Ok guys time to pull the motor! Got a few choices and I'm lost lol! I could always just do a rotating assembly on my stock motor and the turn up the boost... Or... I talked to this guy from a mod shop... He suggest getting out of my stock 281 alum block and go with the ford 304??? Bore it up to a 324 stroker??? And it would be rock solid and take any thing I throw at it... I don't know I've never heard of this but he made it sound real good... Help??? Thanks

 

Its the cast iron big bore block from Ford using a stroker crank.

http://www.fordracingparts.com/parts...tKeyField=9778

Not a bad way to go IMO if you dont mind the extra weight of the iron block. Its nearly the capacity of a 5.4 in slightly lighter trim with the added bonus of being able to use all the important 4.6 (intake, headers, et al) stuff.

Ford's top end kit (cnc heads, hot rod cams, racing intake) makes 400+ hp (430 hp IIRC) on the 4.6 N/A with a tune and headers on the dyno, all things being equal, that'd be roughly an extra 41 hp with the 5.3, not a bad way to go IMO - no replacement for displacement when your talking N/A

If drag racing is your game then iron blocked 5.3 wont really be much of a hassel, if you like the curvy stuff then you'll notice the difference as the car doesn't seem as flickable (is that even a word ) Handling wont totally go to hell since the same year GT500 can out handle the same year GT (stock for stock) and the 5.4 in the GT500 uses the heavier truck block with DOHC heads and all the supercharger gear to put it in perspective and provided your willing to mod the suspension.

You can get more esoteric than this if you care to but all thats largely academic and a big can of worms other than to say maybe it might be worth looking into a set of custom cams since the 5.3 stroker by dint of its altered rod/stroke ratio probably wont make the best power on a set of cams designed for a 4.6 (then again a company like Comp Cams does only offer a single set of bump sticks to fit both the 4.6 and 5.4 so it probably isn't that bad).

 

Will I have to bore that any? To make it a 324? Sorry this stuff is kinda over my head... Wanna know what I'm paying for...

 

Yeah a 324 is .010 over the standard bore in the CI 5.0 block (3.700)

Check and make sure the block has an oil system that is compatible with the 3v's cam phasers (requires the correct oil passage) so you can maintain functionality or else the cams will have to be locked out.

 

What would you suggest? Block wise?

 

Way easier just to stick with the 3V block. It's one of, if not the best/strongest block Ford makes. A few more cubic inches isn't worth the hassle.

 

Question: if all other things were equal (incl displacement), does a longer stroke change the power curve? As in more low end tq or less? Or more high end hp or less?

 

I think the CI 5.0 is a good place to start provided it can accomodate all of the stock 3v stuff. Converting a standard 4.6 block over might get pricey if you have to sleeve the block for the added displacement (especially something like wet sleeves).


Two identical engines in displacement except for the bore and stroke will be pretty similar in output. Thats provided the heads flow the same, the rod/stroke ratio is the same, ect, ect, ect.

When your talking modifying an engine like whats being discussed here and using components that aren't ideally setup for thier respective engines then thats when you see things like a 5.3L 3v based on a 4.6 producing different torque curves.

 

OK, since its less then ideal, but nevertheless sort of practical in terms of affordable upgrade, same question.
How does the longer stroke affect tq & hp, vs a standard (or shorter) stroke of the stock 4.6L (if the displacement were the same)? See what I'm asking?

 

Longer stroke engines with less than ideal rod/stroke ratios tend to peak earlier than a comparable short stroke engine with a better rod/stroke ratio.

When you stroke an engine and the bore remains the same, piston speed is higher so the engine develops more suction, the longer stroke engine will also probably be valve and port limited - less than ideal valve sizes for the displcement and port dimensions & volume that dont support high speed operation, all of which make it seem like a longer stroke engine peaks earlier and produces more torque.

Something alot of people dont realize, if you have two engines of the same displacement but utilizing different bore and stroke combinations - yes, a longer stroke creates greater mechanical advantage, but a shorter stroke engine uses a piston with greater surface area for the combusting charge to act on - hence my statement given ideally engineered engines, both engines will produce similar power and torque.

I dont think the 3v engines really suffer from a port volume issue, they might still be valve limited (but probably not), the 2v engines defintely suffer from this in a stroked application and 4v engines obviously have no problem at all.

The CI 5.0 Ford offers also has the added benefit of being a larger bore engine relative to the standard 4.6 - this benefits airflow since it unshrouds the valves allowing the same head to flow more air

 

Good stuff here. Thank-you

 

The engine in the Saleen Panelli Jones Mustang is a 3V 4.6 stroked to 5.0; it's rated at about 400hp.

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