CHP 408-Dart Pro 1 225 Heads
Obviously, this stroker buildup was not for the timid, as the elevated static compression, wild cam timing, and healthy 950 HP Holley carb were designed with speed in mind. After topping the CHP 408 stroker with the Dart Pro 1 225 CNC heads, a wild solid roller cam from Comp Cams and a Holley 950 HP carb and Super Victor intake, our Pro Street Stroker thumped out 618 hp at 6,600 rpm and 562 lb-ft of torque at 5,100 rpm. Torque production from the big Windsor exceeded both 550 lb-ft from 4,600 rpm to 5,700 rpm and 500 lb-ft from 4,000 rpm (or lower) to 6,500 rpm. The Dart Pro 1 heads offered plenty of airflow to work with the long-duration cam to help produce plenty of high-rpm power. On the wish list for this combination is a set of 1 7/8-inch Hooker headers, a racing oil pan with better windage control, and even a Holley Dominator carb (there was vacuum present with the 950 HP).
| 408 Windsor Spec Sheet |
| Material: | 355T6 aluminum |
| Chamber Size: | 62 cc |
| Intake Valve Material: | Stainless steel |
| Exhaust Valve Material: | Stainless steel |
| Intake Valve Size: | 2.08 |
| Exhaust Valve Size: | 1.60 |
| Intake Port Volume: | 225 cc |
| Exhaust Port Volume: | 87 cc |
| Intake Port Location: | Stock |
| Exhaust Port Location: | Raised 0.135 std and spread bolt patterns |
| Intake Port Dimensions: | 2.150 x 1.300 |
| Exhaust Port Dimensions: | 1.420 x 1.420 |
| Recommended Intake Gasket: | Fel-Pro 1262 |
| Recommended Exhaust Gasket: | Fel-Pro 1487 |
| Recommended Head Bolts: | Dart and 351 1/2 od ARP 154-3603, 302 7/16 = ARP 154-4003 |
| Recommended Head Studs: | Dart and 351 1/2 od ARP 154-4003, 302 7/16 = ARP 154-4005 |
| Intakes: | Most with standard port location |
| Milling: | Min 50 cc (0.0065=1 cc) flat mill |
| Pistons: | Most 20 deg |
| Pushrod Length: | 8.250 (roller cam), always check |
| Guideplates: | Comp Cams No. 4816 |
| Retainers: | 10 deg |
| Spark Plugs: | 0.750 Reach gasketed-Champion C59C/C59YC (Denso IQ24) |
| Spring Pockets: | 1.437D=130 lbs at 1.80 installed height (Hyd roller or flat |
| | tappet) 1.550D=195 lbs at 1.90 installed height (solid roller) |
| Valve Length: | Std 4.890 or 5.015 (+0.100) roller |
| Valve Stem Diameter: | 0.3415-1 1/32 in |
| Recommended Valvetrain: | Accepts roller rockers 3/8 or 7/16 stud mount |
| Valveguides: | 0.5 OD mag bronze (0.002 press) |
| Valveguide Length: | 2.100 in |
| Valveguide Clearance: | 0.0014-0.002 (with 0.3415-dia valve stem) |
| Valveguide Spacing: | 1.876 in (moved 0.050 from stock) |
| Valve Seats: | Hardened ductile-iron 0.006 press |
| Valve Seat Diameter: | Int-2.160 x 1.810 x 0.350 in, Ext-1.650 x 1.350 x 0.350 in |
| Valve Seat Angles: | Int=32 - 45 - 60 - 70 Ext=37 - 45 radius |
| Stud Girdle: | Standard |
| Torque: | Head bolts 7/16 - 70 ft-lb 1/2 - 100 ft-lb |
| Block Use: | Dart iron/aluminum or any production Ford W |
| Weight: | 23 lbs |