Pontiac 400 Engine Build - Pump Gas Pounder
Will TIP's 400 Block/KRE Head Combo Produce More Than 600 HP On 93-Octane?
From the September, 2008 issue of High Performance Pontiac
By John Carollo
Photography by John Carollo
Everyone wants to build a better mousetrap. Some like to compete in the high-compression horsepower chase and some look to push the boundaries of the pump-gas combo. For this story, Tin Indian Performance (TIP) and Kauffman Racing Equipment (KRE) set out to do the latter using a factory Pontiac block, KRE's D-port heads, and various new products introduced by both companies. Ultimately, the engine is destined for TIP's Kevin Swaney's 3,500-pound race car, in which he's intent on running mid-10s.
The major components of the build up include a '67 GTO 400 block previously freshened up by Kevin. It was punched 0.035-over and stuffed with a 4.210-inch stroke crank. Aluminum rods will keep reciprocating weight down, a stout Comp roller cam will provide big duration and lift numbers to draw a copious amount of atmosphere through the KRE D-ports via a Holley 1050 Dominator and Victor intake. MSD components will light it off and combustion remains will be expelled via Hedman 1.75-inch Hedders.
The 400 block has been fitted...
The 400 block has been fitted with a 455 nodular cast iron crank that was cut down to 3-inch mains. An Oldsmobile thrust-bearing was employed with a shim. This short-block was originally built some years ago, before aftermarket cranks became widely available. If you decide to build a similar combo, an aftermarket crank is the way to go today. BME aluminum rods and SRP forged pistons round out the reciprocating assembly. The factory 2-bolt mains and stock caps are retained and the owner and builder of this engine-Kevin Swaney of TIP-says the bottom end will hold up, even with a possible 650 hp on tap.
KRE's aluminum D-ports are available in three different chamber sizes-65, 74, and 85 cc-and are CNC-ported to flow 310, 325, or 340 cfm. They also accept existing D-port headers and all stock Pontiac engine parts. For this engine, TIP will use the 74cc 340-cfm versions to keep compression pump-gas friendly at 11.4:1 while still providing enough airflow to produce 600-plus hp.
Follow the photos and captions to learn more and check the Engine Buildup Worksheet for further details. Then we'll see how the engine performs on the dyno. Will this two-bolt main 400 block fitted with go-fast goodies make 600-plus hp on the dyno on 93-octane and live to tell the tale? Read on.
|Engine Buildup Worksheet|
|Block/Crank Combo||400 block, bored 0.035-in/stock 4.210, |
|stroke 455 crank|
|Block Description||'67 400 |
|Preparation||Clean and mag, fill to water jackets with hardblock,|
bore and finish-hone to size using a torque
plate, wash and assemble
|Crank||455 turned down to 3-in mains|
|Preparation||Balance rotating assembly|
|Balancer||Professional Products SFI-approved|
|Rods||BME aluminum, 6.625-in, 0.020-in side clearance |
|Bearings||Federal Mogul, main clearance 0.0025-in, rod clearance 0.003-in|
|Preparation||Oil feed holes opened up|
|Pistons||SRP 4.185-in forged, 0.005 piston-to-wall clearance|
|Piston to Deck Height||0.005-in|
|Piston Pins||SRP with spiral locks|
|Rings||Total Seal 1/16-, 1/16-, 3/16-in, Moly top, cast iron second|
|Preparation||Filed-to-fit, 0.018-in gaps|
|Rod Bolts||ARP 2000|
|Crank Scraper||Tin Indian Performance|
|Oil Pump||Melling M54ds|
|Preparation||Spring shimmed to increase pressure|
As you can see, the short-block...
As you can see, the short-block already has some running time on it. The SRP pistons feature 7cc valve reliefs and piston to deck height is 0.005-inch.
KRE's aluminum timing chain...
KRE's aluminum timing chain cover, already painted the correct blue, installs over the Rollmaster timing chain. Note the white Teflon TIP gasket.
Here are the 340-cfm 74cc...
