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[94_Ranger]

What is the difference between 5.2 and 5.7 connecting rods? Will using 2.5 internals in my 2.3 raise the compression alot? I was thinking about using the 2.5 internals in a 2.3 turbo, will it work?

 

[Wicked_Sludge]

i dont know about 2.5 parts in a 2.3...but i do know raising the compression on a boosted motor is a bad idea. you'll have a very hard time controlling detonation. if anything, you want to lower your static compression.

 

[shadetree]

What is the difference between 5.2 and 5.7 connecting rods? Will using 2.5 internals in my 2.3 raise the compression alot? I was thinking about using the 2.5 internals in a 2.3 turbo, will it work?

The difference in the 2.3 and the 2.5 is the crankshaft, the 2.5 has a longer stroke. In order to keep the piston from protruding into the combustion chamber on the 2.3, you have to shorten the rod or move the pin location in the piston or both. The compression will change very little. The 2.3 and 2.5 blocks are the same except for the turbo block. shady

 

[TireIron]

also using the 2.5 rods on a boosted application is not a good idea as they are cheaper quality sintered metal than the original 2.3 rods. If you want to stroke your boosted block you will want forged pistons anyway so you would need the 2.5 crank, forged 2.5 pistons and some aftermarket quality 2.5 rods.

 

[shadetree]

also using the 2.5 rods on a boosted application is not a good idea as they are cheaper quality sintered metal than the original 2.3 rods. If you want to stroke your boosted block you will want forged pistons anyway so you would need the 2.5 crank, forged 2.5 pistons and some aftermarket quality 2.5 rods.

You might want to re-think your thinking.

"Stronger than "pink"
The sintered powder metal connecting rod is a mainstay of almost every auto manufacturer, as this construction method produces very strong and comparatively lightweight parts. The Howards rods also use a "fractured" cap. This means the rod and cap are formed as a single piece and the cap is carefully "split" afterward. The idea is to create a puzzle-piece fit that is ultimately stronger and better sealing than machined/saw-cut rods and caps. Howards specifies premium ARP hardware, including ARP 2000 cap screws. But before you wave off the thought of mere regular-production engines not being up to the performance standards you would expect, the truth is, that compared to old-school rods of the muscle car days, powder metal parts are much stronger. In fact, the powder metal rods in the garden variety 3800 V-6 of your wife's Impala are stronger than the old Chevy "pink" rods. And as for the rods in the new Corvette's LS2 or LS7 engine, well, those much-respected forged steel pink rods are downright brittle in comparison. Howards says their new rods rate a 42 on the HRC hardness scale, with the typical "pink" rod delivering around a rating of 20." shady

 

[TireIron]

actually I'm comparing the proven strength of the original 2.3 rods to the 2.5 rods. The 2.5 rods have been known to be significantly weaker than the 2.3 rods of all the previous motors. I'm not saying anything bad about factory parts, hell the rods in the 2.3 motor up until the 2.5 was released were the same rods used in the original turbo blocks.

 

[pillen140]

its funny when two people that know their crap have different opinions

 

[shadetree]

Powdered metal is the current technlogy. It is used by most all mfgr. The rods are used in diesels as well as gasoline, in high horsepower apps., as well as lower hp. Ford pioneered the process. This would be a tribute to their strength.

I have not encountered, or heard of, a massive failure in the 2.5 due to rod problems.

However, like all modifications to engines, one has to take into account the structure of the lower end and plan accordingly. The stock rods in the early turbo engines are good for over 200 hp, but if you intend to go higher, even these rods need to be changed to a stronger piece. shady