume working out the cost of porting whatever good cast heads you could buy and the cost of the new heads would be a consideration. I allways remember Jim Broardly of  Diablo Motors sign above his door; Speed costs money! how fast do you want to go!" . regards bill.

yyy

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Aussie Bill has nailed it in that the new aluminum heads in their out of the box condition are as good as you’ll ever port a set of iron heads for maximum flow.  Where the ported iron heads typically suffer on their lowend numbers, the new aluminum heads are very stout at the bottomend of the range as well as shining in the upper rpm band.  Best of both worlds with the 'out of the box' aluminum heads.

 

As John mentions, there are no plans to put the highly ported aluminum heads on the dyno mule.  That wouldn’t give much meaningful data without a camshaft change at the very least while the bottom end of the dyno mule is definitely not 7000 rpm capable.  Both the freshly ported aluminum heads and another set of rocker stands are here so there are already plans on putting the EMC engine back on the dyno next week and getting some baseline numbers for that combination.

Lorena, Texas (South of Waco)

Bill,

Gotta love that statement, it only comes out when you've got too technical for the mechanic and it's time to walk away. Time to find a real mechanic

Looking at other ford small blocks I notice that the Cleveland flows 230cfm and 284cfm for small and large port (respectively) wasn't the large port used on a 302 Boss. For stout street performance during the muscle car era??

I think you guy's are too used to looking back at at old y performance and not looking ahead to what can be now obtained

cheers

Grizzly (Aussie Mainline)

Grizzly, not sure what to make of that ! but i think you dont realize the vast performance improvements made with many fast times and HP increases proven here by members, and their cars while keeping with the original themes and history of these engines etc. I cant help feel you are keen on the various theorys but they are not really suitable to everyday road speed driving. Hope this helps. regards bill.

yyy 

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Do ya think?

There's only one way to conclude this. Grizzly, get the new heads, have them ported, and let us know how it turns out. Even the most educated people are wrong sometimes. There's only one way to find out.


Lawrenceville, GA

Grizzly, although I've never driven one, by all accounts I've ever read the first year Boss 302's were a crap street engine. They made NO low rpm power and only ran at the top end of the RPM range. Ford downsized the intake valves and made the power more usable in the 2nd year of production.

If someone wants to duplicate the performance of a Boss 302 in a Y-Block you could max port a set of the new heads and put them on a 272 (BOSS-Y or Y-Boss ?). Now to really duplicate a Boss302 you would also need to over cam the thing to death, as the Bosses were. The cam would not run below 4500rpm even in a 351.

The factory tech in 1970 wasn't all that advanced. Ford didn't understand port velocity or chamber shape. In the 1990's there was a hugh market in the US for Australian 302 Cleveland heads because the 4bbl US Cleveland heads had too large intake ports and the 2bbl heads had a horrible, detonation prone chamber.

Making power doesn't just mean big ports, big carb, big cam. Also, street power is totally different from dragstrip power.

When I quote an engine job I give people a base price and tell them "every time you say I want the price goes up". Now if you know where to get parts for free you might be able to build a better engine at no additional cost. I have not yet figured out how to install forged pistons for the same price as cast, or how supply aftermarket rods at the same cost as re-using the originals. Last time I ordered from ARP they wanted a lot of money for their fasteners. In short, the more power and RPM you try to wring out of an engine the better the parts need to be in the engine if you want it to live. Higher RPM=Better parts=More money!

I'll bite my tongue now

http://ford-y-block.com 

20 miles east of San Diego, 20 miles north of Mexico

John, well said!

John - "The Hoosier Hurricane"

The Boss 302 was only rated at 290hp. So in reality, it was probably 320ish and the 351 was only rated at 330hp. In the January edition of hot Rod Magazine, a Boss 351 was built to factory specs and it produced somewhere around 384hp @ 6100rpm.

It is not difficult to build a Y to that level AND have favorable street characteristics. If you want Boss power levels out of your Y, it is absolutely possible - and certainly will not require that the new heads be ported.

Speed does cost money. If it didn't, I'd have a 1500 horse Y in my truck one way or another. It's not just a mechanic who doesn't want to or is not able to do the job. To really build an engine is a lot of work and a lot of time.



Other than the optional cam, the Boss cam specs don't look all that radical and seem to fall inline with the windsor performance cams. They are certainly bigger than your standard street motor.



http://home.comcast.net/~jelerath/mustang/Specs/cams-fr.html



I don't know how reliable that info is but if correct, it seems that the heads were simply the wrong choice for a street car.



Lawrenceville, GA

A friend had a Boss 302, ordered from the factory with the 4.30 (I believe). He had a 5 something ring and pinion installed before taking it home. It needed a lot of gear. As stated no low end torque.

At the same time I ordered a 70 Torino GT sports roof with the 351 C 4V. 3.00 rear axle air and so on. The Boss 302 was a 13 second car. Running off with him he could open a car length off the line, then the Torino would hold the position, passing him (after the 1/4) as he ran out of revs. The big port heads worked OK on the Torino but they were NOT economical. I never did check the mileage on this one as I knew i would not like it. I would guess 12-14 on a trip. These heads were not a good design, poor exaust ports, sewer intakes. It seemed as a different school of thought took over head design in this era,taking a turn from the smaller port design of the Y and FE. This school of thought probably was first seen in the tunnel port FE's. Understanding quality of airflow as well as quantity has taken huge steps. John has done a super job on the new heads. This is shown by the horspower, well above predictions, and fuel flow observations by Ted on the Dyno.

We need to think a 400 Hp Y that is very streetable can become common place. The short block is not the contributer to horsepower that the heads, intake, carb, and cam are.