495-cid Pontiac Powerhouse

By Lyle Larson
So Von Neal of Von's Transmissions in San Bernardino, CA is building this cool '65 Pontiac Tempest with an Art Morrison chassis and he want's to highlight the build with a strong, all Pontiac powerplant. He starts with a 400 block and the aluminum lifter bore reinforcement braces, but decides that's not trick enough for the hot street car he is building. So he goes all-in with a Kauffman Racing Equipment block that offers all the most desirable features and eliminates the fickle problems that crop up when stroking a factory block. The stock block gets replaced with a Kauffman MR-1 iron block to accommodate a SCAT 4.5-inch forged stroker crank yielding 495 cubic inches. The Kauffman block has thicker deck surfaces and comes with splayed billet steel 4-bolt main caps. It accepts large bores and stroke sizes and features a dual bellhousing bolt pattern. The MR1 block is designed to accept all stock Pontiac parts and the lifter galley is fully reinforced so no additional lifter bore bracing is required.
Factory Pontiac blocks like this 400 version are historically weak in the lifter bore area and some aftermarket manufacturers have offered these aluminum reinforcement plates to reinforce the lifter bosses for use with more aggressive cams and higher valve spring pressures.. Von began his project with one of these kits and decided he didn't really like it so he sprang for a new Kauffman MR-1 block instead. The finished bore size is 4.185-inch which yields 495 cubic inches with SCAT's 4.5-inch stroker crankshaft; an under square engine that should deliver gobs of low end and mid-range power without having to scream it up too far. Perfect for a hot street car. To ensure a top quality build, he turned to his friend in the shop next door, David Basham at Basham Motorsports.
Kauffman's MR-1 block features billet steel main caps with provisions for a windage tray attached to ARP studs. Main bearing clearance is set at .003-inch. Note the 12 point nuts on the rear main studs to ensure pan clearance. Engine builder David Basham always installs the camshaft before he short blocks the rest of the bottom end to makes it easier to install and inspect. The cam is a Bullet solid roller with 267/270 duration at .050-inch lift and .742/.728-inch net lift on a 110 degree centerline.  After installing the cam, he lays the crank in with the number one rod and piston to verify deck height and degree the cam. Decks are previously checked and machined parallel during the mock up assembly. This combination is zero decked.
Basham uses a lifter bore dial indicator and the Altronics DIGICAM tool to degree his cams. The DIGICAM allow for very precise camshaft checking without the need for a degree wheel and pointer. it uses a roller assembly attached to the front of the crankshaft thatreads out in tenths of a degree and automatically calculates TDC, Cam Centerline, and Duration. An integrated Crank Socket permits easy engine rotation and the DIGICAM can also be mounted at any angle so the camshaft can be removed or adjusted without removing the DIGICAM from engine. Another great feature is the lack of a degree wheel so cams can be accurately degreed while still in the car if required. The kit comes with interchangeable crank sockets to fit all popular performance engines.
The SCAT crankshaft anchors  forged Carrillo/Bullet H-beam connecting rods with reinforced beams resembling an I-beam configuration. These are basically big block Chevy spec rods with a center to center length of 6.8-inch for a rod to stroke ratio of 1.49. CP Piston's line of Bullet pistons feature 2618 alloy construction with mild .043-inch domes and valve relieves to accommodate up to 280 degrees duration at .050-inch lift. Final compression ratio with the 74cc chambers in the Kauffman Pontiac cylinder heads is 13.5:1. With the camshaft intake closing event at 74 degrees ABDC it yields an effective compression ratio of 8:1 although Von is planning to run E85 fuel.
David uses a Law Products ring squaring tool for file fitting ring sets. These Bullet pistons use a 1.2mm top, 1.2mm second and 3mm oil ring set with the top ring gaped at  0.018 and the second ring gaped at 0.022. The 0.990 piston pins do not intrude on the pin bore space so no oil ring support rail is necessary.
The CNC chambers measure 74cc.  The intake valve is 2.200-inches and the exhaust valve is a 1.700-inch. Valve lengths are 6.200-inch and the valve angle is 14 degrees allowing them to work with stock pistons if desired. The minimum bore size is 4.150-inch. These heads bolt to standard Pontiac blocks with no problem and they do not require offset lifters. Complete heads come with 1200 series Ferrea valves (better then 6000 series), titanium  retainers, 10 degree locks, PC seals, PAC roller cam springs for .750 lift, ARP rocker studs, spring cups and a 5 angle valve job.
