Promo
HIGH DEMAND ALERT: Shipping may be slightly delayed!
Thank you for making our Black Friday Sale such a huge success! Due to the overwhelming demand, some orders placed during the sale are still being processed. If your Black Friday order is pending, rest assured that it will be shipped soon.
For new orders, please note that slight shipping delays may still occur as our team continues working around the clock to fulfill all orders as quickly as possible. We deeply appreciate your patience and support during this busy time. Stock is moving fast, so don’t wait—shop now to secure your favorites!
Thank you for making our Black Friday Sale such a huge success! Due to the overwhelming demand, some orders placed during the sale are still being processed. If your Black Friday order is pending, rest assured that it will be shipped soon.
For new orders, please note that slight shipping delays may still occur as our team continues working around the clock to fulfill all orders as quickly as possible. We deeply appreciate your patience and support during this busy time. Stock is moving fast, so don’t wait—shop now to secure your favorites!
Speedmaster®
Chevy SBC 350 B-4.000 M-350 DH-9.025 4-Bolt Billet Main Bare Iron Engine Block
Overview
If your standard Bowtie block could handle 1500+ HP it would be Speedmaster's H1 engine block. Design from the ground up based upon your favourite bowtie block with the ability to handle naturally aspirated, supercharged, turbocharged and nitrous applications.
Specs
| Brand: | Speedmaster |
| Part Number: | 1-286-001-01 |
| Part Type: | Engines, Bare Blocks |
| Product Line: | H1 |
| Cylinder Bore Diameter: | 4.000 in. |
| Bore & Stroke: | 4.185 in. x 4.000 in. Max Recommended |
| Cam Journal OD: | Standard SBC - 1.869 |
| Cam Plug: | 2.375 in. Dia. Cup Plug |
| Cylinder Wall Thickness: | 0.275 in. min @ 4.185 in. Bore |
| Deck Height: | 9.025 in. |
| Deck Thickness: | 0.675 in. Min |
| Fuel Pump : | Standard Mechanical Provision |
| Fuel Pump Pushrod: | Standard Length |
| Freeze Plugs: | 10 x 1-5/8 in. Press In Cup Plugs |
| Lifter Bores: | SBC 0.8427-0.8437 in. |
| Main Bearing Size: | 2.450 in. (SBC 350) |
| Main Bearing Bore: | 2.649 in. (SBC 350) |
| Main Cap Bolts: | #1 7/16 in. (2) 3/8 in. (2) #2, 3, 4 7/16 (2) Splayed (2) #5 7/16 in. (2) 3/8 in. (2) |
| Main Cap Press: | 0.005 in. |
| Main Caps: | All 5 Billet Steel. 3 Center Caps Splayed |
| Main Cap Register: | Deep Stepped Register (No Need for Dowels) |
| Oil System: | Wet Sump - Main Priority Oiling (Can Use Dry Sump) |
| Oil Pump Shaft: | 350 0.481 in. OD - Standard |
| Oil Filter: | SBC, Uses 2 Bolt Adapter |
| Oil Pan: | Standard 350 SBC |
| Rear Main Seal: | Standard 350 SBC |
| Serial No. Location: | Laft Front & Main Caps |
| Starter: | Standard SBC |
| Stud Holes, Head: | Blind Holes |
| Timing Chain/Gears: | Standard SBC Components |
| Timing Cover: | Standard Cam Location SBC |
| Torque Specs: | 1 - 5 7/16 in. Bolts 65 ft. lbs. 1 & 5 3/8 in. Bolts - 35 ft. lbs. |
| Weight: | 205 Lbs @ 4.0 in. Bore |
| Quantity: | Sold individually. |
| Notes: | Cam Bearings not Included, Replaces Dart 31181111 |
| Calculator: | CFM Calculator |
Description
The Speedmaster H1 is the perfect starting point for a powerful and reliable engine build suited for the street or race track. Precision pre-machining is the perfect starting point for a powerful and reliable engine eliminating time and expense of blueprinting a stock block or ''semi-finished'' factory casting. Best of all can be used with standard off the shelf small block components.
Speedmaster H1 Chevy SBC bare blocks feature:
- Cast from premium high-strength Class 32B iron
- Standard deck height allows the use of off the shelf parts
- Uses standard small block Camshaft, Timing Chain, Oil pump, Oil filter, Motor Mounts.
- Priority main oiling system directs oil to main bearings
- Blind tapped head bolt holes prevent water leaks
- Extra thick decks ensure reliable head gasket seal
- Billet steel 4-bolt main caps (splayed for extra strength)
- Front and rear external oil feed, crossover and restrictor provision
- Simplified plumbing for external pumps
- Used in 1500+HP Applications
Prop 65 Warning
This product may contain chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.