Ok so first I appologise for screwing up the first build sheet posted I was working on, so after noting to self not to have more than 1 engines notes written down in front of me at one time here is the correct spec sheet for a potential build up of a 77' Pontiac 400. Right now were in the initial stages of looking to take the ole gal and put a fire under the seat. I know pushing a 77' cast 500HP+ is not a good idea so no I don't want to go that far. However that being said I would like some input into potential tweaking of the numbers with maybe a slightly different setup. I punched these numbers in for the estimated HP/TQ which are estimates only. I do know paper is one thing dyno is another. So hopefully i didn't make any errors this time since I did make sure and only had one motors notes out at one time! Thanks in advance for any pointers or input. I would like to boost or maintain the HP/TQ estimates while bringing down the compression to around 9.5-9.7:1 if possible. It is also a goal to keep cost within reason so no im not even going to ask for the cheapo buildup ideas, cheap = more cost down the road.


Pontiac 400 (6.6 liter) 1967-1979
Cubic Inch Displacement 405.8ci +.030 Over Stock Bore W/ 10:1 Compression on Pump Gas. All balancing to within .1 Gram Tolerance

BLOCK: Cast Steel Crank W/ Performance Balance
Pistons H Series Premium Forged Flat Top
Bore 4.150 (+.030 Over)
Stroke 3.750
Main Journal 3.00
Rod Journal 2.250
Connecting Rods:
Forged 6.625 H-Beam W/ 3/8” Cap Screws
Piston to Deck .030 Head Gasket .039”
Piston Dished -5.00cc Flat Top Valve Relief Cut
HEADS: *note final number based on port & polish gasket matched job
Compression Ratio W/ 72 cc Combustion Chamber 10:1
Edelbrock D Port Performer (Bare)
72cc Combustion Chamber
Intake Runner Volume 204cc
Exhaust Runner Volume 145cc
Intake Valve 2.11
Exhaust Valve 1.66
Valve Spring Diameter 1.46” 120 lbs @ 1.800 Installed Height
Cam:
Cam #Magnum 51-240-4 292H
RPM Range 2500-6500
*Required 3000 Stall 9.5:1 Compression *minimum compression ratio
Advance Duration Degrees 292 Int 292 Exh
Lobe Separation 110 Degrees
Centerline 106 Degrees
Valve Lift .501 Int .501 Exh @.50 In Lift
Valve Timing @ .006 Lift
Exhaust Closes 32 ATDC Opens 80 BTDC
Intake Opens 40 BTDC Closes 72 ATDC
Gross Lift (1.65:1 Ratio Rockers) .411 Int .446 Exh
Gross Lift (1.50:1 Ratio Rockers) .374 Int .406 Exh
Intake Manifold
Edlebrock Performer RPM Series
1500-6500 RPM
Carburetion:
Holley 0-4779C 750 CFM Double Pumper
Estimated Numbers
405.8 ci Displacement
452.79 HP @ 6600 RPM 466.07 Ft Lbs Tq @ 4337 RPM(@ Flywheel)
Engine CFM 801
Volumetric Efficiency 103.07%
Compression Ratio 10.01:1
Estimated Wheel HP Based on Upgraded Transmission 369.94 HP
Octane Rating 90