These are "as cast" ports with no machining. They flow about 330 cfm. They can be CNC ported to flow 400 cfm. Von's heads were ported to the 365  cfm level as seen in the photo below. The intake ports allow for standard 3/8-inch diameter Pontiac pushrods and the exhaust ports are the standard Pontiac shape that accepts all headers; although they will sit slightly higher in the car.
Cometic's .040-inch MLS gaskets support the required bore size. This is a 4.200-inch bore gasket designed to support the 4.185-inch bore on this Pontiac build. An interesting note about the Kauffman M1 cylinder block; when checked, the decks were within .002-inch of being dead parallel with the crankshaft centerline. this facilitates an easy cut off each side to zero deck the block to the piston tops.
These are Isky Ez-Roll Red Zone mechanical roller lifters. Von wanted a mechanical roller camshaft which is typically unfriendly to roller lifters on street engines that experience a lot of time idling. The secret here is the solid bushing instead of needle rollers. The lifters feature precision oiling with an exclusive grooved bushing that evenly distributes oil across the load bearing surface. Needle bearings, on the other hand,  present multiple contact points with higher loading at each point than a bushing, hence they tend to pound out over time. The bushed Isky lifters resist this problem. Manton custom pushrods are 10.375-inch by 3/8-inch with heavy duty tips.
A Butler Performance aluminum valley cover rigidly seals the lifter valley. This reinforced cover seals better than the OEM  style tin covers and is available with a PCV boss should you require it. Von is looking pretty happy with the way his engine is going together.
Crower/Kauffman shaft rocker system is specific to the Kauffman aluminum cylinder heads. The individual stands seat on a rigid one-piece mounting bar that runs the length of the cylinder head. These rockers are very rigid to help prevent valve train deflection. Kauffman Racing Equipment also offers a T&D shaft rocker system so take your pick. Both setups are top quality pieces. Basham uses a Jesel adjustment tool which makes accurate valve setting a real snap.
There's plenty of performance hardware attached to the front of this engine. A Kauffman timing cover houses a Butler/Rollmaster billet timing set.  A Meizere 30 gallon per hour electric water pump mounts to the front of it. Below it, an Innovators West billet aluminum harmonic balancer is attached to the crank snout with an ARP balancer bolt. The balancer is equipped with integral flying magnets to accommodate the crank trigger ignition system. On the side, a Kauffman billet cover seals the fuel pump boss since this application uses an electric fuel pump.
Here's the Innovators West crank trigger sensor installed on the supplied mounting bracket. Down below, a Ram Air IV oil pump picks up oil via a Canton pickup specific to the canton pan.
The Canton Racing products oil pan feautures internal baffling and trap doors to ensure that the pickup is always submerged in oil.
Canton pan installed and a distributor drive checking tool used to spin the pump delivered an immediate 80 psi pressure.
The pump was spun and the engine turned over until oil was observed at all the rocker arms. On the right, a March serpentine belt system facilitates driving the alternator, power steering unit and AC compressor along with a separate drive for the the crankcase vacuum pump.  PLEASE NOTE: This story will update with more photos and results as soon as the dyno test is completed.
The carburetor is an E85 specific 1000 CFM four barrel from Carburetor Solutions in Fontana, CA.  909 851-6955
Initial startup and engine break-in session followed by 15 dyno pulls as the fuel curve and timing were optimized for best power.
The engine was tuned to 714 horsepower with an average of 638 lb-ft of torque. Torque was 619 at 3500 rpm and 577 @ 6500rpm. Best power came in as total timing was reduced from 34 degrees down to 28 degrees, indicating a pretty efficient combustion chamber. This was accomplished with E85 gasoline delivering a very high, flat torque curve. The Kauffman heads worked as advertised in the configuration used on this particular engine. With well over 600 lb-ft of torque over the full operating range of the vehicle, this will be a fun ride in a mid-weight street car like Von's 1965 Tempest. As soon as the car is finished, we will feature it on our sister site Alternate Supercars.


Basham Motorsports
1904 Riverview Dr. Suite 101
San Bernardino, CA 92408
909 799-7770

Kauffman Racing Equipment
22280 Temple RD
Glenmont, OH 44628
740 599-5000


Von's Transmissions
1904 Riverview Dr, Ste 103,
San Bernardino, CA 92408
e-mail: pontvon@msn.com
909 838 6581

Mayeda Motorsports
13089 Peyton Drive, Suite C227
Chino Hills, CA 91709
Phone: (909) 590-9324
Fax: (909) 517-1787
e-mail: vincent@mayedamotorsports.com