Bullocks Power Service 433 TFS short travel HR - 633 HP @ 6200 13 in/hg vac

[My427stang]

Performance Summary:
      Cubic Inches:  433            Dyno brand:  Stuska
      Power Adder:                    Where dynoed:  Dale Meers Racing Engines, Buffalo, KY
      Peak Horsepower:  633 @ 6200
      Peak Torque:  558 @ 5500 586 @ 4800 (Thanks Jay for catching error)


Engine Specifications:
   Block brand, material, finished bore size, other notes:  Factory 428 industrial ribbed casting, 4.160
     
   Crankshaft brand, cast or forged, stroke, journal size: Cast SCAT 3.98
     
   Connecting Rods brand, material, center to center distance, end sizes, bolts:  Eagle H-beam 6.49

   Piston brand, material (caster, hypereutectic or forged), dish/dome volume, static CR:  Ross  XL412-2 Forged, flat top with 6cc valve relief, 11.5:1

   Main Bearings, Rod Bearings, Cam Bearings brand and size:  Calico coated FM main bearings, Calico coated Clevite rod bearings, Durabond cam bearings

   Piston rings brand, size, other notes:  Total Seal, 1/16. 1/16, 3/16, gapless top

   Oil Pump, pickup, and drive:  Melling M57HV, Kevko pickup, ARP drive

   Oil pan, windage tray, oil filter adapter:  Kevko rar sump, factory oil filter adapter

   Camshaft brand, type (hyd/solid, flat tappet or roller), lift and duration (adv and @.050"):  Custom Bullocks hyd roller, 241 intake duration, 115 LSA on 107

   Lifters brand, type:  Morel short travel

   Timing chain and timing cover: Cloyes billet w. torrington bearing, factory timing cover

   Cylinder heads brand, material, port and chamber information:  Out of the box TFS, 69.8 cc
 
   Valve springs brand, part number, specs:  7256-16 Comp Conical 190/495

   Retainers and locks brand, part number, specs:  1787-16 Tool Steel and matching locks

   Rocker arm brand, type (adjustable or non-adj), material, ratio:  Precision Oil Pumps

   Rocker shafts and stands, brand, material:  Precision Oil Pumps

   Pushrods brand, type, length:  Trend, 5/16", .105", 8.875

   Valve covers, brand, type:   Aluminum fabricated

   Distributor brand, advance curve information:  MSD, locked out

   Harmonic balancer brand:  Powerbond

   Water pump brand, type (mechanical or electric):   Tuff Stuff Aluminum electric powered on dyno

   Intake manifold brand, material, porting information:  Victor 427, light blend on roof of plenum and port blend, no porting or balancing

   Carburetor(s) brand, type:  QFT STreet Q series, 950 CFM mechanical secondary with 1/2 inch 4 hole Super Sucker

   Exhaust manifolds or headers brand, type:  Dyno headers, 2" tubes

[jayb]

Ross, that is an extremely narrow band between peak torque and peak HP.  Usually, the spread between peak torque and peak HP is around 1500 RPM.  This engine is only 700 RPM, which to my way of thinking is way out of wack.  What do you attribute this to?  I have my opinion, of course, which is the hydraulic roller cam.  I think a solid roller with the same specs as the hydraulic would have made a bunch more power and peaked up at 7000 RPM.  Not throwing stones, just curious of what your take is on this...

[My427stang]

Ross, that is an extremely narrow band between peak torque and peak HP.  Usually, the spread between peak torque and peak HP is around 1500 RPM.  This engine is only 700 RPM, which to my way of thinking is way out of wack.  What do you attribute this to?  I have my opinion, of course, which is the hydraulic roller cam.  I think a solid roller with the same specs as the hydraulic would have made a bunch more power and peaked up at 7000 RPM.  Not throwing stones, just curious of what your take is on this...

Jay, great catch, not really a typo, but some goofy dyno sheet antics when I went back and looked.  I will correct it

I should have looked closer at all the values on that table.  I grabbed the "peak" as ID'd on the dyno table itself, but it actually had 586 ft lbs at 4800, then dropped a bit as you'd expect and the peak number identified was not right, it isn't even the highest number....

I have a curve plot that shows 4750 as a peak,   In that case it's 621 @   6200 and 575 @ 4750 but those are smoothed. I tend to not post the smoothed numbers

I will say though, this one was a neat one for experimentation. We made a ton of runs and when we were experimenting with way too much spacer and it was hard for the operator to drive the Stuska dyno with the added plenum  Even played with a smaller carb, The peak values didn't change more than a few HP but the engine was not happy with more plenum.  In the end I think we are seeing that 433 inches doesn't act like 482 or higher

As far as the solid roller, no desire to spin a stock 428 that high, especially for this application, this build was intended to be a reliable racer geared for a 6200-6400 rpm peak. That's why only a 241 duration cam as well.  Always ways to make more power, but this was purposeful. 

I'd also add that maybe not a BUNCH more power with a solid roller, this is at 1.46 per cid, which is pretty stout for a 6200 rpm motor with no porting at all.  Although we used a good thick 428, it's still a studded pass car block pulling a BIG sled with tires potentially hopping etc.  In fact, if I was going to do better, I had zero valve float well past the peaks and carried up through through 6600, so if I were to change anything, I'd likely just rub on the intake and heads first.

The next version for the truck will be an iron high riser with an aftermarket block, will be more bold with that one


 

[jayb]

That new peak torque number and RPM makes a lot more sense, and I retract my comment about the cam in light of the lower peak torque RPM.  It wouldn't make a lot of sense to spin it too much higher in light of that - Jay

[My427stang]

That new peak torque number and RPM makes a lot more sense, and I retract my comment about the cam in light of the lower peak torque RPM.  It wouldn't make a lot of sense to spin it too much higher in light of that - Jay

I do appreciate the catch, always hate to be saved from myself, but happens every so often 

ON EDIT:  For the crowd, what Jay was referring to is that if I really had a 5500 torque peak and HP peaked at 6200, it likely would be an issue with something else, like valve float, fuel starvation, etc.  However, with a torque peak where it was, it makes sense, the cam is doing exactly what it was designed to do.  Shame on me for not catching my mistake today when I initially posted the TQ numbers

[blykins]

It's a nice engine.  Glad we got to hang out.  It's always fun to be at the dyno when it's not your engine.

[My427stang]

It's a nice engine.  Glad we got to hang out.  It's always fun to be at the dyno when it's not your engine.

Indeed, I tell Michelle I go to Kentucky to see you and while I am there I dyno an engine or two   I appreciate you taking time from your hectic schedule too.  If only Nebraska and Kentucky were closer

[Stangman]

Looks like you guys had a good day. That’s a potent little motor you got there Ross. All that and enough vacuum for power brakes. The horsepower numbers are going up on the FE thanks to all you guys. The TFS heads are doing pretty well I would say. Impressive on a 433 though those numbers are 482 numbers. Congrats keep up the good work and what is that motor going in.

[My427stang]

Looks like you guys had a good day. That’s a potent little motor you got there Ross. All that and enough vacuum for power brakes. The horsepower numbers are going up on the FE thanks to all you guys. The TFS heads are doing pretty well I would say. Impressive on a 433 though those numbers are 482 numbers. Congrats keep up the good work and what is that motor going in.

The owner has a F250 Ford 4x4, 1968 or 1969, going to be a truck puller.  Spin it up and let the the sled drag it down