I have a NA 354 perkins that is probably going into a 1973 Ford. Ive been told that the NA perkins do not come with piston cooling jets. Therefore, if I put a turbo on it, it would burn the pistons up pretty quick. However, I am not putting a turbo for more power, but rather for more economy. If anything, the diesel injector pump will be turned DOWN. So would a turbo actually hurt the engine if I don't turn up the engine, just make it burn cleaner? Itll be a little hotter because the fuel will be burning at a more complete rate. If need be, I will turn the pump down a little. Either way, a 354 diesel is going to have more power than the current 330 HD which has been pretty much ran out of oil because it busted several gaskets.

Compression specs for NA Perkins is 16:1
Comp specs for Turboed Perkins is 15.5:1

 

The addition of a turbo won't improve the fuel economy. It will hurt the fuel economy because of the increased back pressure at the exhaust port and subsequent increased pumping loss.

The only time the turbo will help fuel economy is if you are operating the engine on the bsfc "hook" where the engine is running out of air along the lug curve. Trust me on this, as I spent years and years doing diesel engine performance development for an engine oem.. The "add a turbo to improve fuel economy" myth was disproved many times early in my career. The turbo is there to increase power from a given package, and in later years to meet emission standards.

 

Hmm...didn't know that. Ive always heard people say turbo for fuel economy OR power. With your credentials, I must take your word for it. I understand the back pressure decreasing fuel economy. I mean, its not like putting bigger muffler is going to help if back pressure occurs at exhaust port. Now, I don't mean to argue with you and this is as a question, but wouldn't increased power from a constant amount of fuel=better economy? My only reason being that getting more power from the same amount of fuel because of a cleaner burn would result in less fuel needed to keep the truck going at a constant rate. We haul some corn if an overflow truck is need, but mostly seed for the planter and often going up fairly steep hills. Sure, the NA engine has plenty of power compared to the dinky gas it has in it, but I just figured I learn something from somebody who has experience in the diesel field, particularly in the performance section.

 

I thought the 354 was underpowered to use in a truck? I read that they only produce 100 hp non turbo and 120 with the turbo. The 330 has more hp than that but less torque right? What size truck are you putting it into? I have one available to me that was in an F250 and it ran fine. I wanted to put one in an N750 to replace the 391 but I feel it would be underpowered. The N750 is going to be a pickup and used as a toy hauler.

 

Back in the day, a turbo 6-354 Perkins could be rated at 160 hp, with a nice flat torque curve. Great for a pickup.

Dodge did use them as a option in there medium duty trucks in the 60's, but not great in hilly country. Way too much shifting with a manual on any hill, and hard to find something decent to put behind one like a Allison.

David

 

Yea, but a 2.0 L engine can have more horsepower than a 6.0 L. For something like a truck used for hauling 15 tons at its max, a 354 will be more than plenty. In fact, a 354 perkins has more torque than a 5.9 cummins when both turboed. Less HP, but more torque. Depending on the engine, some of the perkins could run 3200 RPM. Its been explained to me like this: Horsepower lets you go 200 miles an hour, torque lets you pull much much more at a lower speed. Usually, or at least in my experience, diesels run much higher on torque than they do HP. Ive only messed with ag diesel though so I can't say much as a general statement. I did find something interesting though. If someone takes a 20 foot long stick and mount it to your clutch, sit on it (say said individual weighs 200 lbs), then you could theoretically stall the engine even if it had 4000 ft-lbs of torque when you engage clutch. Its simple math really, but I just never thought about it that way. Forgive me if i am completely ignorant to a fact, I probably didn't realize it ;P