4 bolt main?

[hotrod ford]

was does the 429 have this and the 460 don't?

[convincor]

Only CJ/SCJ and Boss 429's would be 4 bolt.

[averagef250]

Many 78-79 truck 460's got them as well. There is no point to 4 bolt mains unless you're racing. Even racing they are not necessary.

[Dragon]

Needing 4 bolt mains depends on the RPM and stroke. I spun 390s to 7 grand no four bolt mains. I spun one 428 internal balance engine to 8 and broke it after 4 weekends. I built another and did the same internal balance 428 with 4 bolt mains and got 12 weeks before we found stress cracks in the main webbing. Personal choice by the builder usually but the Cheby guys really go for the 4 bolt mains. I had a 396 that spun 7000 all the time with 2 bolt mains but I had a friend that did it and warped the main saddle. I saw SBCs turning 8 and 9 and one at 10 and boy did the bottom ends go fast without the extra strength.

[rubiranch]

All stock 460 blocks have 2-bolt mains, 1970 429 CJ blocks are 2-bolt, 1971 429 CJ blocks are 4-bolt, all 429 SCJ blocks are 4-bolt.

All Boss 302s, 351s, and 429s have 4-bolt mains.

Late 1962 406s and all 427s #2,3 and 4 main caps were cross-bolted.