This Dart cylinder head is engraved with IMCA logo and serial numbered to make it approved for use in IMCA classes that allow the CH350I cylinder head, High-velocity 165cc/65cc intake/exhaust runners deliver strong mid-range torque, Assembled versions include 1.94"/1.50" standard length stainless steel valves, performance valve springs, retainers, keepers and 3/8 screw-in studs, SM version (Sport Mod) also has upgraded Comp Cams valve springs and lightweight Ferrea tool steel retainers, SC version (Stock Car) also has upgraded Comp Cams valve springs, lightweight Ferrea tool steel retainers. 080 milled deck w/ corrected intake for max compression.
Dart IMCA Approved Bare Cast Iron Small Block Chevy Cylinder Head. IMCA Approved Stock Replacement Dart Cylinder Heads. These Dart IMCA Approved cast iron Small Block Chevy cylinder heads are approved stock replacement heads for Hobby Stock, Northern & Southern Sport Mod, and Stock Car classes (using the 500 carbuertor).
We begin with a Dart 10024360 Iron Eagle S/S 165 casting. Each head is engraved and serial-numbered to conform to IMCA rules.
Featuring precision cast ports and chambers, they have outstanding air flow. Assembled versions have optimized valve sizes for maximum performance within IMCA rules.
(BARE) - Bare Cylinder Head. (HS) - IMCA Hobby Stock Heads. (SM) - IMCA Sport Mod Heads (Northern and Southern SportMod).
(SC) - IMCA Stock Car Heads. (SCBARE) - IMCA Stock Car Bare Cylinder Heads.
Complete assembled versions include high-performance springs, 1.94"/1.50" standard length stainless steel valves, 7 degree locks and steel retainers with 3-angle valve jobs. Sport Mod and Stock Car versions includes high-performance COMP Cams valve springs and handle 0.550 net valve lift, with Ferrea tool steel retainers. 080 max flat milled w/ intake surface corrected to max out the compression rule for the IMCA Stock Car. Hobby Stock heads feature Speedway Motors.Approved for IMCA Hobby Stock, Sport Mod and Stock Car classes (using 500 carb) as of 4/27/2020. Comb Chambers: 64cc (SC) 76cc (SM/HS/BARE). Intake Valve Dia: 1.940.
Intake Port Dim: 1.100" W x 1.925" H. Intake Gasket: Fel-Pro# 1204 or OEM type.
Exhaust Port Dim: 1.340" W x 1.300" H. Exh Port Location: Stock location & bolt pattern. Head bolts: Stock bolts can be used. 0065 = 1cc Flat Mill. Pistons: Most 23° aftermarket pistons. Push Rod length: Stock (Stock length = 7.800) Must measure. Push Rod Guide: Stock type, integral.Retainers: Steel 1.250 = (7°). Rocker Arm stud: Use screw-in stud w/integral nut. Spring Cups: N/A, Use hardened shim or locator. Spring Pockets: Cut for 1.250 OD.
Valve Length: STD = 4.890. Valve Guides: Integral cast into head. Valve Guide Spacing: 1.890 moved. Valve Seals: Cut for umbrella seals. Valve Seats: Exh = Powdered Metal. Valve Seat dim: Exh - 1.650" x 1.280" x. Int = 32° - 45° - 60° - 70°- 80°. Exh = 37° - 45° - radius. Head Bolts = 70 ft/lb (w/ oil). Rocker Studs = 55 ft/lb. Block Use: Any SBC, Iron or Aluminum. Weight: 52 lbs Bare - 58 lbs Assembled.Nice casting but all 4 required surfacing. By JP on October 15, 2021. Way cleaner casting quality than the EQ counterpart we were using prior.
Made in the USA is a big plus for me. Required 2 passes on the surfacing machine to get them truly flat so you will spend a little on the touch up. Seats were spot on and sealed perfect out of the box. Spring pocket depth was spot on consistent.Yes, I recommend this product. I recommend this product to anyone.
By Trev on January 26, 2021. Related Items / Suggested Parts. COMP Cams 502-16 Valve Stem Seals, Rubber. 344 Inch, Set of 16. Speedway Motors is America's Oldest Speed Shop® and has been a trusted source for specialty rodding and racing products and friendly expert advice for more than 72 years.