Barn-Find 409 Engine Rebuild - Unearthing A Legend, Part 1

We Take a Mysterious, Barn-Fresh 409 and Turn it Into a Performer.

Tommy Lee Byrd May 7, 2014 0 Comment(s)
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409 Engine Clean 2/26

13 Any time you're threading fasteners into an old block, it's a good idea to use a tap to clean out the boltholes. Since the bottom end was together when we found the 409, the boltholes for the main caps were in good shape. The cylinder head boltholes needed the most attention.

409 Engine Arp Main 3/26

14 ARP main studs are threaded into the block and hand-tightened. ARP suggests hand-tightening the studs to ensure proper torque specifications when the nuts are installed.

409 Engine Install 4/26

15 Since the main journals were in great condition, we used standard bearings, opting for the Clevite brand. At this point, we installed the bearings into the block, making sure they were positioned correctly. Then we gave the bearings a healthy dose of heavy weight oil for lubrication.

409 Engine Install 5/26

16 Crankshaft installation is a two-man job. We lowered the crankshaft into place, making sure none of the bearings moved as we sat it into its final resting place.

409 Engine Main 6/26

17 The main caps can now be fit with new Clevite bearings. Heavy weight oil is used to coat the bearings. Also note the blue main seal and two small-black rubber end pieces. These are essential items, and they are included in all Fel-Pro 409 gasket sets.

409 Engine Arp Ultra Torque Fastener 7/26

18 After sliding all of the main caps into place, we gave the studs a coating of ARP Ultra-Torque fastener assembly lubricant. Old-school engine builders used regular motor oil for years, but Ultra-Torque lubricant ensures proper torque specifications.

409 Engine Install Arp Washers And 8/26

19 We installed the ARP washers and nuts and then torqued them to 110 ft-lb in three equal steps. This torque specification is only accurate when Ultra-Torque lubricant is used, and keep in mind that these torque specs do not apply to original-style bolts.

409 Engine Mr Gasket 9/26

20 All 409 engines came with a canister-style oil filter, so we used a Mr. Gasket kit to swap it to a more conventional spin-on filter. We used PN 1270, which calls for an AC PF-25 filter. That part number is discontinued, so we had the local parts store cross it out with a Wix brand, No. 51069.

409 Engine Mr Gasket 1270 Oil Filter 10/26

21 The Mr. Gasket 1270 oil filter adapter uses the original bypass, which fits into the block with a rubber seal. Use red Loctite on the two adapter bolts and do not overtighten the bolts. Also pay close attention to the bellhousing bolt in this area, as the bolt can protrude into the aluminum housing and cause a nasty oil leak.

409 Engine Pistons And Connecting Rods 11/26

22 While the block is being prepared for final assembly, the pistons and connecting rods bathe in gasoline. This helps break down the carbon buildup on the pistons and ensures the ring grooves are free of any debris after a good cleaning with a wire brush.

409 Engine Arp Rod 12/26

23 After soaking and cleaning the pistons, the next step is installing the ARP rod bolts. We sent the rods to Riverside Machine Shop to have the new bolts pressed into place. After the bolts are pressed in, the rods are resized to ensure a perfectly round surface that matches the original journal size.

409 Engine Edelbrock Performer Rpm Cylinder 13/26

24 Tune in next month to see the 409 build continue by completing the rotating assembly, installing a pair of Edelbrock Performer RPM cylinder heads and a killer Comp Cams hydraulic roller setup.


Comp Cams
Memphis, TN 38118
PerTronix Performance Products
San Dimas, CA 91773
Torrance, CA 90503


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