Rod thrown, what now?

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Schurkey

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Interesting info about the balancing of the engine. I had read that small blocks became internally balanced when they went to a 1-piece seal, figured that applied to big blocks. Def makes it harder to figure out what you need!
Small-blocks (except the now-extinct 400) used neutral-balance dampers and flywheels/flexplates UNTIL the 1-piece rear main seal crankshafts were introduced. At that point, the flexplate/flywheel gained an offset weight AND a smaller bolt-circle, although the damper stayed neutral-balanced.

Similarly, the 366, 396, 402, and 427 had neutral-balanced dampers and flywheels/flexplates, but the 454 always had offset weight at both ends--damper and flywheel/flexplate; although the two-piece rear main cranks--forged or cast--used the same amount of offset weight. That changed with the one-piece-seal cranks.

Note that an engine that has neutral-balanced damper and flywheel/flexplate can still be externally-balanced. The typical Chevy engine before the one-piece rear-main seals (except the 400 and 454) had neutral-balanced dampers and flywheels, but they carried offset weight behind the rear main bearing in the flange at the back of the crank. The flange had to be eliminated to fit the one-piece rear main seal, so that offset weight went onto the flywheel/flexplate instead.

Lots of folks--including people who should know better--claim that the older Chevy engines were internally balanced...but they weren't.
 
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stutaeng

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I'd swap a 350 and keep rocking that truck. Should be pretty easy to swap. Lot's of 350s still out there. Around here BBC are pretty rare nowadays.

You don't really hear much about the 305s anymore. Like they were lost in history or something. I don't think they powerhouses to begin with. At this point in time, I don't see why anyone swap or rebuild a 305 when you can drop in a 350 for same price and amount of work.
 

PlayingWithTBI

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The fuel pump is also a higher pressure pump so that will need swapped.
As @Schurkey mentioned, the 94 - 95 7.4L TBI ran smaller injectors at 28 - 32 PSI where, the earlier ones ran bigger injectors at 13 PSI. If it were me, I'd put in an ACDELCO EP381 pump from a 96 Vortec.

454s also came from the factory with a full float axle
Unless you can find one from a 454SS, they were SF 14 Bolt.
 

Dropped88

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As @Schurkey mentioned, the 94 - 95 7.4L TBI ran smaller injectors at 28 - 32 PSI where, the earlier ones ran bigger injectors at 13 PSI. If it were me, I'd put in an ACDELCO EP381 pump from a 96 Vortec.
I put a pump in my 92 from a 96 and that smooth up how the 454 runs and it'll hold the cone spray pattern when you rev it while watching
 

Eargesplitten

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I'm not sure how to tell which transmission I have, I know I have a 10 bolt axle. I thought 5lm60 but I'm not sure where the markings on the transmission are or which RPO code I'm looking for. I'd rather check the transmission itself anyway since I know this thing had the transmission done ~3k miles ago and I'm not sure if that consisted of a rebuild or dropping a reman in.

The truck is heading to the shop to make sure it didn't take the transmission or anything with it since the car hauler I rented from u-haul is a couple feet too short to fit the truck, so I'll figure out what to do from there. My initial searching around here found that the only TBI 350s on facebook/craigslist have bad rings or head gaskets or something else. When I referenced it not being a long haul heavy duty vehicle I was primarily referring to how I'm pretty sure it would still max out at 6-8k towing capacity even with the bigger motor, I don't remember exactly. And I've got a limited amount of space for a radiator and a limited amount of fan cooling so I'm not going to be roaring over mountain passes with a mansion on wheels in tow. The engine is a '94 so looks like that means the smaller injectors at higher pressure. I've heard mixed things about the Harris Tuning guy but his page says that the fuel pump needs to be replaced if you're going over 230HP. This would be right on the line depending on airflow so I might need to do that. AC concerns would be nice to address but the R12 AC on this thing is broken anyway, I had a shop fill it up and it stopped working within a week.

What's difficult about doing engine mounts on a 4x4? All my other vehicles are smaller Japanese vehicles so when I look at this thing I see a heavier but much more spacious vehicle to work on. Half the time I'm working on this thing I don't even need to put it up on jackstands. I also have a decent selection of power tools because we're all doomed to become our fathers. And an engine hoist, that should go without saying.

