The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 03-02-2004, 11:59 AM   #1
flip66
Registered User
 
flip66's Avatar
 
Join Date: Jan 2004
Location: Garland TX Dallas area
Posts: 658
What gears are you running

I am not sure what gears I have but I have a set of 3:73 I was thinking of using. I was talking to someone that has 3:73 and he said when he's going about 60 MPH he is turning about 3000 RPM. He has a 350 with a 350 trans I have a 396 with a 400 trans. I can run at 70 MPH and run at about 3000 this leads me to believe I may have 3:08 but again I am not sure what my gears are.

Can any of you guys out there tell me what RPM you are running at 60 MPH and what gears you have.
flip66 is offline   Reply With Quote
Old 03-02-2004, 12:08 PM   #2
Oborny71
Registered User
 
Oborny71's Avatar
 
Join Date: Apr 2001
Location: Lincoln, Nebraska
Posts: 587
here you go.

http://www.smokemup.com/auto_math/rear_end.php
__________________
67 Chevy SWB - goal of a 1,000 hp weekend cruiser
Oborny71 is offline   Reply With Quote
Old 03-02-2004, 12:09 PM   #3
Oborny71
Registered User
 
Oborny71's Avatar
 
Join Date: Apr 2001
Location: Lincoln, Nebraska
Posts: 587
sorry , i guess you need to be registered to that site. worth doing though. they have very good auto math calculators.
__________________
67 Chevy SWB - goal of a 1,000 hp weekend cruiser
Oborny71 is offline   Reply With Quote
Old 03-02-2004, 12:13 PM   #4
70cst
Senior Member
 
70cst's Avatar
 
Join Date: Feb 2001
Location: New Madison, Ohio
Posts: 21,373
Hey Flip66...
My 70cst has a factory 402BB with the 400 tranny...the stock rear end was a 3:08 and I have installed a 3:41 (?) posi. I'm not sure what rev's I'm running. Next time I get her out I'll check out the RPM's.
Regards,
70cst
70cst is offline   Reply With Quote
Old 03-02-2004, 12:20 PM   #5
Bill72BB
Thats the Hillbilly way
 
Bill72BB's Avatar
 
Join Date: Jul 2001
Location: Torrance,Ca
Posts: 5,979
Here is a site that may help.

http://richmondgear.com/streetcalculators.html

I'm running 3.54 with 32.5" tires
__________________
BILL
Torrance Calif 90504
Member DUF Club
Member Old Farts Club
72 3/4ton Custom Camper BB402/400 trans Dynomax Cerama-coat headers , Hei distributor ,Edelbrock 1411 air,ps,pb,leafsprings ,98 chevy 60/40 seat,S10 shoulder belts
tilt,3.54 Dana 60 rear. 16" Eagle wheels with LT265/75 16 tires,Gaylord Lid,H4 headlights with 100W relay conversion.


" If I knew I was going to live this long I would have taken better care of myself "
Marriage changes passion...suddenly you're in bed with a relative. A GUY'S PRAYER....

Lord, I pray for a nympho with huge boobs who owns a liquor store and likes to fish and hunt and has a Harley .Amen ,
Bill72BB is offline   Reply With Quote
Old 03-02-2004, 12:32 PM   #6
SWEET7T
Try spinnin 4 rear tars
 
SWEET7T's Avatar
 
Join Date: Sep 2003
Location: Salt Lake City, Utah
Posts: 757
I have 3.08's from the factory and I'm turning 3g's at ~80.

Flip, your going too slow to have 3.08s, sounds more like 3.54 or (were 3.31's offered in these trucks?!?! )
__________________
SWEET7T
1970 C10, 2wd, LB, 307/TH350/3.08. PS, PB
SWEET7T is offline   Reply With Quote
Old 03-02-2004, 12:34 PM   #7
Bowtie67
Registered User
 
Bowtie67's Avatar
 
Join Date: Jan 2004
Location: NH
Posts: 2,266
Post

plug in the numbers and you should get a good idea..


http://www.angelfire.com/fl/procrastination/rear.html


Bowtie67 is offline   Reply With Quote
Old 03-02-2004, 02:16 PM   #8
Yellow Cheyenne
Registered User
 
Join Date: Jun 2001
Location: Eastern Kansas
Posts: 488
In my '96 that has 3.42 ratio I am running about 2800 to 2900 RPM at 70 MPH when in drive. I am running 235/75/15 tires.

Randy
__________________
'72 Cheyenne. AC, PS, PB, Rear slider window, tilt. Light yellow (grapefruit yellow according to new sales literature from '72)
'56 Chevy short step V-8 (My dad bought it new!!)
'70 Olds 442 convertible
'70 Olds Rallye 350
Yellow Cheyenne is offline   Reply With Quote
Old 03-02-2004, 03:00 PM   #9
flip66
Registered User
 
flip66's Avatar
 
Join Date: Jan 2004
Location: Garland TX Dallas area
Posts: 658
Thanks guys I have to make sure on the RPM but it looks like they may 3:73 already.
flip66 is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 05:49 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com