2.5 Engine rebuild

[Nmcgorry]

I am currently in the middle of my first TJ rebuild 2.5 l4 and I had the cylinders bored to 0.060 over and I already replaced the piston heads, cam shaft, water pump, timing chain, cam sprocket, oil pump, just about every gasket in the engine. So I was wondering is there anything else that needs to be upgraded or replaced when rebuilding a TJ engine with overboard pistons?

 

[SSTJ]

Watching, just to learn. I have no advice to offer.

About how much power do you expect you'll gain from the enlarging the cylinders? And do you expect you'll need a custom tune to accommodate the changes?

 

[SSTJ]

About how much power do you expect you'll gain from the enlarging the cylinders? And do you expect you'll need a custom tune to accommodate the changes?

Just for fun, here's what Chat GPT thinks the answer is:

"After the cylinders were bored out by 0.060 inches, the engine's displacement increased from approximately 2,464 cc (2.464 liters) to 2,541 cc (2.541 liters), resulting in an increase of about 77 cc or 0.077 liters in displacement.

The actual power increase from this change can vary widely depending on factors such as the engine's overall condition, the efficiency of the air/fuel mixture, the tuning, and other modifications made to the engine. However, as a rough estimate, for naturally aspirated engines, an increase of 10-20 horsepower for every 0.1-liter increase in displacement could be expected under optimal conditions. This assumes that the engine and all its components are in good condition and that the engine management system is appropriately tuned to take advantage of the increased displacement.

Given the increase of approximately 0.077 liters in our case, this might translate to an increase of roughly 7.7 to 15.4 horsepower, under optimal conditions and assuming that other modifications (like the camshaft, exhaust system, etc.) synergize well with the increased displacement.

It's important to note that these figures are very approximate. The actual gain could be higher or lower based on the specific details of the rebuild, including how well the engine components work together and any additional modifications that have been made. Tuning and optimizing the engine to run with the increased displacement is crucial to realizing the potential power gains."

 

[Nmcgorry]

Just for fun, here's what Chat GPT thinks the answer is:

"After the cylinders were bored out by 0.060 inches, the engine's displacement increased from approximately 2,464 cc (2.464 liters) to 2,541 cc (2.541 liters), resulting in an increase of about 77 cc or 0.077 liters in displacement.

The actual power increase from this change can vary widely depending on factors such as the engine's overall condition, the efficiency of the air/fuel mixture, the tuning, and other modifications made to the engine. However, as a rough estimate, for naturally aspirated engines, an increase of 10-20 horsepower for every 0.1-liter increase in displacement could be expected under optimal conditions. This assumes that the engine and all its components are in good condition and that the engine management system is appropriately tuned to take advantage of the increased displacement.

Given the increase of approximately 0.077 liters in our case, this might translate to an increase of roughly 7.7 to 15.4 horsepower, under optimal conditions and assuming that other modifications (like the camshaft, exhaust system, etc.) synergize well with the increased displacement.

It's important to note that these figures are very approximate. The actual gain could be higher or lower based on the specific details of the rebuild, including how well the engine components work together and any additional modifications that have been made. Tuning and optimizing the engine to run with the increased displacement is crucial to realizing the potential power gains."

Yeah scouring the depths of a bunch of other random forums seems like the old exhaust might have to go

 

[Nmcgorry]

Watching, just to learn. I have no advice to offer.

About how much power do you expect you'll gain from the enlarging the cylinders? And do you expect you'll need a custom tune to accommodate the changes?

Watching, just to learn. I have no advice to offer.

About how much power do you expect you'll gain from the enlarging the cylinders? And do you expect you'll need a custom tune to accommodate the changes?

Not much about the 10 to 20 range. I don’t really think to it’ll need a tune not really going for performance really just trying to get it back on the road.