Building a big cam 3 400

I don't know what your level of engine building is so I can't advise you whether to rebuild or not yourself.

The lpf liners means they are lower press-fit. In the earlier big cam engines, I think before big cam 4, the engines from the factory had upper press-fit liners. They worked, but they moved around quite a bit. So then the engineers realized they can install lower press-fit liners and they're much stronger.

If your engine has upper press-fit liners then someone has to come out with the tool and they cut the block to fit the lower press-fit liners. If you are doing a rebuild and especially with more horsepower you want to have lower press-fit liners.

As far as the crankshaft goes as long as the clearances are good it's just rebuilt. If the crank has to come out then the machine shop will magnaflux and cut it.

Now on the front of the engine there is a balancer and if the engine has some time on it you should just replace it.

The camshaft is the same as the crankshaft. If there's nothing wrong you just keep using it. I would only replace that if you are certain there is significant wear that it needs to be replaced.

But what I would replace are all of the accessory and maintenance items and make certain that you have the timing tool and the timing of that engine is set correctly.

 

Lpf is .370 deep at the counter bore. 20/40 is an over size liner. Check block for cracks around counterbore and to water jacket holes. If is cracked you need water hole inserts also

 

Cummins liners had the part number stamped in them. You can tell what they are and replace as is that way.
Many aftermarket liners had numbers painted on them. You may never find a number and have to measure everything.
As said: Only go back with lower press fit liners.

 

Hello guys, I have a Big cam 1 CPL 327. She’s working fine for now but I need more boost/ power. Can I turn her into any CPL ?? Thanks in advance?

 

Yes but you need to match the right parts.

You need to make certain that you have the correct camshaft and pistons and liners and that your timing is set correctly. Depending on your engine you may need the offset key for the timing gear.

For whatever CPL then you have to have someone go over the pump and have the pump set for that fuel code and have the correct injectors.

Some will tell you you have to have the turbo for that CPL. I have been told there's a large and small housing and if you have the larger housing that's good to 600 horsepower. There also are other turbos to upgrade to. I do believe the 350 and 400 turbos are very similar.

@OLDSKOOLERnWV changed his CPL.

He has good information.

 

Yes, you can redo it in another CPL. All depends on how far you want to go.

I don’t remember what CPL 327 is so I’d have to look in my book.

My engine was originally a CPL 0749 @ 315 horsepower.
I converted it completely to a CPL 625 @ 400 horsepower, along with other minor modifications.

Sometimes the best thing is the simple thing, a nice set of injectors along with a matched pump may be the ticket for you?

I just got my new firing pins from Premco yesterday. Little larger than stock and all flowed and matched evenly.
I’ve used injectors from other shops, but Premco seems to have the edge on the others, at least from my experience.

 

Did you upgrade the turbo ? On my BC 1 had the injectors and pump flow to match from a reliable Cummins shop back in the day. I installed the pulse manifold and the Holset HT 4 turbo. I still have the truck, parked though ….

 

I’m running a Holsett HT60, same as used on the 525 N14….

 

The tuner I knew at the time(RIP) was pretty sharp. He wanted send out the pistons to get ceramic coated when the time came to do an inframe. The HT4 I guess for my era at the time was the HT 4. But a lot has changed since back then. According to the fuel pump shop, the rail pressure was supposed to be over 300. It ran great and had Calibrate to it wouldn’t smoke alot when I mashed on it. It was within they had started using the sniffers for smoke opacity test. We are talking about over 25 years ago. If the ceramic coated pistons would of been done, I’m sure he would of told the shop to and him a fuel pump and different injectors to get more HP. Also he talk about backing off the top stop of the injectors when he adjusted them. He said I was more precise.