Build Thread A 1984 Black CJ7 Build - My never ending project/addiction

[diddy2003]

All wrapped up. It drives great. Plenty of power and cruises right along at 65 mph. The Transmission makes it feel like I'm driving a bus. It is a lot of fun though. I think it will just take some getting used to.

 

[CJ]

Looks great! I'm glad your enjoying your hard work!

 

[Belizean]

So do you take off in first or second when in town driving ?

 

[diddy2003]

So do you take off in first or second when in town driving ?

I only drove it home from the shop, but I did a little of both. It isn't T-18 low in first, just pretty low. I mostly started in first.

 

[diddy2003]

So do you take off in first or second when in town driving ?

I took it out yesterday. I know there is salt on the roads, but it was dry and driving it was a little early Christmas present to myself.

I did a little of both, but 1st is definitely short.

5.61:1 first gear, 4.10 axle gear, and 35s:
2000 RPM = 9 MPH
2200 RPM = 9.9 MPH
2400 RPM = 10.8 MPH
2800 RPM = 12.6 MPH

First was nice on hill departures, to play with shifting, and just casual driving. But, as you can see, its slow. I was shifting around 2000 RPM because it really makes no difference to rev it out anymore. It does kinda feel like driving a tank/school bus with the low first gear, which is also pretty fun.

For most other driving I used second. For example, leaving a side street onto a main road, another car coming, anywhere where I needed speed sooner.

3.04:1 second gear, 4.10 axle gear, and 35s:
2000 RPM = 16.7 MPH
2200 RPM = 18.3 MPH
2400 RPM = 20 MPH
2800 RPM = 23.4 MPH

Numbers are just a guess with 35s, as all these tires seem to have variables with their actually diameter size, and mine aren't brand new. Numbers were calculated with this:

Gear Ratio Calculator : POWERNATION

Use our Gear Ratio Calculator to optimize your vehicle's performance by accurately determining gear ratios, RPM, tire diameter, and MPH.

www.powernationtv.com

They did a nice build on an AMC 304 :

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[diddy2003]

Just for fun, since my friend has a T-18 , these are those numbers.

6.32:1 first gear, 4.11 axle gear, and 35s:

2000 RPM = 8 MPH
2200 RPM = 8.8 MPH
2400 RPM = 9.6 MPH
2800 RPM = 11.2 MPH

No wonder he starts in second gear all the time on the street, although it really isn't that much different than mine.

 

[Belizean]

Yeah that 1st is killer off road, but driving around not so much. I remember test driving a new 88 or 89 Bronco with 300 6 cylinder and with a 4 speed with a super low 1st gear. Figured later it was probably a T-18 . There was really no reason to start in first when driving around town. Just something you get use to, like a typical Jeep.

 

[diddy2003]

Just for comparison purposes, the T-176 the Jeep came with and I took out:

3.52:1 first gear, 4.10 axle gear, and 35s:

2000 RPM = 14.4 MPH
2200 RPM = 15.8 MPH
2400 RPM = 17.3 MPH
2800 RPM = 20.2 MPH

So basically, like my current second gear in the NV 4500.

 

[diddy2003]

Yeah that 1st is killer off road, but driving around not so much. I remember test driving a new 88 or 89 Bronco with 300 6 cylinder and with a 4 speed with a super low 1st gear. Figured later it was probably a T18. There was really no reason to start in first when driving around town. Just something you get use to, like a typical Jeep.

Yup, two friends have CJs with the T-18 . One has a 1974 CJ5 (4.11 rear gear, 3.15:1 Dana 20 with Tera Low, and 35s) and the other has a 1978 CJ7 (3.73 rear gear, 2.03:1 Stock Dana 20 , and 33s). Both basically use the T-18 as a 3 speed on the road. Now I understand why. They are like driving a tractor. My jeep kinda feels like that now, although with a lot of power and noise.