Hey everyone, I’m seeking some advice for what to do next. The situation is that I’ve pulled the engine out of the truck due to some nasty clicking noises and nearly no oil pressure at idle. The engine is a 400 and has seen some abuse before I got it.

Upon inspection the cam sprocket lost all its nylon teeth and somehow didn’t jump timing. Also I’m unsure if one of the cylinders is cracked. There’s some spiderweb like patterns along #7 that looks like corrosion more than anything but I can catch a nail on it going in one direction. Haven’t got it magna-fluxed quite yet since there are no reputable machine shops within an hour of me. Does it sound like a crack or maybe just a ridge for having sat for 12 years?

The original idea was new bearings, gaskets, cam, intake. Just freshen it up and get a little more juice, but now I’m at a standstill and don’t know what the best option would be.

I understand my options are the 400/351m, 429, and 460 but after looking at remanufactured engine pricing and rebuilding a used engine, it’s not quite as cheap as I would have assumed which leads me down the idea of coyote swapping from a wrecked 5.0 (ambitious I know). After machine work and parts it may be close to the $4500 I can get the whole car for. I also know someone with plenty of experience who has offered to help with such a crazy project just for the sake of it being ridiculous.

I’d like to say I’m still a little green when it comes to this stuff, most of knowledge comes from Roadkill, and Vice grip garage.

What do you guys think is the best option, or am I being delusional?

As always I really appreciate any input you have to offer.

Here are the questionable marks on the cylinder wall.

 

The hone marks are perfectly normal. I can't tell what the mark is but it looks like light rust that's scuffed away. not sure, but if you can't feel it forget it. it's not a crack.

The 429-460 are a much better engine than the 335 series you have. and you can do a conversion if you want to spend the extra money. but if all you're after is an engine to drive your pickup I'd fix whatever your engine needs and drive. worst case you have to bore it and rebuild it, but unless it's worse than your pictures look that may not be necessary.

 

Where did you come up with your estimate of $4500 for a coyote swap? Would you be using an adapter to use your existing transmission, or would you be using the type of transmission that would normally come with a coyote?
Would you be keeping all the electronics and needing a harness and computer? Or would you be converting it to carburetor somehow?
I’m just asking, because I can’t imagine a new engine swap is any cheaper than rebuilding your existing one.
Yes, prices have certainly gone up. And I’m sure rebuilding an engine these days with the full complement of new parts, could easily touch 4 to $5000. But modern swaps can have some expenses of their own!

 

2 wheel or 4 wheel drive? Much easier to engine swap a 2 wheel.

How are you going to drive the truck? Daily driver, weekend toy?

I'd throw bearings, timing chain, & gaskets in it & run it for a while, if it is a weekend toy.

 

Bing Videos He gets into cost 3/4 way through.

 

If you just want a capable reliable driver, I'd say rings, bearings, gaskets, and timing chain set, head refresh, and keep it. I see cross hatch pattern and scuffs and looks like maybe a light bit of rust from maybe where the truck sat a long time unused and that one piston was at top center, so light rust never got obliterated by a start up. If not sure about a crack, have the block hot tanked and tested at a local machine shop, like the one that you get to do the heads?

What is a coyote or BB swap gonna do for you .... ie:, what is planned usage? If you go with the BB 429/460, you'd still be wanting to refresh it? Then there's cost with the swaps too.

 

For those asking the truck is a 2Wd and the estimate for the coyote swap was based off of just the donor car with drivetrain in tact. The car would be totally stripped engine, trans, ecu, wiring, basically everything I feasibly could. Definetly a lot of nickel and dime stuff that would add up quick,$4500 was just the cost of the car.

The end goal is a reliable engine with roughly 300+ hp. Anything beyond that and it’s just for the fun factor. Fun but functional when I need it to pull junk.

The plan is keep the 400 if possible, rebuild it, and throw the Edelbrock performance kit from JEGS on it. That should be enough to have some fun with every now and again.

if it needs bored I’ll go with the Tmeyer zero deck pistons cause why not. At 9.3:1 would 87 still be usable or would I most likely need higher octane? Not a huge deal just a consideration.

also last question, there’s a bit of a ridge on all the cylinders, if it doesn’t need bored I assume it’s just cheap insurance to ream it out?

thank you all so much for all the help and input

 

9.3:1 you'd want at least pump super.

You'll need to have a machinist measure the bore if you don't have the equipment to do it right. if it doesn't need bored you'll want to use a ridge reamer to take whatever is on top off before you pull the pistons. if it's a slight ridge you might get away without it. hone the cylinders and put a set of cast rings in. your bottom end probably needs work on a 400 and have the heads checked out good.

If you're sticking with stock pistons it's pretty much a waste to spend money on anything performance related. you just don't have the compression to make anything happen.

 

Hopefully a goofy question but one of the rods has studs that seem to be just a little bit flared out. I’ve gotta squeeze them slightly inward to get the cap on. Is this normal or should I be concerned?

 

You should always have the rods reconditioned.

It's not unusual for the caps to drag the bolts. but if it takes more than fingers to get the cap on the bolts I'd have it checked.