Without getting into too much trouble with my friends and allies at Ford Racing, here's my take;
The biggest drawback of these engines is the fact that they come with a Mech. roller camshaft. Sure, people have run roller cams on the street, and are still diong so, but it's just not right for a car that has to spend a bunch of time idling, cruising between stoplingts, and just generally not operating in short-sprints like a roller cam equipped engine is intended to. A cam relies on
oil splash from the rods for lubrication and cooling, and low-speed operation combined with higher than stock valve spring pressures makes a pretty touchy situation at best. Valve spring life in these engines is less than expected as well. A solid flat-tappet or Hyd. roller is a much better choice for a street driven car.
I personally don't like the fact that they use a way-too-short 6.605" stock rod length, with a 4.300" stroke crankshaft on a 2.500" rod journal. Ford used an existing piston forging that they had boat-loads of to construct this engine with, that's one of the reasons why the price is so resonable. They had everything in overstock they needed to build a 521 c.i. engine with some slight mods. to existing parts, but in my opinion, not the right way.
I perfer the 4.300 srtoke crank with a 2.200" rod journal and a 6.800" long connecting rod combo for a big 385 series. The bearing speed on the rods is much slower, and the rod-to -stroke ratio is MUCH better with the 6.800" rod.
The engine is put together "assembly line style" which is ok, but you just can't beat a blueprinted piece from your favorite engine shop. Things like bearing clearances and piston clearances are given much more scrutiny and customized more to the individual applicaton.
The overall quality of parts used is very good, but a lack of attention to detail for the individual application is the only drawback.
Feel free to give me a call at 877-552-2112 or 586-792-6620 or mail me at
esimone@diamondracing.net
Thanks!!
Eric Simone