We work on many engines for folks who actually race them competitively, where every little bit counts.  My dyno headers are made to (a) fit and clear the cart or stand on any dyno I may visit, and (b) share the same step lengths, sizes, and collectors that will be used in the vehicles in which the engines get raced.  When we dyno engines other than race-only engines, it probably helps the numbers, but they are in fact numbers generated by THAT engine.  Generally speaking, most engines will need two or three less jet numbers when run through a full exhaust than the best tune when run "open headers" on a dyno.  Most of my race engines come right off the dyno, go right in the race car, and require no additional tuning, so the dyno headers are very representative of the step headers we use in the cars.  For me, it is about repeatability and accurate tuning in an environment that is as close to the real situation as possible for the racing engines.  Numbers don't mean as much as the ET slip.  Using dyno headers has never produced any ill effects for street engine customers.  Lately, we have done more and more work with custom headers and collectors for the street/strip crowd.  You can tell the difference in good header design by the butt-o-meter too, you don't have to have a race car to feel the benefits. 

When scavenging is very efficient, it will require a richer mixture on the intake side.  Better exhaust means less garbage is burped back into the cylinder and the intake manifold at overlap.  More power will require more fuel.........physics.  I have never seen a header or a collector pick up power that didn't show to be leaner in an A-B test, and when it is fattened up..........a little more power comes with it.  When whatever you hang on it for exhaust hurts power, it has always richened it in the process on everything I have tested.

I still have this engine for sale....PRICE REDUCED...$19,500 ready to ship.  Also have a 1x4 just like it with a BBM block and Ed RPM manifold, 850 QF carb at $18,500.  Need to run the single four engine, but waiting for someone to want it first..............I found a set of cast BT pentroofs that can go on the first one that leaves......the other gets engraved fabbed sheetmetal covers, or something of your choice that is AVAILABLE.  Valve covers seem to be a problem right now...........

I think it would do well.  I have that cam in the shop 1-ton.  It has power steering and power brakes.....vacuum is great.....it is a straight shift, however.  It would be just peachy for the A/C with two things:  (1) a '70's era adjustable solenoid hooked to the hot wire for the compressor clutch........I think Holley sells one that mounts nicely on the baseplate, and (2) about 500 rpm more slip than a bone stock converter.  I have put this cam in 445's for pick-up trucks with C6 and used a stock converter, but both times they had 3.70-ish gears.  I think the car could benefit from a touch looser converter and then you could run highway gears if desired.  Might also put it on a 114 sep and smooth it up a little more.  Would hurt the power just a bit, but would be smoother in a cruiser.  I don't think an Ed head without mods would be as good as the N heads the way we did  them.  The BBM would like the wide lobe sep better than the stock head, and require less timing, but might not perform any better in this combo.  The small cam and short duration might not get the good out of the BBMs.  Some BP Pro Ports would be better than all other options, but really overkill and an expensive addition for not much gain in this situation.  Below are some numbers from the dyno.

RPM          TQ          HP

3900       467        347
4000       470        358
4100       470        367
4200       470        376
4300       461        377
4400       463        388
4500       462        395
4600       454        398
4700       452        405
4800       450        411
4900       445        415
5000       443        422
5100       439        426
5200       430.7     426.4
5300       421.4     425.2
5400       415        427
5500       401        420
5600       399        425
5700       381        413
5800       377        416


40 degrees total timing, high 12's A/F, 185 degree water

Stuska dyno with D-Pac data aquisition.  This dyno showed me 626 hp on one of my EMC junkers and the contest dyno showed me 640 hp on the same engine.  This dyno also showed me the same power as Jay's dyno on a Tunnel Port I worked on, so the numbers are legit, if not a little conservative.

Very doable.  I would not put those valves in a LR head.  The valves will be very close together with that valve spacing, giving potential to leaking where the valves almost touch.  Also, the 2.19 intakes make it VERY thin near the spark plug, and make a future crack there more likely.  I would suggest some towers (with venting) to make some oil stand in the lifter valley to help lube the lifters, or preferably drill the block for oil and use HIPPO Crower lifters.  Lifter life is shorter without pressure fed oiling.

Phooey!!  Too much carb can look great on a dyno and not accelerate near as well in a car.........especially a heavy car.  Carb spacers are the same way.  Sometimes you can keep stacking spacer on one and keep seeing dyno power go up.....only to hurt the ET slip later.  Rather than say the biggest carb is always better, I would say that SOMETIMES a bigger carb is better, depending on the carbs in question.  I seem to remember a certain 4150 carb that tested better than a Dominator on Jay's test engine...........but got excluded from the final decision, LOL.

The Dove end supports are a step in the right direction.  They are only 5/16 bolts, but still the right direction.  I have often considered using a bottom plate, like the HS pictured, and a countersunk 7/16 under the shaft for mounting.  Also thought of larger shafts like that, with a .125 through hole for oil.  Lots of ways to approach it.  The main problem is the 3/8 bolts....and only four, are not enough for serious roller cam  spring loads.  The T&D has eight 7/16 holding the stand.  I have had a total of two Dove super HD units....both somewhat mangled and stuffed in a box here someplace.

The single shaft T&D is not compatible with stock-size stuff.  The Dove end support will only engage an extra length Dove shaft.  He should not have put two sets of oil holes in those otherwise OK shafts. 

I like the single shaft T&D for high lift flat tappet or hydraulic rollers.  I lean more toward a bushed non adjustable with heavy shafts, studs, and end supports for streetable hydraulic rollers.  That works very well up to 400-425 open, with no bearings, no adjusters, and no roller tip to fail.  Good for 2-300 more rpm than aftermarket stuff that has more inertia weight.

I have ten BBM blocks that are not spoken for at this time. Prefer to sell them in engine jobs, but would consider selling a fully machined and prepped block.  Just info...not an ad.

I tested the 4500 manifold and the single plane 2x4 on the same engine.  Power was just about the same.  The 2x4 was just a little better peak and the single carb had a little more low end torque.  They were so close you would never know it in a street car.