Unconventional Street BBC head.

[Fatman]

I few years ago I read a mag story about a BBC head that was being developed to run high compression on the street. From what I remember it was a conventional port layout, reduced valve angle (possibly very shallow like around 5-10 deg), small figure 8 shaped chamber with lots of quench, small valves (something like 1.85 in and 1.5 ex) centrally located spark plug.

Can anybody remember this and possibly tell me were to get more information or know what happened to that project.

I could be wrong on any of the above details but it may jog someones memory.

[beth]

I remember seeing that. They were designed by Jim Fueling. If I remember right they had 11 to one comp and were low speed for towing etc.

PS I found this on google but it was posted 6 years ago,

Klein Engines, in Phoenix, is the authorized vendor for Fueling Centerfire heads.


beth

[SchmidtMotorWorks]

I saw the patterns for them at the foundry I use about 7 years ago.
I guess they were probably sold in the feuling auction a few years ago.

If I remember there was also a three valv ehead. looked like a mess to me.

[MileHighMan]

I saw those heads at the lake about 8 or 10 years ago. If I remember right, they were 4-valve heads. It ran very good! Good Luck.

[Fatman]

http://www.454ss.com/gallery/JimD/Jim_D.htm

Thanks

Found what i saw here if you want to check them out.

Why hasn't any of the major manufacturers produced anything like this. suited to low rpm pump gas motors. is there no real benefit over conventional 24-26 degree BBC heads.

Or maybe something in the middle of the feuling design and a conventional design. shallow valve angle but move the spark plug out from between the valves to allow a bit more valve for either higher rpm or bigger motors.

Surely there'd be enough market to support it.

[beth]

My thought is they are ideal for the purpose they were designed, low speed and towing. The marketing problem is, at this time factory towing motors are much more efficient then they were 10 years ago and much harder (and illegal) to modify successfully. Expensive motor coaches and heavy towing applications mostly use much improved diesel now.


For performance, the centrally located plug makes valve sizes restricted. I don't understand why designers are not taking advantage of the excellent smaller spark plugs available now. The valves could be brought together some and valve sizes increased. It could be made efficient on a 396/427 I would think. Even those are rare these days.

beth

[Stevespeed]

Had some dyno info from Feuling on a reasonably big (I think it was around 560 inches) dyno mule. It was on an old computer, don't know if I still have it. It made incredible torque (if I remember correctly it was around 700 lb. ft.) at an incredibly low rpm ( like 2600 rpm). Basically duplicated the performance of a modern turbo diesel. Last I seen there was a whole pallet full of unmachined castings at Feulings but that was before they closed the doors and don't know where they ended up.

[Fatman]

My thought is they are ideal for the purpose they were designed, low speed and towing. The marketing problem is, at this time factory towing motors are much more efficient then they were 10 years ago and much harder (and illegal) to modify successfully. Expensive motor coaches and heavy towing applications mostly use much improved diesel now.


For performance, the centrally located plug makes valve sizes restricted. I don't understand why designers are not taking advantage of the excellent smaller spark plugs available now. The valves could be brought together some and valve sizes increased. It could be made efficient on a 396/427 I would think. Even those are rare these days.

beth

I was thinking more along the lines of a series of street performance heads.

What about a cylinder head that is designed to work efficiently with todays pump gas. The aim would be a high performance head that would be more tolerant of pump gas octane, quality etc than a conventional port and chamber design. Are there gains to be made over conventional style BBC heads?

Are there benefits to be had in reducing valve angles and having a tighter chamber with lots of quench area? Not to the degree of the feuling head but still much more than a standard 24-26 deg head.

Would this work well? just some thoughts
A 5 or 10 deg valve angle, 2.1 x 1.6" valves, a tight chamber but not as tight as the fueling head, move the plug out from between the valves to allow the larger valves. Would probably need a different port design to work with the valve angle, chamber shape and standard port location but there should be enough room given the aim is for moderate rpm and a big port shouldn't be be needed.

You could up the valve and port size to suit bigger motors.

Would this be a worthwhile cylinder head?

[beth]

You need shallow valve angles to increase squish and to spread the squish around the chamber rather than have it offset. Shallow valve angles require raised ports, different intake, raised valve train etc. It all becomes a trade off. It's like trying to make a 20 year old car look like a new one, styling is easy but the engine position, seating position, wheelbase, track etc do not fit.

If I were designing a head for anything, getting the plug as close to center would be the first step. I think you can look around and see those that are doing this fairly easily from the outside, lotsa hard runners.

[Fatman]

the idea would be to allow the use of common intake manifolds by not having a raised port location. I know it's not ideal but not chasing all out performance. I guess it would depend on if you could get good intake charge quality with an acceptable amount of airflow.

the relatively small valves would still allow a a plug close to the center. Not smack in the middle like the Feuling head but still closer to the middle than a conventional head. The smaller the valves and the more you were willing to shroud the valves on the cylinder walls, the closer you could get the plug to the middle.

The main questions are: Can it be done? and Would there be benefits over a conventional port and chamber design?

[SchmidtMotorWorks]

Beth... I don't understand why designers are not taking advantage of the excellent smaller spark plugs available now.

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I have been looking for a good small plug, can you suggest one?

[C Stevens]

RE: the Feuling 3 valve heads, Patents anl liscensing were sold/ assigned to FORD. I'd loved to have been a fly on the wall when Mercedes thought they could steamroller Jim, and found out they were up against FORD.

[beth]

Beth... I don't understand why designers are not taking advantage of the excellent smaller spark plugs available now.

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I have been looking for a good small plug, can you suggest one?

I don't know your requirements. Ngk makes 8mm, 10mm and 12mm in different reaches, materials, heat ranges and styles. Look in an NGK catalog or look at this,

http://s110.photobucket.com/albums/n108 ... h=imgAnch1

I have used 10 and 12mm, don't have experience with 8mm

beth

[SchmidtMotorWorks]

I have been looking for small plugs to make space for water in a 4 valve head. I wonder if any of those small plugs have heat ranges that would work in a high performance engine?

[beth]

Yes they are used exclusively in high performance motorcycle 4 valve engines. They come conventional or fine wire platinum, surface gap and Iridium, racing engines seem to run in the 7 to 9 heat range. seems like 10mm with 3/4 inch reach would work nice.


Take a trip to a local motorcycle supply and ask to look at a variety of ngk plugs, then consult the ngk catalog.