Anyone running a 1600/4sp with 3.7 diff?

General topics.

Moderators: garth, notoptoy, S Allen

User avatar
itsa68
Roadsteraholic
Posts: 771
Joined: Sun Apr 18, 2004 11:24 am
Location: Winnipeg, Manitoba,Canada
Model: 1500/1600
Year: High Windshield-68-70

Anyone running a 1600/4sp with 3.7 diff?

Post by itsa68 »

Currently running the stock 3.9 diff combined with 195/65 R14 tires. (Tire diameter pretty darn close to stock diameter)

Thinking of possibly switching over to a 3.7 diff on my 1600 with a 4 speed, I'm but reluctant if there is problem with diving in the hills or mountains.

(Found the gear calculator in the wiki, so I'll get on idea of rpm change.)

I'm curious what the owners that are currently running the 1600/4spd 3.7 diff set are experiencing in drive-ability on different road grades.
Comments anyone?

Cheers
Ray B.
Thats not a R16 death rattle....its a dried leaf hitting my heater blower fan.
1968 SPL311 non-smog

JT68
Talented Enthusiast
Posts: 2067
Joined: Sun Jan 27, 2013 9:43 am
Location: Cumming, GA

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by JT68 »

Its a nice combination. Corrects a bit for the VW ratio 1st gear and drops the highway revs. You won't be winning stoplight drag races, but definitely makes the 4speed more highway friendly. Give it a try, you will probably like it.
JT/LT
Datsunrestorationproducts.com
The very finest parts for your 311!

david premo
Roadster Nut-Site Supporter
Posts: 238
Joined: Wed Jan 24, 2007 8:23 am

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by david premo »

I have recommended this a bunch of times to 1600 owners. Nissan got the gear ratios backwards, both cars are better off trading differentials. Also everyone that has done this has been happy with the change.
Dave

User avatar
Curtis
Site Supporter
Posts: 2866
Joined: Fri Jan 01, 2010 2:49 pm
Location: Des Moines, WA
Model: 1500/1600
Year: Low Windshield-64-67.5

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by Curtis »

david premo wrote:
Thu May 21, 2020 9:42 pm
I have recommended this a bunch of times to 1600 owners. Nissan got the gear ratios backwards, both cars are better off trading differentials. Also everyone that has done this has been happy with the change.
Dave
Well of course since I have now had both my 3.9s overhauled. I'm putting a 5 speed in the one, maybe both.
66 stroker
67 basket case, the renewal has begun.

User avatar
redroadster
Roadsteraholic
Posts: 1331
Joined: Tue Mar 12, 2013 10:58 am
Location: KCMO

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by redroadster »

Yeah all manuf's gear too low ratio diff it to keep the cars driving .very fast and racy gets more tickets &crashes then its too $$$to insure to drive
3 .7 still to low 3.54 or even 3.0 is what I want
Steep hills arent fun on a any stick real quick
3.7 s are not easy to find Id bet , most likely came on flat terrain states AZ. FLA.

JT68
Talented Enthusiast
Posts: 2067
Joined: Sun Jan 27, 2013 9:43 am
Location: Cumming, GA

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by JT68 »

3.7 came stock in 2L.
JT/LT
Datsunrestorationproducts.com
The very finest parts for your 311!

User avatar
jhayden
Site Supporter
Posts: 228
Joined: Tue Oct 25, 2011 4:16 pm
Location: Tyler, TX

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by jhayden »

redroadster wrote:
Fri May 22, 2020 6:05 am
3.7 s are not easy to find Id bet , most likely came on flat terrain states AZ. FLA.
Better not bet too much on that: 3.7 was the stock ratio for 2000s delivered to USA, and show up regularly on eBay.

https://www.ebay.com/itm/Datsun-Roadste ... SwarNevUv9

Jon

User avatar
Daryl Smith
Roadster Fanatic-Site Supporter
Posts: 1363
Joined: Wed Sep 08, 2004 1:53 pm
Location: Vancouver, BC, Canada
Model: 1500/1600
Year: Low Windshield-64-67.5

