Ignition
It's hard to beat an HEI for simplicity and outright spark generating capability. With the right module and coil, these units will service the ignition requirements of any race small-block that even remotely falls into the budget category. One of the best deals that can be had is PerTronix. Our billet body HEI with a performance coil, wires, and module was good to over 7,500 rpm, and cost only $262. It came with a pack of advance springs, so we could trim the advance curve to suit our relatively big cam. Also, our distributor was ordered with the vacuum advance. Because most race engines don't use vacuum advance, why are we? This is a street/strip engine, and we don't want to give away any fuel economy.
On The Dyno
With the BG carb optimally jetted, and the timing set to 34 degrees total, the engine pulled a solid 444 lb-ft and a shade more than 470 hp, and was most certainly still streetable. No doubt those 180cc port EQ 23 heads had something to do with this. Check out the graph for the total power/torque curves.
All this came for a total cost of $3,075, and considering the many new parts used, it is a heck of a good price for the output. We could've cut costs further by spending more time on the Internet looking for better deals, but the key component is the EQ 23 head, which puts you way ahead in the hp-per-dollar game.
EQ 23 FLOW TEST |
| LIFT | INT. | EXH. | EXH./INT. |
| | CFM | CFM | PERCENT |
| .50 | 35 | 28 | 80.0 |
| .100 | 67 | 56 | 83.6 |
| .150 | 102 | 83 | 81.4 |
| .200 | 134 | 110 | 82.1 |
| .250 | 162 | 124 | 76.5 |
| .300 | 185 | 140 | 75.7 |
| .350 | 202 | 158 | 78.2 |
| .400 | 216 | 175 | 81.0 |
| .500 | 237 | 188 | 79.3 |
| .600 | 244 | 190 | 77.9 |
| .700 | 247 | 192 | 77.7 |
As these figures show, the intake flow is strong in the low- and mid-lift range, but levels out somewhat at .550-inch lift. This indicates the 180cc port is being well utilized in terms of port velocity and the chamber form is ideally suited to valve lift up to about .550.
WHERE THE MONEY WENT |
| Short-block core | $300 |
| Freeze plug kit: | $10 |
| KB pistons: | $237 |
| Rings: | $25 |
| Bearings: | $62 |
| Gasket set: | $45 |
| Cam: | $255 |
| Timing set: | $51 |
| Pushrods: | $87 |
| EQ 23 heads (bare): | $478 |
| Valves: | $136 |
| Valve stem seals: | $25 |
| Valvesprings: | $87 |
| Retainers: | $41 |
| Rocker arms: | $200 |
| Intake manifold: | $130 |
| Carb: | $300 |
| Carb spacer: | $25 |
| Distributor: | $220 |
| Plug wires: | $42 |
| Spark plugs: | $24 |
| Used valve covers: | $30 |
| Misc. supplies: | $45 |
| Machine shop labor: |
| Bore & hone: | $150 |
| Cam bearings: | $50 |
| Polish crank: | $20 |
| Total: | $3,075 |
 After a 35-minute break-in...  After a 35-minute break-in and 45 minutes of carb and distributor calibration, our EQ-equipped 350 produced these power curves. Peaks were 470 hp and 444 lb-ft. As for streetability, the EQ heads made 327 lb-ft at just 2,200 rpm, and with the aid of a vacuum-advance distributor, still idled steady at 750 rpm. |
 Here's Son of Sledgehammer,...  Here's Son of Sledgehammer, ready to do battle with the dyno. We cheated a bit by painting the iron EQ 23 heads with high-temp Dupli-Color aluminum paint (PN DE 1650, $5.99). It's a dead-wringer for real cast aluminum, it resists temps up to 1,200 degrees, and has a tough ceramic formulation. As you can see, it looked really good regardless of its low-cash origins. |
 Dyno Test: EQ 23 Heads on...  Dyno Test:
EQ 23 Heads on 350 SB Chevy |