Here are the 340-cfm 74cc KRE aluminum D-ports with the new TIP-KRE340D exhaust gasket, which features a "non-asbestos material with a non-stick coating applied to both sides," according to TIP. The heads are fully machined and ported in-house on a five-axis CNC.
|Brand||340-cfm, 74cc KRE aluminum D-ports|
|Head Mods||Gasket match to TIP-120240 intake gasket, |
CNC-ported to 340-cfm
|Combustion Chamber Volume||74 cc's|
|Maximum Flow at 28 Inches of Water|
|Intake||341-cfm at 0.700 lift|
|Exhaust||261-cfm at 0.700 lift|
|Valves||Ferrea SS 6000 series, 2.19/1.66-in|
|Retainers||Comp Cams 10-deg|
|Keepers||Comp Cams 10-deg|
|Rocker Arms||Scorpion 1.6-ratio full roller|
|Pushrods||Comp Cams, 5/16-in, 9.450-in long|
|Brand||Comp Cams custom-grind solid roller|
|Duration at 0.050||265/272-deg|
|Lobe Separation Angle||110-deg|
|Lifters Brand||Crower roller|
|Timing Chain||Rollmaster double-roller|
|Carb||1050 Holley Dominator|
|Jets||No. 97 square|
|Intake Manifold||Edelbrock Victor 850 base with tapered spacer|
|Mods||Ports matched to heads|
|Coil Brand||MSD blaster|
|Spark Plugs||NKG No. 8|
|Total Timing||31.5-deg advance locked out|
This is the business end of...
This is the business end of the heart-shaped, fast-burn combustion chamber. Note the spark plug hole is canted toward the exhaust valve, as it's the hottest area of the chamber, providing a quicker and more complete burn. You can also see the bowl work on the intake side. The 30-45-60-degree multi-angle valve job was performed at KRE with a new, state-of-the-art Rottler SG-8 seat and guide machine.
Here's the intake side of...
Here's the intake side of the KRE aluminum heads that were ported to flow 340 cfm.
Ferrea 6000 series stainless...
Ferrea 6000 series stainless steel valves; 2.19-inch intake and 1.66-inch exhaust feature 45-degree seats and a 30-degree back cut on the intake.
Baseline numbers were established on KRE's Superflow 901 engine dyno. Horsepower checked in at 614 at 6,200 rpm on the first pull. Torque was 563 at 4,600 rpm. Not a bad start. Baseline tuning consisted of No. 97 jets square, 28-degrees timing, and 0.020/0.020-inch valve lash.
|Best Dyno Pull|
The Cometic 0.040 head gasket...
The Cometic 0.040 head gasket is shown in place just prior to mounting the passenger side head. Note the use of ARP studs-highly recommended at this power level.
The Comp Cams custom grind...
The Comp Cams custom grind solid roller cam features 265/272-degrees duration at 0.050 and 0.691/0.691-inch lift. Crower roller lifters are employed and, though the Comp Cams valvesprings have an open pressure of 620 pounds, Kevin feels that a lifter bore brace isn't needed with this camshaft profile but a KRE stud girdle certainly is needed to maintain the proper valvetrain geometry by preventing stud deflection. Kevin says, "These CNC-machined 6061 T-6 aluminum systems are lightweight, durable, and easy to install." Beneath it are Scorpion 1.6:1 roller rockers.
The new TIP-120240 intake...
The new TIP-120240 intake gasket is specifically designed to accommodate the intake port size of the KRE head.
Once the other stud girdle...
Once the other stud girdle is installed, the KRE valley pan goes on using silicone to seal it.
A Holley 1050 Dominator carb...
A Holley 1050 Dominator carb is mated to the Edelbrock Victor intake's 850-cfm carb-style flange via an adaptor.
Over the course of 13 dyno pulls, Kevin and Jeff did the usual tuning with jets, valve lash, and timing. In the end, No. 97 jets square, 0.030/0.020 valve lash, and 31.5 degrees timing produced 650.4 hp at 6,300 and 596 lb-ft of torque at 4,900 rpm. We learned during tuning that advancing the timing past 32 degrees had a detrimental effect on power and the heads made peak power with 31.5 degrees of total timing. More power may be possible with more tuning, but dyno time was at a premium. Nevertheless, the mission was accomplished.
On The Dyno In the dyno cell,...
On The Dyno In the dyno cell, the timing is checked on the 463 before a pull is made.
An MSD Pro Billet distributor...
An MSD Pro Billet distributor featuring a TIP prototype polymer distributor gear, locked out mechanical advance, and Taylor wires handle the spark.
The TIP crank mandrel drive...
The TIP crank mandrel drive system is mounted to the Professional Products SFI balancer and is used for driving belts and running the Moroso four-vane enhanced vacuum pump.