Go Back   Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > General Tech
GL4x4 Live! GL4x4 Casino







Search
Reply
 
Thread Tools
Old February 8th, 2006, 07:58 AM   #1
clarkstoncracker
lol
 
clarkstoncracker's Avatar
 
Join Date: 11-03-05
Location: OC - MI
Posts: 42,292
iTrader: (39)
Mentioned: 72 Post(s)
Send a message via AIM to clarkstoncracker
Default Are these RPMS on a V8 off? What is driveable?

if I were to run a th400/th350, I will have 3102 RPMS @ 70mph.

If I were to run a 700R4, I would be at 2108 RPMS @ 70mph...


I've never messed with a 700R4, is it any difference in hooking it up?
__________________
clarkstoncracker is offline   Reply With Quote
Old February 8th, 2006, 08:22 AM   #2
KILLER"B"468
Yankabilly
 
KILLER"B"468's Avatar
 
Join Date: 11-06-05
Location: Hendersonville Tn.
Posts: 7,945
iTrader: (19)
Mentioned: 1 Post(s)
Default

You will need to have the TV cable hooked up for the 700r4. and you will need to have a brake switch for the lock up. Unless you convert to 4th gear lockup up Hydraulically. Or go to a manual vale body "TCI" makes a good one for that trans. To run the 700r4 you can also get a shortend output shaft from advanced adapters. This allow you to have the same output length as a T-350.
__________________
being on the eastern edge of the central time zone sucks...it gets dark WAY to early.

Quote:
Originally Posted by jeepbrattt View Post
An occasional jello or vasoline wrestling match isn't out of the question either.
KILLER"B"468 is offline   Reply With Quote
Old February 8th, 2006, 08:57 AM   #3
Haggar
Covered in mud...
 
Haggar's Avatar
 
Join Date: 11-06-05
Location: Oxford, MI
Posts: 17,552
iTrader: (54)
Mentioned: 1 Post(s)
Default

Those seem slightly off, depends I guess. I've seen the 70R4 listed as 0.70, and sometimes 0.69 for 4th gear.

those nubmers make it about a 0.675 4th gear which I think is wrong.


That looks like, what 37" tires and 4.56 axle gears? Um, on those tires, you will NOT be wanting to go 70mph, I wouldn't worry to much about that.

55-60 mph should be your safe reasonable top speed. In that case, you will be good, running 2400-2620 rpm with 4.56s and your small block, I think. I.E. just with a TH350. At 60mph, a 700R4 would put you at 1800 rpm, might be getting a bit bogged down.


With that setup, 2nd gear will be your primary mud/sand/hill climb gear. That will be the gear you spend most of your time in. As long as your motor is healthy, that should be a pretty decent gearing for 2nd. For a manula, I'd go a little deeper, but you'll get some slip through the converter which should make up for it.

Last edited by Haggar; February 8th, 2006 at 11:07 AM.
Haggar is offline   Reply With Quote
Old February 8th, 2006, 11:07 AM   #4
Haggar
Covered in mud...
 
Haggar's Avatar
 
Join Date: 11-06-05
Location: Oxford, MI
Posts: 17,552
iTrader: (54)
Mentioned: 1 Post(s)
Default

The big thing for driveability, is think how much you will drive this jeep, and at what speeds. 37 boggers is a bit different than 33s or 35s.

Modern engines don't really mind spinning at 3000 rpm all day. Even if you take 25% off the life of the engine, is that really a concern for you?

I know when I was working landscape, the cube van I was driving was a chevy, with a 350, th350, and a 4.10 rear. We were spinning about 3300 rpm on the freeway every day.

My Jeeps/trucks/wheelers, my main concern is what my 4 wheeling gears will be. I have a pretty good idea what kind of gearing I want for the gears I will be doing most of my 4 wheeling in - think of the mounds, etc, what gears you use. Then having a gear or two lower than that for crawling and a gear or two high than that for faster speeds between obstacles. Not terribly convenient, but you can always shift back up to 4-hi if you need it.

For on road driveability, as long as I can get to 60 mph tops, I'm happy. On smaller jeeps like my TJs and my current XJ, I'd go up to 75 mph, above that, I don't really like it.
Haggar is offline   Reply With Quote
Old February 10th, 2006, 12:53 AM   #5
Mclovin
"The Situation"
 
Mclovin's Avatar
 
Join Date: 11-07-05
Location: Westland, Mi
Posts: 14,392
iTrader: (15)
Mentioned: 0 Post(s)
Send a message via AIM to Mclovin Send a message via Yahoo to Mclovin
Default

I have a 700R4 with a 350 TBi and a 3.42 R&P with 31's i run aprox. 2500 at 70
Mclovin is offline   Reply With Quote
Old February 10th, 2006, 07:19 AM   #6
Haggar
Covered in mud...
 
Haggar's Avatar
 
Join Date: 11-06-05
Location: Oxford, MI
Posts: 17,552
iTrader: (54)
Mentioned: 1 Post(s)
Default

Then you aren't kicking into 4th gear..

@ 70 mph:

3rd gear should be ~2700, 4th gear would be ~1900...
Haggar is offline   Reply With Quote
Old February 10th, 2006, 07:26 AM   #7
wrath
Project Antitube
 
wrath's Avatar
 
Join Date: 11-09-05
Location: Chelsea, MI
Posts: 450
iTrader: (2)
Mentioned: 0 Post(s)
Send a message via AIM to wrath
Default

Quote:
Originally Posted by clarkstoncracker
if I were to run a th400/th350, I will have 3102 RPMS @ 70mph.

If I were to run a 700R4, I would be at 2108 RPMS @ 70mph...


I've never messed with a 700R4, is it any difference in hooking it up?

As long as there is a load on the motor then it won't care if it is spinning 3,000rpm. I ran the motor in my truck at 4,100 on the expressway for 2 hours because there was a head wind and I had a bunch of crap in it with little tires. Didn't hurt gas mileage either since the motor was actually at a RPM that it had high efficiency.

The only thing I don't like about high RPMs is listening to the exhaust.

I wouldn't like running a motor at 3,000rpm if it had no load on it though. It's hard on reciprocating parts to have no load on it.


I like 700R4s because of the low first gear. I don't think I'd run one with tires bigger than 35s unless it had a full manual valvebody so the line pressures stayed high.
wrath is offline   Reply With Quote
Reply
Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > General Tech
Thread Tools

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 -5. The time now is 02:11 PM.


Powered by: vBulletin, Copyright 2000 - 2012, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
Copyright 2005 - 2012 Cracker Enterprises - Powered by Linux
vB Ad Management by =RedTyger=
Page generated in 0.10533 seconds with 24 queries