|
Register or Log In To remove these advertisements. |
|
|
|
|||||||
 |
|
|
Thread Tools | Display Modes |
04-05-2002, 07:46 PM
|
#1 |
|
Registered User
 
Join Date: Oct 2001
Location: Southern New Mexico
Posts: 649
|
3K RPM's Get's Me 70 MPH What Do U Get?
3000 RPM's Get's Me 70 MPH What Do You Get?
TH400 350. Do I need the tire size to find out what gears are in the rear end? I sure would like to be in the 1700 range at 70 MPH. Maybe a 700r Tranny? Lets here it Eric |
|
|
|
04-05-2002, 07:53 PM
|
#2 |
|
Senior Member
 
Join Date: Dec 1999
Location: Darrington, Washington
Posts: 3,963
|
My 402 turn at about 3200rpm on the freeway at the legal posted 75 speed limit.According to the code on my axel i have 3.08 gears,my tirs are 31x10.50 15's.seems hi to me,maybe the factory tach is off,i hope.I wouldnt care if it was a 283 or something a smallblock doesnt mind the rpms much,but big blocks dont like hi-rpm-a little hard on them after a while.
|
|
|
|
|
04-05-2002, 08:04 PM
|
#3 |
|
"Ochre Ogre"
Join Date: Apr 2000
Location: Springfield, MN
Posts: 3,558
|
You need the tire size to figure this out. Take a look here when you have the information. You should be able to plug in the numbers on the rpm calculator. http://www.ring-pinion.com/
__________________
Bowtie Truck Stop Inc. Mid-West GM Truck Restoration Parts Supplier Your Key Parts, Auto Metal Direct, Dynacorn, and Goodmark dealer. like us @ www.facebook.com/BowtieTruckStop 1971 C-10 Suburban (Ochre) 1971 K-10 Suburban (Ochre) 1972 C-10 Suburban (Ochre) 1972 K-20 Suburban (Yellow- that just aint right!) Springfield, Minnesota 56087 |
|
|
|
|
04-05-2002, 08:44 PM
|
#4 |
|
Senior Member
Join Date: Dec 2000
Location: Indiana
Posts: 3,074
|
I turn 2400 at 75
------------------
__________________
71 Chevy CST Long Fleet 350/350/3.07 leaf rear. |
|
|
|
|
04-05-2002, 08:55 PM
|
#5 |
|
Senior Member
Join Date: Dec 1999
Location: Darrington, Washington
Posts: 3,963
|
Next truck i build i have a 468 going into a 67 SWB project and id like to put in a 700R4,love to loaf along the freeway at 125 mph at 2000 rpm and get 20mpg,awaking from my dream,now.hey i can wish.I think a fuel injected,468 ci motor, over 500hp and 20 mpg would be sweet,7-10 mpg sucks even in a cruiser when you got $10 in your pocket and you still need to buy some beer,and tanks on E.its called 2 gallons of gas,and a bunch of cheapy malt liqour 40oz ers.or a nasty $7 bottom of the shelf 5th of whiskey.
|
|
|
|
|
04-05-2002, 09:11 PM
|
#6 |
|
Registered User
Join Date: Aug 2001
Location: rock island,il,usa
Posts: 5,382
|
3000 rpms @ 60 mph.....4.10 coggs on a 28" tire. FUN!.....69 longhorn.
__________________
http://community.webshots.com/user/hotrodhorn |
|
|
|
|
04-05-2002, 09:14 PM
|
#7 |
|
Account Suspended
Join Date: May 2000
Location: IL
Posts: 0
|
lol desert rat
|
|
|
|
|
04-05-2002, 09:19 PM
|
#8 |
|
4:13
Join Date: Dec 1999
Location: St. Cloud, Florida
Posts: 500
|
I get 2500 at 50,about 3000 around 60 and right at 3500 to 3750 at 70.I am running a
350/350 with 275/60-15's on the rear.That 700r sure looks good sitting in the garage, Can' wait till it is between the frame rails! ------------------ '72 longbed,350\350,4\6 drop,p.s,p.b,tach. http://hometown.aol.com/rp2bp/myhomepage/auto.html |
|
|
|
|
04-05-2002, 09:30 PM
|
#9 |
|
Formerly yellow72custom
Join Date: May 2001
Location: Austin, TX
Posts: 7,531
|
3000 rpm's gets me roughly 75 mph. 3.07 rear gears, and 255x60-15 tires. I hope to upgrade to a 700R4, and i may keep the high gears. Then i will be praticly idling at 75
 . I heard somewhere that the 700r4 won't cruise at high speeds in OD because the tranny will kick down at 2/3 throttle. Is this true, and if so is there a way to get it to stay in OD at full throttle? I dont wanna drive too fast, but a run up to 130+ sure would be fun .------------------ Lucas "Another proud owner of one of the coolest trucks ever built" drop_shift@hotmail.com My Daily-Driver: '72 Chevy LWB Custom/10. Rebuilt 350, 300 HP thanks to a few go-fast goodies. Ochre with a white top. Future plans include TBI fuel injection, a 700R4 tranny, and possibly some 3.73 rear gears.