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by Daryl Smith »

"Its a nice combination. "
x4

As JT says.
I've recommended it myself. Did it on my old 1600. Never a problem.
Most likely you will hardly notice except for a couple hundred rpm down on the highway, maybe less (on stock size tires or near stock). In the lower gears you will hardly notice it at all.
Daryl
'66 2065cc Stroker "Frankie", EFI and GM D585 ignition
she aint pretty, she just looks that way...
http://www.311s.org/registry/1966/spl311-01605.html

User avatar
Alvin
Roadster Enthusiast
Posts: 7583
Joined: Tue Jan 23, 2007 7:01 pm

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by Alvin »

Count me in too! It's nice if you want more "relaxed" cruising rpms...no noticeable deficits otherwise.
I will add that 1600s with the stock 3.9 just sing along at "high rpms" on the freeway...personally never had a problem with it.

Also... the R16/3.9/5-speed combo is great.
Alvin Gogineni
San Jose, CA
1967.5 SPL/SR20
1997 Acura Integra GS-R
2013 Prius V wagon
zcarblog.com
Instagram
YouTube
My SR20 Build Thread

User avatar
redroadster
Roadsteraholic
Posts: 1331
Joined: Tue Mar 12, 2013 10:58 am
Location: KCMO

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by redroadster »

jhayden wrote:
Fri May 22, 2020 8:14 am
redroadster wrote:
Fri May 22, 2020 6:05 am
3.7 s are not easy to find Id bet , most likely came on flat terrain states AZ. FLA.
Better not bet too much on that: 3.7 was the stock ratio for 2000s delivered to USA, and show up regularly on eBay.

https://www.ebay.com/itm/Datsun-Roadste ... SwarNevUv9

Jon
Maybe just here ...in the last 12 years of searching CL
I remember 2 or 3 2 L 311s. .unless it was in the 7500 up range ..I searched for 2 yrs looking for mine found only 1 that was worn out as hell for 3800$

User avatar
notoptoy
Vendor-Site Supporter
Posts: 9255
Joined: Fri Oct 02, 2009 2:55 pm
Location: Winston-Salem, NC and Ocala, FL

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by notoptoy »

Alvin wrote:
Fri May 22, 2020 9:00 pm
Count me in too! It's nice if you want more "relaxed" cruising rpms...no noticeable deficits otherwise.
I will add that 1600s with the stock 3.9 just sing along at "high rpms" on the freeway...personally never had a problem with it.

Also... the R16/3.9/5-speed combo is great.
Agreed:
I had the 4 speed 3.9 and drove it across country no problems, but the drone does get too you after5-6 hours. The entire time, my buddy and I would comment on how nice it would be to have a 5-speed and the car really seemed to need it. I REALLY would have enjoyed the lower noise of a 5 speed. So, I now have the H20/3.9/5-speed and agree, it is a great combo.
"When all else fails, force prevails!" Ummm, we're gonna need a bigger hammer here.

67.5 SPL311 H20 w/5 speed
65 Impala Convertible
2017 C43 AMG

Dano
Roadster Fanatic
Posts: 122
Joined: Fri Dec 27, 2013 4:11 pm
Location: Mill Valley California
Model: 2000
Year: Low Windshield-64-67.5

Re: Anyone running a 1600/4sp with 3.7 diff?

Post by Dano »

I just added3.7 To my 1970 1600 last month. I love it. I notice it on the freeway. It’s a fantastic upgrade. I still have the original 4 speed in it.
Smoke em if you got em! :smt025

1967.5 2000 SRL311-00438
1968 SPL KA24DE (sold)
1969 SRL (sold)
1970 SPL 1600 Bone stock and beautiful
2006 Lotus Elise Supercharged