Good match up? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Doc Harrel · 11-10-2009, 01:36 AM

I have a bone stock 400 sbc in a 68 stepside. The truck has a 400TH tranny and 4:11 rear diff. I would like to drive it to work, about a daily 6 mile round trip, but still be able to turn some good times on the track. I was thinking about boring it out to a 406, and maybe changing the gears ratio in the diff. What kind of suggestions do you guys have? Should I leave the differential gearing alone? Should I leave the engine alone? What would you do, or what have you guys done with similar setups?

Also...what kind of peak rpm can I expect to get out of a 400? 406?

11-10-2009, 01:36 AM	#1
Doc Harrel Registered User Join Date: Feb 2009 Location: Tucson, Az Posts: 25	Good match up? I have a bone stock 400 sbc in a 68 stepside. The truck has a 400TH tranny and 4:11 rear diff. I would like to drive it to work, about a daily 6 mile round trip, but still be able to turn some good times on the track. I was thinking about boring it out to a 406, and maybe changing the gears ratio in the diff. What kind of suggestions do you guys have? Should I leave the differential gearing alone? Should I leave the engine alone? What would you do, or what have you guys done with similar setups? Also...what kind of peak rpm can I expect to get out of a 400? 406?

Thread Tools
Show Printable Version Email this Page
Display Modes
Switch to Linear Mode Switch to Hybrid Mode Threaded Mode



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.