__________________
'72 Chevy C10 Mild 350/TH350/3.07. Ochre/White. Old high school ride. '70 GMC C2500 '62 327 4bbl/SM465/4.56-geared Dana 60. White/White. Project or parts truck. '97 Saturn SL DD. 1.9/5-speed. 40+ highway mpg |
|
|
|
|
04-05-2002, 10:16 PM
|
#10 |
|
its all about the +6 inches
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,690
|
Jeggs carries the part you need for that. Still won't run full throttle, but it'll cruise at 3/4 throttle in 4th
------------------ '69 G.M.C. 350/350. Trying to clean up the left over damage from the Dope-Smokin-Old-Man I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it. FINALLY got the HORNIAC...a '70 one ton Longhorn with a Pontiac 350/350 and lots of 'personality'. Check out The Longhorn Webite. If you need a pic posted, E-mail me at longhornmail@yahoo.com Andy, in Columbus Ohio |
|
|
|
|
04-06-2002, 02:40 AM
|
#11 |
|
Senior Member
Join Date: Jun 2000
Location: yucaipa ca
Posts: 580
|
2000 rpm at 75. 3.73 gear with a t5 tranny.
|
|
|
|
|
04-06-2002, 02:51 AM
|
#12 |
|
Registered User
Join Date: Oct 2001
Location: Southern New Mexico
Posts: 649
|
Well, after a bit of cypherin I have the ratio at 3.82. Sound about right?
I cant tell if the tire is 30 or 30.5 Eric |
|
|
|
|
04-06-2002, 07:35 AM
|
#13 |
|
Registered User
Join Date: Jan 2002
Location: Fayette, Alabama
Posts: 155
|
Hey Desert Rat sounds like your factory tach is the problem!!! I'll take that defective piece of equipment off your hands. I'll even pat postage. lol.
__________________
Fayette Alabama |
|
|
|
|
04-06-2002, 08:24 AM
|
#14 |
|
Senior Member
Join Date: Jun 2001
Location: Shelbyville, KY
Posts: 3,261
|
3,000rpm gives me 80+MPH. 308rear--96 1/2 ton 5speed, 235x75R15 rubber. 20+mpg on the flats. If towing, downshift to 4th on bigger hills. GOT to love that 5 speed!!
By the way, hear tell that our factory Tachs do not read true if using HEI ignition (heard/read on ColoradoK5). The tachs read higher then reality!? ------------------ 72 Cheyenne, 350, 5spd, LWB, Super trim. 71 GMC JIMMY 4X4 --needs stuff-! |
|
|
|
|
04-06-2002, 08:28 AM
|
#15 |
|
Senior Member
Join Date: Dec 2000
Location: Indiana
Posts: 3,074
|
Our factory tachs can be recalibrated. I calibrated my factory 6 cyl tach to a aftermarket tach for my V8 with HEI. Works perfect.
Sounds like you read some bad info. ------------------
[This message has been edited by 71Chev (edited April 06, 2002).]
__________________
71 Chevy CST Long Fleet 350/350/3.07 leaf rear. |
|
|
|
|
04-06-2002, 11:58 AM
|
#16 |
|
Registered User
Join Date: Apr 2001
Location: DALLAS,TX
Posts: 22,068
|
60mph @ 3000rpm w/stock 3spd manual & 3.73's w/275/60/15's. 12-13mpg on the open road w/a friggin' 6 banger/1 barrel sucks. From Dallas to Houston or Tulsa, OK: 1 tank gas/1 qt oil there, same coming back. Sounds like a candidate for o.d. huh?
__________________
67SWB-B.B.RetroRod 64SWB-Recycle 89CCDually-Driver/Tow Truck 99CCSWB Driver All Fleetsides @rattlecankustoms in IG Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive. It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar..... Cubic inches is like Indiana Jones with a cheap pistol. |
|
|
|
|
04-06-2002, 12:46 PM
|
#17 |
|
Registered User
Join Date: Feb 2001
Location: East Central, MO
Posts: 11,336
|
2700 rpm's=125db's yeah louder than a jet. Hookers, Supertaps, and 35x15.50 super swampers. And we'd be rollin!
------------------ 67 stepside 4x4 Owensville MO mudder67@hotmail.com |
|
|
|
|
04-08-2002, 09:06 AM
|
#18 |
|
Junior Member
Join Date: Sep 2001
Location: Phx,Az USA
Posts: 67
|
I just did the 700r change over thanks to Bowtie overdrives & I went from a 350ci/T400 w/ 3.73 rear that got 3000 rpm=70 on 31x15 tires to now I have the same engine/rear/tires but only 2000rpm @ 70...man I can't tell you how much I love the new trans. The Bowtie folks where way cool (www.700r4.com ??? or www.bowtieoverdrives.com) I got everything except the crossmember (next time I would order that also) and no core charge. All went in smooth & after the pressure test & the over the phone walk through I now am shifting harder than before (and the T400 is a B&M factory built unit...anyone want it???) and the mileage is way better.
