NissanDiesel Forums

Thought I would share this with you folks!

Just found this forum a couple weeks ago and I have been doing lots of reading. My Dad bought this truck when I was younger, we probably put over 200,000 miles on it before it was parked about 20 years ago. The master cylinder for the brakes was sticking, and nobody ever fixed it. From what I have been reading, it is a marine model. I don't know if it came with the turbo, or if it was added. The injector pump doesn't look to have the boost comp. on it, but it was working fine for years.

Thanks for posting these pics, it's always interesting to see to what uses the Nissan diesels have been put.

I agree that this looks like a turbo manifold setup glued to a non-turbo IP, or alternatively a non-turbo IP may have been transplanted to a turbo-application engine.

The (excellent) picture of the valve cover spec label is the clue: 3200 RPM HP rating is low for automotive trim, and the CN6-33 is the Chrysler model number for the marine application version.

The automotive-trim turbo version of this engine is rated closer to 102 HP, but that's with the IP that mates to it. You are safer running it as it is now, as the turbo version has several upgrades that are pretty essential for long-term reliability under boost.

Do you have "plans" for this setup?

""Do you have "plans" for this setup?""

I'm not sure what you mean? The engine was retrofitted by a friend many years ago, I think they just designed as they built it.

I was interested in doing another conversion with this engine, but it never had very much power. Looking at the service manual, it is also indirect injection, and I dont' think I will be able to get much more power out of it. I will probably go with the Cummins 4bt.......in my opinion it is a better engine for performance, and buying aftermarket parts.

dmh13433 wrote:I was interested in doing another conversion with this engine, but it never had very much power.

I'm not surprised -- figure the HP rating, then add maybe 10% for the turbo but without boost compensation, then harness it to about 80% more weight than it would have moved in automotive trim -- I'm not at all surprised that the performance was not all that great

You're right—your SD33 is the marine version (CN6‑33) rated at just 3,200 RPM, not the automotive turbo model, which explains the lack of power. As mentioned on the forum, it looks like you’ve got a turbo manifold on a non‑turbo injection pump—so it runs, but not efficiently.

I’ve experienced a similar setup before, and I know how underwhelming it can feel in a heavier vehicle. For detailed specs and comparisons, I often refer to autouserguide .com a handy resource for checking compatibility and performance data.

For real performance, upgrading to a Cummins 4BT is a smart move. It fits well, has strong aftermarket support, and delivers much better torque and reliability. Your current setup works, but if you want serious power, the 4BT is the way to go.

You're right—your SD33 is the marine version (CN6‑33) rated at just 3,200 RPM, not the automotive turbo model, which explains the lack of power. As mentioned on the forum, it looks like you’ve got a turbo manifold on a non‑turbo injection pump—so it runs, but not efficiently.

I’ve experienced a similar setup before, and I know how underwhelming it can feel in a heavier vehicle. For detailed specs and comparisons, I often refer to autouserguide .com a handy resource for checking compatibility and performance data.

For real performance, upgrading to a Cummins 4BT is a smart move. It fits well, has strong aftermarket support, and delivers much better torque and reliability. Your current setup works, but if you want serious power, the 4BT is the way to go.