Stock floor Driveshaft tunnel

hilton · 11-10-2022, 05:46 PM

I have a bracket car back half I need to up grade my driveshaft right now I have a 3" driveshaft spinning my motor about 8200 RPM . Was wondering before I order a better Driveshaft what size diameter can you fit in a stock tunnel Chevelle I'm asking here because I know some superstock cars buzz them motors pretty high Thanks

SDT1DYI · 11-10-2022, 06:57 PM

Call Jason at Mark Williams. They will build you a SFI certified driveshaft, based on you supplied car data.

hilton · 11-12-2022, 12:17 PM

Thanks , The question I should have asked was what's the fattest driveshaft you can fit in a stock floor I'm pretty sure I'm gonna need a 4" driveshaft . Has anyone put a 4" shaft in a stock Chevelle tunnel . Thanks again

killintime6968 · 11-12-2022, 02:08 PM

I have run a MW 3" driveshaft in my superstock car too over 9000rpm with a stick shift. A 3.5" shaft would be more than enough and should clear with no issues.

SBillinson · 11-12-2022, 06:34 PM

Driveshaft diameter comes down to critical speed based on RPM, material and length.

As someone else suggested, you may want to call Mark Williams. There are other vendors out there that are very good but I'm sold on MW parts.

I have a MW 3.5" aluminum shaft in my super stocker turning 10,400 rpm. There's no vibration or anything that would suggest a problem. It gets hit pretty hard off the trans brake, too.

CMcAllister · 11-12-2022, 09:30 PM

Depending on how low the car sits, how high the pinion is, suspension travel and how the trans/engine is in the car, you can get into trouble on those with the height of the tunnel and crossmembers in the floor.

hilton · 11-13-2022, 08:45 PM

Thank you , I'll be calling Mark Williams

Terry Cain · 11-14-2022, 04:15 AM

FYI. You can replace tunnel (make removable) in Super Stock but not in Stock.

Run to Rund · 11-15-2022, 08:38 AM

I run a 4" MW aluminum driveshaft in an Olds F85. I cut the lede extensions off the seat belt bolts for more clearance, otherwise had good clearance.

11-10-2022, 05:46 PM	#1
hilton Junior Member Join Date: Aug 2009 Location: Staten Island N.Y. Posts: 73 Likes: 97 Liked 13 Times in 6 Posts	Stock floor Driveshaft tunnel I have a bracket car back half I need to up grade my driveshaft right now I have a 3" driveshaft spinning my motor about 8200 RPM . Was wondering before I order a better Driveshaft what size diameter can you fit in a stock tunnel Chevelle I'm asking here because I know some superstock cars buzz them motors pretty high Thanks

11-10-2022, 06:57 PM	#2
SDT1DYI Member Join Date: Nov 2016 Location: Indianola Washington Posts: 356 Likes: 0 Liked 394 Times in 124 Posts	Re: Stock floor Driveshaft tunnel Call Jason at Mark Williams. They will build you a SFI certified driveshaft, based on you supplied car data.

11-12-2022, 12:17 PM	#3
hilton Junior Member Join Date: Aug 2009 Location: Staten Island N.Y. Posts: 73 Likes: 97 Liked 13 Times in 6 Posts	Re: Stock floor Driveshaft tunnel Thanks , The question I should have asked was what's the fattest driveshaft you can fit in a stock floor I'm pretty sure I'm gonna need a 4" driveshaft . Has anyone put a 4" shaft in a stock Chevelle tunnel . Thanks again

11-12-2022, 02:08 PM	#4
killintime6968 Member Join Date: Oct 2009 Location: Whitecourt,Alberta,Canada Posts: 226 Likes: 3,818 Liked 41 Times in 24 Posts	Re: Stock floor Driveshaft tunnel I have run a MW 3" driveshaft in my superstock car too over 9000rpm with a stick shift. A 3.5" shaft would be more than enough and should clear with no issues. __________________ Bruce Cameron 68 Nova 396 E/S 68 Camaro SS/? ex Checkmate Modified

11-12-2022, 06:34 PM	#5
SBillinson Junior Member Join Date: Jan 2004 Posts: 87 Likes: 39 Liked 167 Times in 47 Posts	Re: Stock floor Driveshaft tunnel Driveshaft diameter comes down to critical speed based on RPM, material and length. As someone else suggested, you may want to call Mark Williams. There are other vendors out there that are very good but I'm sold on MW parts. I have a MW 3.5" aluminum shaft in my super stocker turning 10,400 rpm. There's no vibration or anything that would suggest a problem. It gets hit pretty hard off the trans brake, too. __________________ SS/BS 1921

11-12-2022, 09:30 PM	#6
CMcAllister Senior Member Join Date: Sep 2006 Location: Fulton County, PA Posts: 533 Likes: 9 Liked 746 Times in 206 Posts	Re: Stock floor Driveshaft tunnel Depending on how low the car sits, how high the pinion is, suspension travel and how the trans/engine is in the car, you can get into trouble on those with the height of the tunnel and crossmembers in the floor.

11-13-2022, 08:45 PM	#7
hilton Junior Member Join Date: Aug 2009 Location: Staten Island N.Y. Posts: 73 Likes: 97 Liked 13 Times in 6 Posts	Re: Stock floor Driveshaft tunnel Thank you , I'll be calling Mark Williams

11-14-2022, 04:15 AM	#8
Terry Cain Senior Member Join Date: Feb 2008 Location: Georgetown, Indiana (close to Louisville, KY) Posts: 760 Likes: 492 Liked 224 Times in 103 Posts	Re: Stock floor Driveshaft tunnel FYI. You can replace tunnel (make removable) in Super Stock but not in Stock. __________________ Terry Cain ???? STK tcain@twc.com

11-15-2022, 08:38 AM	#9
Run to Rund Senior Member Join Date: Sep 2007 Posts: 574 Likes: 6 Liked 44 Times in 22 Posts	Re: Stock floor Driveshaft tunnel I run a 4" MW aluminum driveshaft in an Olds F85. I cut the lede extensions off the seat belt bolts for more clearance, otherwise had good clearance.