Anyway I love the 700r and would never go back. 1 Leg Lance |
|
|
|
|
04-08-2002, 09:14 AM
|
#19 |
|
Senior Moment
Join Date: Mar 2002
Location: Pittsburg Ca
Posts: 4,192
|
1 leg. I cant get to the bowtie site is it correct? What do you want for the 400?
__________________
1970 CST LS 1 6 speed Ford 9 inch Detroit Tru Track, Dakota Didgital, Vintage Air, QA1 Coil Overs Front & Rear Lots of FUN 2013 GMC PU, Oldest Son 71 GMC LWB. QA1 Suspension, Angry SB. Youngest Son 2017 Toyota SUV Daughters car 2018 Traverse , Wife’s Ride Pittsburg Ca 94565 |
|
|
|
|
04-08-2002, 09:28 AM
|
#20 |
|
Keepin' It Stock
Join Date: Aug 2001
Location: Grand Island, Nebraska, USA
Posts: 554
|
here's the site --
http://www.bowtieoverdrives.com ------------------ 72 Sierra Grande - "Maych" sierraG on some boards If a man speaks in the middle of a forest and there is no woman around to hear him, is he still wrong? Forget about "do it right the first time". Do it wrong the first time to learn how, then do it right the second time. Maych Home Page
__________________
72 Sierra Grande - Maych Forget about "do it right the first time". Do it wrong the first time to learn how, then do it right the second time. |
|
|
|
|
04-08-2002, 10:11 AM
|
#21 |
|
Registered User
Join Date: Feb 2000
Location: Maquoketa, Ia/ Orr, Mn
Posts: 3,052
|
I run about 2300 at 70mph with a 350/th350, 3:08 Posi and 35" tires. Would like to run 4:10's some day.
__________________
'51 South Bend Model "9A" '56 Chevy 3600 NAPCO '74 Chevy Cheyenne Super K20-restored on 37's '72 GMC Sierra Custom K2500- in progress '08 GMC Envoy Denali '12 GMC Sierra 2500HD Denali '17 GMC Yukon XL VCCA member #58596 http://www.nohrco.com |
|
|
|
|
04-08-2002, 10:43 AM
|
#22 |
|
user # 2756
Join Date: Jun 2001
Location: Chesapeake, Virginia
Posts: 4,612
|
I get 65 MPH at 3000 RPMs, with 325/60R15 BFGs(31-12.5 equivalent) and 4.10 gears.
------------------ 1970 GMC K25 Custom Chesapeake, VA My 70 GMCor Webshots http://community.webshots.com/user/70gmc
__________________
1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs 1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX 1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears 1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now..... 1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone. 1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed. 1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm 
|
|
|
|
|
04-10-2002, 11:44 AM
|
#23 |
|
Registered User
Join Date: Apr 2000
Location: Freeland,Michigan,USA
Posts: 312
|
60 mph=1800 rpm for me
__________________
1968 SWB Stepside, 250,pwr disc brake and tilt pwr steering, 5 spd tranny, HEI,Accel coil,K&N filter,Seat from a later truck with built in seatbelts, front and rear sway bars, moved gas tank to under the bed, headman hedders, new chrome bumpers,one wire alternator,Weber k550cub carburator...WORK IN PROGRESS, Freeland MI , Just bought a 72 Jimmy!!!!!!!!!!! |
|
|
|
|
02-04-2021, 03:11 PM
|
#24 |
|
Registered User
Join Date: Mar 2006
Location: Malvern, PA
Posts: 951
|
Re: 3K RPM's Get's Me 70 MPH What Do U Get?
Reviving an old thread here...
These RPMs @ MPH being reported are much lower than I expected. 72' Blazer: 3,500 RPM at 60 MPH with a 350/TH350 and 33" tires. I don't know what the gear ratio is but if I had guess, it's 4:56 or 4:88. BTW- for folks trying to what gear ratio to choose if changing tire size, I found this informative clip on youtube. https://www.youtube.com/watch?v=oDVpyhKEbaw
__________________
Photo Gallery of 1972 K/5 Blazer CST |
|
|
|
|
02-04-2021, 03:24 PM
|
#25 |
|
Registered User
Join Date: Aug 2009
Location: Bowser
Posts: 13,735
|
Re: 3K RPM's Get's Me 70 MPH What Do U Get?
Punching numbers in here says 5.72 gear.
Could be tach is wrong or excessive slippage in convertor. http://www.advanced-ev.com/Calculators/TireSize/ |
|
|
|
|
| Bookmarks |
|
|
Linear Mode
