5.3 Rebuild Cost

[centerville]

So I have been looking around and $2500 seems to be the number. It's not bad just making sure I am in the ball park. I am not a mechanic so some of this will have to be subbed out.

The gen 3 I am looking at still has the 305tpi so it will need the 5.3 to be competitive. Just trying to get a ballpark number on this. Thanks.

[mach1]

So I have been looking around and $2500 seems to be the number. It's not bad just making sure I am in the ball park. I am not a mechanic so some of this will have to be subbed out.

The gen 3 I am looking at still has the 305tpi so it will need the 5.3 to be competitive. Just trying to get a ballpark number on this. Thanks.

How hard is it to get the 305 to required power levels?

[RichardP]

How hard is it to get the 305 to required power levels?

Easy. Within CMC rules... good luck.


Richard P.

[RichardP]

So I have been looking around and $2500 seems to be the number. It's not bad just making sure I am in the ball park. I am not a mechanic so some of this will have to be subbed out.

The gen 3 I am looking at still has the 305tpi so it will need the 5.3 to be competitive. Just trying to get a ballpark number on this. Thanks.

A well used stock 5.3 still makes plenty of power. No real need to rebuild it. A 100K mile stock motor that has never been opened up is less likely to blow up than a fresh rebuild...


Richard P.

[Suck fumes]

assuming the person who used to own that 100k mile motor was actually maintaining it properly during its life and nothing got jolted inside when that said street car was wrecked.

If you have a GOOD engine builder that actually knows what he’s doing then your motor will last a long time as long as you treat it nicely. I had my motor built in 2013 and it makes pretty close to the same numbers now after 4yrs of thrashing on it.

[centerville]

How hard is it to get the 305 to required power levels?
No clue yet. I can only digest so much info a day and still do my job.

A well used stock 5.3 still makes plenty of power. No real need to rebuild it. A 100K mile stock motor that has never been opened up is less likely to blow up than a fresh rebuild...

I will somewhat agree with this statement. But without knowing how it was maintained its all just a gamble. In all my searching last night lowest mileage was 111k then jumped to 135k, both of those a rebuild numbers to me.

Richard P.


assuming the person who used to own that 100k mile motor was actually maintaining it properly during its life and nothing got jolted inside when that said street car was wrecked.

If you have a GOOD engine builder that actually knows what he’s doing then your motor will last a long time as long as you treat it nicely. I had my motor built in 2013 and it makes pretty close to the same numbers now after 4yrs of thrashing on it.
^this^

[michaelmosty]

How hard is it to get the 305 to required power levels?

A 305 with a carb gets there nicely. IIRC, Bob Denton's 3rd gen Firebird from the Great Lakes region was around 260hp/305tq.
I'm not a carb guy but I'd at least look into that before shelling out the money for a 5.3, new trans, wiring, etc. Would at least be worth the comparison.

[Fbody383]

I'll get Sean to jump in if he doesn't see this. If you put it in a third gen the truck accessory setup is the cheap way to go, but needs additional rules review. For some crazy reasons.

[Pranav]

If you can find a lower mileage 5.3 with a known history, simply throwing on beehive springs and hardened/machined valve locks/retainers and a baffled camaro oil pan should be enough.

I bought a 120k mile long block and had it gone through with $3k in parts/labor by a good engine builder. I simply rehoned and skipped the main align bore, good coated bearings, re used pistons, roadrace lifters and coated bearings.

I have not been kind to this motor all year and yet I have perfectly clean oil filters after every 3 day race weekend.

If you get a steel block 5.3, realize that you may or may have rusty coolant passages if it has sat in a yard. You will also have to drill a hole in one of the front mounting bosses for the alternator bracket. The aluminum block requires a dipstick home to be drilled (because front sump pan mounted dipstick in truck apps). It is also lighter and runs cooler if you are ok running at 3300lbs.

If you can swing the cost/effort to get a 5.3, it is well worth it.

It's just a tough, durable package that is well within it's stride when taking it up to "only" 6k, especially if you spend the money on good valve springs. Neutral balance crank, 6 bolts mains, and an ignition system that's solid as hell.

The only real issue with the 5.3/ls is managing crankcase pressure and oil sucking into the intake due to the deep skirt block and super shallow valve covers with tiny breather hoses, but I've pretty much fixed that with huge breather hoses .

[Pranav]

...and yeah there is an official requirement that you run Camaro accessories, but it fits just fine and actually better with truck accessories in a 3rd gen.

Doing a 5.3 swap into a 3rd gen is much cheaper than it is into an lt1 4th gen, ask me how I know.

[Pranav]

Also ask Sean nicely and he may have a lead on a super low mileage aluminum 5.3. Nicely.

[centerville]

If you can find a lower mileage 5.3 with a known history, simply throwing on beehive springs and hardened/machined valve locks/retainers and a baffled camaro oil pan should be enough.

I bought a 120k mile long block and had it gone through with $3k in parts/labor by a good engine builder. I simply rehoned and skipped the main align bore, good coated bearings, re used pistons, roadrace lifters and coated bearings.

I have not been kind to this motor all year and yet I have perfectly clean oil filters after every 3 day race weekend.

If you get a steel block 5.3, realize that you may or may have rusty coolant passages if it has sat in a yard. You will also have to drill a hole in one of the front mounting bosses for the alternator bracket. The aluminum block requires a dipstick home to be drilled (because front sump pan mounted dipstick in truck apps). It is also lighter and runs cooler if you are ok running at 3300lbs.

If you can swing the cost/effort to get a 5.3, it is well worth it.

It's just a tough, durable package that is well within it's stride when taking it up to "only" 6k, especially if you spend the money on good valve springs. Neutral balance crank, 6 bolts mains, and an ignition system that's solid as hell.

The only real issue with the 5.3/ls is managing crankcase pressure and oil sucking into the intake due to the deep skirt block and super shallow valve covers with tiny breather hoses, but I've pretty much fixed that with huge breather hoses .

Thanks for all the detailed info.

Hopefully tomorrow or Thursday I can get the deal done on the car. Then make car trackable again. Then we will see how patient I can be.

Thanks everyone!

[Supercharged111]

I'd just rering it in my garage if it really needed rebuilt. Crank polish, new rings/bearings and done. I have a pull and pay aluminum 5.3 on the stand with 170k and my plan A is just run it.