I have searched but cannot find a reference to what the actual issue is with DE rods.
Several posts here have the members simply replacing the bolts with good ARP items,but I would like some input on what is actually wrong with the rods and is a bolt replace ( read easy to do ) of any real use.
Aftermarket rods are cheap enough, as is a pump replacement, but making the engine reliable to use at say 7500 does then require a full strip down, and my DE has only 20K on the clock.

 

I cant believe that 103 people from this forum have looked at my simple question about why everywhere I look im told DE rods are crap, but there are no answers about what is the actual issue.
Replacing the rod bolts is easy,and several people have done just that - but is that just a fix dreamed up by someone with no proof it actually helps to stop rods exiting the block when revving the thing to 7500.

 

The rods are weak when dealing with FI. If you're staying N/A then the rods aren't just going to miraculously fail. Worry about the bearings, valvetrain and oil pump.

 

+1 the rods aren't crap but the instant blast of TQ from turbos specifically is what kills them. Up to around 400whp they're fine. If you expect a DE to perform reliably at 7500rpm and make power you've got a lot of work to do...

 

Now I have some info - thanks alot.
So once I have finished all the prep work for the planned mods to this engine, what you are saying is that the weak points need to be addressed.
Change the valve springs to protect the valve gear & change the pump to maintain oil pressure.
But is there hard evidence that the rods will survive 7500 if I change to ARP bolts.
I ask this as all these mods are easy to do in my own workshop without pulling the block out.
The mods include a trick design 3 step long tube headers with merge collectors and full twin catback system.
Then a Kinetix V+ with 75mm TB off a 2010 Maxima and a 75mm Flow Meter tube fed by a modded Popcharger.
The Kinetix has very thick composite walls so was easy to port out to 75mm using just flap wheels,and as an aside I can see part of the reason these dont work well using stock components, the short turn radius into the plenum is a shocking piece of flow design ( or lack of it I should say ) - but again, was easy to correct.
Lastly it will be tuned via an Osiris cable.

 

I think the rods would be fine with ARP bolts, I'd also do the headgasket and ARP head studs. Cams, valve springs, upgraded oil pump, ideally port the heads but that gets expensive. Sounds fun. Are you going to tune it yourself?

 

When using long tube headers, upgraded exhaust cams make a world of difference. Don't be surprised if you gain 30whp/30wtq from 4k-redline after adding cams and a tune

 

What are you trying to accomplish? Factory rods are completely fine and do not need to be replaced. The only reason you would want to look at having them replaced is if you are running 400+whp. If you are running an N/A motor and not reving past 7200rpm there is no need.

 

My question is why the need to rev to or past 7500 rpm.

 

Because racecar

 

Oh okay give some feedback on your findings.

 

I dont subscribe to the idea that HP is a main factor in the longevity of parts like rods.
Simply put the main (inertial) loads on the crank/rods/pistons are a function of the rpm alone.
You can double the power output of an engine and the gas loads are still an order of magnitude less than the piston having to effectively be stopped at TDC and BDC.
Thus its rpm that kills these parts, along with the valve train if the springs cant cope.
I fully accept that the head bolts may not be sufficiently strong and this would lead to gasket failure as well.
Nissan themselves pointed the way to making power with this engine when they made the corporate ( read very conservative ) decision to raise the rev limit in the next revision of the mechanical pieces,beefing up the rods, bolts,springs etc.
Reving this powerplant to 7500 is still well within the capabilities of many hi performance engines these days,with similar bore/stroke dimensions and I just dont want to go there if the rods are actually fundamentally flawed in design from the get go.