- Shipping costs and lead times vary
In the world of racing and performance, BIGGER is always better. Ford Performance gets it - and that's why it offers BOSS small blocks in Big Bore versions. The Ford Performance BOSS blocks are designed to be a replacement for the legendary BOSS 302 and BOSS 351 blocks using the latest technology and manufacturing techniques available. Cast from diesel grade iron with siamese bores, thick cylinder walls and decks, BOSS block strength is far superior to any Ford production block ever offered.
Ford Performance Big Bore version of the BOSS 302 block makes it simpler and more economical to build really BIG small blocks. To insure the most precise bore location, concentricity and integrity, the BOSS Big Bore blocks are machined an additional .125" during the initial block fixturing and boring stage. With an unfinished bore size of 4.120", Ford Performance BOSS 302 Big Bore blocks will support engine sizes up to 363 cubic inches.
The Ford Performance BOSS block capability has been proven around the world, both on the track and on the street. And, all Ford Performance BOSS blocks are cast and machined to the highest industry standards in the USA.
- 4.125" bore capacity, finished at 4.115" rough bore. Also available in standard bore version, part number: M-6010-BOSS302
- 8.2" deck height, finished at 8.200" plus .010" to .015"
- Designed with optimized cylinder wall length for stroker applications up to 3.5" with no grinding or clearancing. (Depends on crank/rod manufacturer)
- Splayed 4-bolt main on 2, 3, 4, main caps
- 2-bolt main on first and fifth main caps
- Main bearing bores finished to low limit
- Finished lifter bores
- Machined to accept factory roller lifter guides and lifter guide retainer
- Fits factory 1979 - 1995 Mustang oil pan with custom oil pickup tube, part number: M-6622-BOSS302
- NASCAR inspired front oil feed on both lifter galleys.
- Revised cooling system passageways
- Siamese bore
- Increased bulkhead material
- Threaded core and galley plugs (straight thread port plugs with O-ring)
- Requires special length 1/2" head bolts M-6065-BOSS or head studs M-6014-BOSS recommended with M-6049-X306/307/Z304DA heads
- Designed for M-6049-X306/X307/X2/C3/D3/Z304DA/Z2 cylinder heads. Not designed for production 302/351W or M-6049-Y302/Y303/X302/X303/X304/X305 cylinder heads
- Uses common OD cam bearings M-6261-J351/R351
- Unique cam plug M-6026-S351 included
- M-6051-S331 or M-6051-CP331 head gasket recommended
- Designed to be compatible with the original 302 and 351W blocks and includes the following features:
- Designed to use stock type timing cover, timing Cover M-6059-D351 recommended (includes fuel pump provision)
- Fits factory Mustang oil pan with custom oil pick-up tube M-6622-BOSS302
- Retains clutch cross shaft pivot hole
- Original Style oil filter location
- Original motor mount boss locations
- Original bell housing pattern
- Weighs approximately 163 lbs.
- Great price and value
- The foundation for 8.2" deck projects
Proven performance - used in Ford Performance sealed 347cid race engines and Ford Performance high performance crate engines, a proven winner out of the crate and thousands of laps before rebuild.
Shipping costs and lead times can vary, use the contact form below to confirm order cost and timeframe.
We have a 30-day return policy, which means you have 30 days after receiving your item to request a return.
To be eligible for a return, your item must be in the same condition that you received it, unworn or unused, with tags, and in its original packaging. You’ll also need the receipt or proof of purchase.
To start a return, you can contact us at brian@paulsautomotiveengineering.com. Please note that returns will need to be sent to the following address: 9750 Conklin Road Blue Ash, OH 45242
If your return is accepted, we’ll send you a return shipping label, as well as instructions on how and where to send your package. Items sent back to us without first requesting a return will not be accepted.
You can always contact us for any return question at brian@paulsautomotiveengineering.com.
Damages and issues
Please inspect your order upon reception and contact us immediately if the item is defective, damaged or if you receive the wrong item, so that we can evaluate the issue and make it right. If we do not receive notice within 7 days of receiving order, we cannot process return.
Exceptions / non-returnable items
Unfortunately, we cannot accept returns on sale items or gift cards.
Exchanges
The fastest way to ensure you get what you want is to return the item you have, and once the return is accepted, make a separate purchase for the new item.
Refunds
We will notify you once we’ve received and inspected your return, and let you know if the refund was approved or not. If approved, you’ll be automatically refunded on your original payment method within 10 business days. Please remember it can take some time for your bank or credit card company to process and post the refund too.
If more than 15 business days have passed since we’ve approved your return, please contact us at brian@paulsautomotiveengineering.com.