The engine is this one here: https://denver.craigslist.org/pts/d/denver-tbi-454-motor/7520657933.html it looks like it has the flywheel and I thought it had all the assorted accessory gubbins but maybe not now that I look at it, when I made this thread I was 24 hours into being awake 30 hours trying to get this thing sorted and off the side of I-70. Flywheel looks a bit rusty so I'd probably want to put a new one on there anyway. Does the exhaust from a small block bolt up to the manifolds of a big block? I'm guessing no but hoping I'm wrong. There's a welder in town that I'm on good terms with so I could probably take him the cats and mufflers and pay him to fab something up once the motor is in. Or I could take this chance to learn how to MIG weld if I feel up for it at that point. The current exhaust is rusted to hell and someone stole the muffler thinking it was the cat so I need to do the exhaust eventually anyway. Just would be nice for that to not be immediately necessary since despite how redneck this town is I'm pretty sure I'd get pulled over fast driving with open headers even to get it to the shop.

Edit: Random thought, putting a non-TBI 350 (with the non-vortec head pattern) in and putting my tbi intake on top of it would be a terrible idea, right? Since it wouldn't know how much fuel to provide for the airflow and compression ratios? I'm used to port fuel injection where that's not even an option.
 
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packer0440

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I'm not sure how to tell which transmission I have, I know I have a 10 bolt axle. I thought 5lm60 but I'm not sure where the markings on the transmission are or which RPO code I'm looking for. I'd rather check the transmission itself anyway since I know this thing had the transmission done ~3k miles ago and I'm not sure if that consisted of a rebuild or dropping a reman in.

The truck is heading to the shop to make sure it didn't take the transmission or anything with it since the car hauler I rented from u-haul is a couple feet too short to fit the truck, so I'll figure out what to do from there. My initial searching around here found that the only TBI 350s on facebook/craigslist have bad rings or head gaskets or something else. When I referenced it not being a long haul heavy duty vehicle I was primarily referring to how I'm pretty sure it would still max out at 6-8k towing capacity even with the bigger motor, I don't remember exactly. And I've got a limited amount of space for a radiator and a limited amount of fan cooling so I'm not going to be roaring over mountain passes with a mansion on wheels in tow. The engine is a '94 so looks like that means the smaller injectors at higher pressure. I've heard mixed things about the Harris Tuning guy but his page says that the fuel pump needs to be replaced if you're going over 230HP. This would be right on the line depending on airflow so I might need to do that. AC concerns would be nice to address but the R12 AC on this thing is broken anyway, I had a shop fill it up and it stopped working within a week.

What's difficult about doing engine mounts on a 4x4? All my other vehicles are smaller Japanese vehicles so when I look at this thing I see a heavier but much more spacious vehicle to work on. Half the time I'm working on this thing I don't even need to put it up on jackstands. I also have a decent selection of power tools because we're all doomed to become our fathers. And an engine hoist, that should go without saying.

The engine is this one here: https://denver.craigslist.org/pts/d/denver-tbi-454-motor/7520657933.html it looks like it has the flywheel and I thought it had all the assorted accessory gubbins but maybe not now that I look at it, when I made this thread I was 24 hours into being awake 30 hours trying to get this thing sorted and off the side of I-70. Flywheel looks a bit rusty so I'd probably want to put a new one on there anyway. Does the exhaust from a small block bolt up to the manifolds of a big block? I'm guessing no but hoping I'm wrong. There's a welder in town that I'm on good terms with so I could probably take him the cats and mufflers and pay him to fab something up once the motor is in. Or I could take this chance to learn how to MIG weld if I feel up for it at that point. The current exhaust is rusted to hell and someone stole the muffler thinking it was the cat so I need to do the exhaust eventually anyway. Just would be nice for that to not be immediately necessary since despite how redneck this town is I'm pretty sure I'd get pulled over fast driving with open headers even to get it to the shop.
I think the 350 crossover pipe is the same as the 454. After that the layout might differ but you should be able to reuse that at least. Based on pics it looks like the bracket for the AC and tensioner and possibly the idler isn’t there. I would make sure you would be able to get those before making any decisions. Flywheel looks like it could be turned and be ok. I would also check if it’s off of a 4x4.
 

Eargesplitten

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Good catch, thanks. Why does it being from a 4x4 or not make a difference? Did they have different manifold designs to avoid hitting the crossmember or something?
 

packer0440

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Good catch, thanks. Why does it being from a 4x4 or not make a difference? Did they have different manifold designs to avoid hitting the crossmember or something?
Different oil filter adapter so there is clearance for it. These might still be available but not sure. Might have a slightly different shape for the oil pan but I can’t confirm this.
 
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