quote:Originally posted by PanteraDoug: Didn't Kelly Coffield in a previous post, say that in addition to the A331-A3 intake, he had one that fit the as cast B302 heads (like George's small port) plus one that fit the B351 heads but wasn't sure if that one (for the B351 heads) if that was just a small port opened up to match the B351's? Should we just call those A331-A3, A331-B351, A331-C302?.....Kelly?
Yes, that's correct. I’ve seen a couple of the small port A331s and still have the one mentioned earlier. If I had to hazard guess, I’d say when that intake was tooled, they built one set of core box tooling that made the A3 size ports and runners. The small port versions were probably made by hand filing and sanding the larger core to the smaller runner size at the request of someone(s) Ford was willing to oblige. Castings were massaged like this for customs frequently.
quote:C3s aren't an option for me because they lose the Cleveland valve cant and require an expensive shaft mount rocker setup. I don't plan to ever pull the revs to justify such an expenditure.
Be advised, there were two heads made by Ford that carried the C3 designation. The more recent ones pictured above do have different valve geometry and valve train components but the earlier ones are from the same era as the A & B series heads and use the same 335 series components as the Ford high port and the Clevelands. There were three heads in the early C series; C3, C302, C302B. C3s and C302s were very similar as were C302B, but C302B had a number of improvements such as thicker decks, more meat in critical areas to allow more porting freedom, the valve cover rails were raised about ¼”, and the one oddball head bolt boss that was shorter than the rest was raised so it was the same height as the rest allowing the use of all the same length head bolts/studs. This is typically the easiest way to spot a C302B with the valve cover still in place.
However, as all things Ford, there are exceptions as I have seen one set of earlier heads with the taller head bolt boss. For A3s, there were two different exhaust flange patterns too.
quote:Originally posted by Looftie: I obviously have a lot to learn about these old school speed parts. Until a month ago, I didn't even know these aluminum heads existed. I still want to learn more about the B3s, which seem to be even less common.
B3s are the same head with an intermediate runner volume and cross section between the A3 and C3 series. The problem with these heads are they have usually been through so many hands and so fiddled with, you just don’t know what you’re getting unless you closely examine them. Occassionally, you find real gems that have been masterfully worked.
Justin, I’m not sure what the goals are for your build and if your response to my previous post about how your car is set up ever makes it to the board, I’ll comment further if you like, but A3s are actually a pretty good choice for a boosted engine not only because of the intake port side but also because the raised exhaust port performs much better and will be able to keep up with and support the additional power much better than 4V Cleveland. However, I think you should forget about them for your Cougar or any other shock tower for that matter, because with 9.2 deck and higher the ports are so much higher on these heads, there isn’t room to make any sensible exit turn before they hit the shock tower and this will negate the benefit and crap on the performance of the affected primaries. So unless you are going to cut out your shock towers and put a coil over kit in there, I’d suggest you forget it.
It’s not always a popular view but IMO, with the exception of combustion chamber design, in the 30 years since the old FMS high port heads there really hasn’t been anything new introduced by all the companies offering aftermarket that still have 335 series valve geometry….it’s all just marketing. This doesn’t not apply to the newer(est) variants with different valve geometry which certainly does matter but really only for people that are competing in professional ranks, not for guys with pump gas engines in street cars, even boosted ones. It’s about proper selection/combination of parts and who is building and working the parts. All other things equal, all the aftermarket heads won’t better (or IMO even match, due to the exhaust port) the performance potential of the old high port heads but you have to be in a power range that it matters and they have to fit your engine compartment. Panteras are a blessing in accommodating them but not shock tower street cars.
I also get a chuckle out the aftermarket heads guys complaining about their heads being copied in China when they in fact are just do the same of the original Ford design.
Now, valve train components such as cam, lifters, springs, valves have gotten better allowing reliable combinations not previously possible.
Adding a turbo, intercooler and waste gate, oil management, engine control, sensors, etc is a lot of additional overhead and complexity. Just me, but I wouldn’t add boost unless it was to achieve >800HP, but I wouldn’t throw that at a stock Cleveland block nor rods. I say this because 550HP hydraulic roller 408CI stroker Clevelands with sufficient street manners (even parked behind and automatic) are common now and engine builder you mentioned to me is knocking on the door of 600HP with his builds. I’m North of that but have a solid cam.
Even though >1000HP boosted street engines are becoming common, it’s a ball rolling down hill and even with engine and drive train components to handle the power, detonation control will require a departure from pump gas.
When you mentioned a mild boosted build, what difference does you head choice make when cam selection or a few psi of boost have more influence on result. What are the goals of your build?
Best,
Kelly