Author Topic: Perkins 6-354 Diesel with a TH400  (Read 13063 times)

Offline tyheid2002

  • Newbie
  • Posts: 11
Perkins 6-354 Diesel with a TH400
« on: August 21, 2010, 02:26:21 PM »
All, I have a 1988 Chevy 1ton Crew Cab Dually 4x4, old body style, with a 350 and I am seriously comtemplating converting it to a diesel and putting an a Perkins 6-354, which are fairly common (cheap) in Nebraska in old Massy 750 combines. I have scoured the internet and have not been able to find much information on conversions. I know the diesels are cold blooded, but I want the power and efficiency....  ;D That being said, I have a very strong TH400 that I would like to bolt a Perkins to, does anyone know of adapters or should I get a different tranny (would like to keep it an auto)???

Or recommend some diesels that are easier to adapt and cheap...

Offline VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 18980
Re: Perkins 6-354 Diesel with a TH400
« Reply #1 on: August 21, 2010, 10:28:59 PM »
The power and efficiency? I just don't see it personally. You'll get good low endtorque but if you want power and efficiency then stick with gas and do some drivetrain upgrades. Get rid of the 400 and get an overdrive trans. Sorry if this doesn't help you
,                           ___ 
                         /  _ _ _\_
              ⌠¯¯¯¯¯'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline Blazin

  • Blazin new trails!
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6130
Re: Perkins 6-354 Diesel with a TH400
« Reply #2 on: August 22, 2010, 10:55:31 PM »
If you have to have diesel a 12 or 24 valve Cummins is the way to go. 12 valve are less power but are easier to set up in an older truck.But they can also be juiced up easily. Allot less wiring etc.
 The 24 valves have several computers etc.
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs

Offline 1HI4x4

  • Registered Users
  • *
  • Posts: 248
  • V30 Crew now a shortbed.....
Re: Perkins 6-354 Diesel with a TH400
« Reply #3 on: August 23, 2010, 05:29:13 AM »
I'm doing a 12 valve Cummins in mine, this site has lots of info on swaps.


http://www.4btswaps.com/forum/forumdisplay.php?28-Detroit-Perkins-Caterpillar


As for the power and effeciency, most diesels will make alot of torque in a reasonable RPM range, and the fuel mileage is undeniable, you consistantly see high teens and low 20 mpg in 6000-7000 lb. trucks. A very healthy BBC will make 450 ft lbs of torque at 3500 rpms, and will be at the low end of it's HP at that RPM's. This same engine in a 6000 lb truck will struggle to get 10 mpg. A 12 valve Cummins will make 450 ft. lbs of torque at 2500 RPM with just minor mods, and will get 16-20 mpg in a 6000 lb truck. Now if you don't like diesels because of the hammering and smoke that is something that can't be fixed...........  :)
1988 V30 Crew Cab, Cummins power, 47RH-NP205, 8" lift, 13.50x35x20 Fuel Mudders on 20x14 XD Diesels -76 offset. Soon to be repainted, seats from a 2010 Lariat to be installed.

Offline Edahall

  • Frequent Member
  • **
  • Posts: 311
Re: Perkins 6-354 Diesel with a TH400
« Reply #4 on: August 23, 2010, 11:33:19 AM »
This would be a cool conversion.  The Perkins is known for excellent fuel efficiency.  One issue you will run into if you use the TH400 and the 4.11 rear end your truck most likely has is a very slow top speed.  You may not even be able to hit 55 mph.  You would either need to go to a 3.08 rear end or some other type of transmission with an overdrive like a 700R4 or NV4500.  The TH400 is also a poor choice for good fuel economy if that's what you're after.  There is no lock up torque converter.  I don't know what it would take to hook up this engine to the transmissions listed but you might be able to find some information at the following link.

http://shadetreeconversions.com/

If fuel economy is what you're after, my 1990 Suburban that now has a Cummins 12 valve engine delivers 26 mpg on the highway at 65 mph.  With the gearing, the engine turns over at 1420 rpms at 65 mph.  Use a VE pump Cummins for best fuel economy.   I bet a Perkins that's geared correctly would even do better on fuel economy.
1990 ¾ ton 4x4 Chevy Suburban
-Cummins Diesel - 12 valve - factory rebuilt
-6 speed bullet proof manual transmission - NV5600
-Gear Vendors Overdrive
-Upgraded Holset HX-35 turbo
-NP205 iron transfer case
-3.73 gears
-2" Lift