in terms of power, flow potential, horsepower potential, and quality the Blue Thunder heads are the better choice without a question. But they are not perfect for every build. This is gonna read a bit like an ad - I apologize - but anyone looking to make head selections can benefit from the info even if they choose to purchase from another supplier. This stuff can be duplicated locally - especially the Ed version.
The Edelbrock Stage X is essentially the head I think Edelbrock should be selling - but they repeatedly say the have no plans to do so. Of course they don't need to tell me future plans....
The heads start out as 60059 72cc bare castings. We swap out the guides to allow the use of 11/32 stem Rev stainless valves - intakes are 2.200, exhausts either 1.710 or 1.650 depending on bore size (4.070 will scratch the wall, 4.080 is darn close). We do a CNC 45 degree multi-angle valve job, and bowl blend. We detail the port opening blending back an inch or so from the gasket face. And we assemble with viton seals, a dual spring good for roughly .600 net lift flat tappet or hydraulic roller use(Edelbrock uses a single with damper), and chrome-moly hardware. The package ends up flowing in the honest 270s at peak in the .600-.700 range - and gaining 20-30 cfm at the mid-lift ranges. I've made 505HP on a 445, and 537HP on a mild 482 with these - probably nearing the end of the unported heads potential.
The Blue Thunder Stage X starts as a medium riser small bore casting. They use a similar size (2.200/1.710) but longer stem valve package. We CNC profile the combustion chamber on these, do the Newen CNC valve job, and blend. The ports on these are quite large and we leave them untouched other than blending. Assembly parts are the same as above. These heads flow mad numbers well beyind my fully CNC ported Edelbrocks - in the mid 350s at .700 lift. I've made 729HP with these on a 12:1 roller cam 482 incher after a spring/retainer swap. The downsides to the BT include wrestling with headers since the exhaust port is raised .400, the need for specialized rocker gear (either modified Erson or T&D), and the fact that the ports are BIG - making them best for larger engines and not compatable with some intakes (BT dual planes and the Victor are fairly easy to modify, OEM and Dove parts are pretty tough).
Somewhere in between these are the fully ported Edelbrocks. My stuff flows in the 320s at .700. Other folks get more from their's. Few reach the "as cast' BT flow level without major welding/rework. These actually cost considerably more than the BTs, but are an easier installation on tight engine compartments and use traditional valvetrain parts. I have made 618HP on a solid roller, pump gas 482 with these exact heads, and have reached 692HP on a heavily flogged 13:1 505 using comparable flowing hand ported heads.
Hi Barry
Your sage advice to us gearheads is Priceless!!!!!
Let us know the next car show,swap meets et all that you'll be attending so I can buy you a couple shooters/brews.
thanks again
O.B.
to achieve over 500 HP from a 397, several years ago. The dyno session was halted by the loss of bearings at the 2-6 throw during the break-in. (The best guess-timate of the reason for this destruction is that probably the dyno 'spud' included the small block pilot. It's longer than the FE and seems to force the crank forward slightly. For some reason, this causes destruction at the 2-6 instead of the thrust area.
We had only 32 degrees of timing in, and were running a pig-rich 850 dyno carb to be sure that we were going easy during break-in. The dyno told us 497 @ 7K and the engine let go at 4K coming down from that pull. Since there must have been about a second and a half between the reading and the failure, there must have already been significant drag in the engine at the time the peak readings were taken.
On the other hand, the Dove F-5s flowed about 335 at .700. They're not shelf items, and Wayne Kuchtyn, who did my porting is not now accepting work. Unless you have other connections, it's undoubtedly best to deal with Barry. He's an ace!!!!
KS
I would go with the BT's myself if I had the money
July 27 2008, 7:47 AM
Those chambers are great. You are building a Galaxie right? .400 higher exhaust ports shouldn't really hurt too bad, maybe a little header work. Most Galaxie headers hang too low anyway unless you get lucky like I did. The chambers and better quality flow really weight the BT toward the better side. As Barry said the valvetrain pieces are different, but anything you do needs fitting anyway.
Nothing against the EDs, but they aren't that much better than a set of rebuilt iron heads with the same size valves and some cleanup. Weight makes some difference, but an iron FE head only weighs about 40-45 lbs, the Eds are 25-30 if I remember right, so weight isn't a real reason. Edelbrock needs to step up and make a better head out of the box. They claim 270 cfm out of the box on the intake, but 250-260 is more like it. I have a set of mildly ported C4AE-Gs with 2.09/1.65s that flow that well and kill the Edelbrocks between .200-.400 that were done by Scott Vincent. Barry's are the best prepped and you can take his 270-300 numbers to the bank and bring home change. JMO.
BT heads are the best. They come with washer faces on all head bolt surfaces, Tine Certs in all bolts holes, modern Yates style combustion chambers, exhaust ports that need little to flow good numbers. Flow numbers are in the 390/400 cfm range for intakes and 280/287 cfm for the exhaust.They are also machined to accept T&D rockers without any addditional machining. Disadvanages are they require an custom manifold on the high riser version, a good porter, special rocker arms and cost more bucks. My opinion is that there is no better in line wedge head available for an FE. I have a set of cnc ported Edels on a 511. Soon I will have my BT headed 542 running with the BTs. The dyno will tell the tale. Hoping to get over 900 HP.
