This is one of those topics that has actually been discussed so much that searching can result in enough unrelated information that the good stuff is lost in the mix. So here's just a very quick mention of a few possible upgrades for your SBC starter using factory parts, although I'm sure there are more.
If your factory low performance starter is causing you trouble, look into part number 6449 for a 168 tooth flywheel or 6470 for 153 tooth (or even 6492/ 6494). If you're unsure which style you have check how yours mounts: starter bolt holes that are staggered indicate you have a 168 tooth flywheel/ flexplate, and if they're straight across from each other you have a 153 tooth flywheel/ flexplate. These starters are the factory "high" performance version and are 10 lbs lighter, smaller so they clear headers better, draw fewer amps, and employ gear reduction so it cranks with more torque. They came on 4x4s, LT1s, Caprices, and a few other models and the only issue is that they're about $140 (or more) brand new. However, they can be found for $50 at salvage yards and even less if the person thinks it's just a regular starter. This is an upgrade that's extremely worth it if you're already changing the starter and you can combine it with high quality battery cables and a Ford remote solenoid for the ultimate upgrade.
The Duralast part # for 153 tooth is DL9990S. For other brands simply remove the "DL". For the 168 search 6449S. It's a 2.28hp motor.
Another cheaper option for people that want an upgrade and don't require the extra torque is the DL6416S. It's smaller than stock and weighs 6 lbs less, but is not a gear reduction starter. This is a 1.6hp motor which is the same as a good old fashioned sbc starter, and is a great choice for most engines that are running headers.
The bolts you choose are very important: The old style bolts have knurling that measures about 9.7 mm and the newer bolts that come with the "mini" starters have knurling that's 10.1 mm- too wide to properly seat into the block. But you can't just use the old bolts either, as they won't fit snugly inside the starter and will allow movement over time. You need to get the right bolts from GM and the short bolt is part # 14037733 and the long one is 12338064. The knurl by the threads which fits into the block is the same size as on the old bolt, and the knurling that fits inside the starter is larger.
Link: https://bzerob.com/library/gm/gmPMGRupgrade.html
If your factory low performance starter is causing you trouble, look into part number 6449 for a 168 tooth flywheel or 6470 for 153 tooth (or even 6492/ 6494). If you're unsure which style you have check how yours mounts: starter bolt holes that are staggered indicate you have a 168 tooth flywheel/ flexplate, and if they're straight across from each other you have a 153 tooth flywheel/ flexplate. These starters are the factory "high" performance version and are 10 lbs lighter, smaller so they clear headers better, draw fewer amps, and employ gear reduction so it cranks with more torque. They came on 4x4s, LT1s, Caprices, and a few other models and the only issue is that they're about $140 (or more) brand new. However, they can be found for $50 at salvage yards and even less if the person thinks it's just a regular starter. This is an upgrade that's extremely worth it if you're already changing the starter and you can combine it with high quality battery cables and a Ford remote solenoid for the ultimate upgrade.
The Duralast part # for 153 tooth is DL9990S. For other brands simply remove the "DL". For the 168 search 6449S. It's a 2.28hp motor.
Another cheaper option for people that want an upgrade and don't require the extra torque is the DL6416S. It's smaller than stock and weighs 6 lbs less, but is not a gear reduction starter. This is a 1.6hp motor which is the same as a good old fashioned sbc starter, and is a great choice for most engines that are running headers.
The bolts you choose are very important: The old style bolts have knurling that measures about 9.7 mm and the newer bolts that come with the "mini" starters have knurling that's 10.1 mm- too wide to properly seat into the block. But you can't just use the old bolts either, as they won't fit snugly inside the starter and will allow movement over time. You need to get the right bolts from GM and the short bolt is part # 14037733 and the long one is 12338064. The knurl by the threads which fits into the block is the same size as on the old bolt, and the knurling that fits inside the starter is larger.
Link: https://bzerob.com/library/gm/gmPMGRupgrade.html
Last edited:
