Weak point in the E and DE engines????

[Apollo8642]

Me and a friend are having are engines rebuilt, mapped and blue print.I have the KA24DE and my friend has the KA24E engines and are engine guy mostly specializes in Volks engines but is branching out to Nissan engines (he doesn't like Honda or Acura engines by the way).

Are guy wants to know about any weak parts of the KA engines, may it be any place in the block or in the head you name it, ect????

Any web sites or anything would be helpful.

:help :help :help

[SingleCamSam]

Piston ring lands. Pathetically small.

[Altiman94]

The # 3 cylinder seems to always be the cause of the DE's downfall. Leans out and goes boooooom

[SingleCamSam]

Think that could be a problem with the intake mani? One cylinder gets too much air.

[red240ne]

rods are pretty good, but with boost they don't seem to last very long. blown KA's always seem to be the fault of the connecting rods.

[cnichols]

The # 3 cylinder seems to always be the cause of the DE's downfall. Leans out and goes boooooom

He's right....definitely something to look into.

[cnichols]

rods are pretty good, but with boost they don't seem to last very long. blown KA's always seem to be the fault of the connecting rods.

Probably because our rods are ridiculously long.

[Aries]

I'd have to say the imbalance of air delivery in the stock intake manifold to the runners, and the timing chain are the weakest links.

[_dk]

Quote »Probably because our rods are ridiculously long.[/quote]???

if that's bad, why does nissan motorsports make a longer set?

[cnichols]

because they can...hell...I don't know...but you have to admit that our rods are very long. May not be the reason the engine fails....but they are definitely longer than normal.

[nlzmo400r]

well the longer the rods obviously the more risk you'll have at higher revs and of cousre turbo pressure, and the reason they make longer ones is for more torque and such, my QR has like 1oomm bore and stroke, and i know the rods will fling out of the block of if i turbo it, they are ridiculously long

[C-Kwik]

If anyone breaks a rod, then the tuning was pathetically horrible or a problem that caused the fuel to lean out, ignition to advance or the boost to spike to rediculous levels. You'ld likely see piston ring lands, break before rods give.

As far as rod length, I'd say that's not a weak point. Weak rods are a result of not enough metal, or material that is not strong enough. Longer rods are used because they keep rod angles between the top of the rod and the bottom of the rod more vertical. Short rods have to push on the crank at more of a horizontal angle as the crank reaches the 90 degrees from TDC. Longer rods allow most of the force to be in more of an downward motion. Keeping in mind a piston is designed to place a downward load, this would provide the best efficiency in converting linear energy into rotational energy.

I'd agree more with the single cylinder issue. Most motors actually have a similar issue though, but sometimes for different reasons. But if I were to point out a weakness of the KA, it would be the relatively low mechanical redline.

[Apollo8642]

Keep it coming, and does any one know of any web sites that talk about the fine tuning of a KA engine or any other place for that matter?And are there any problems in the heads (E and DE), or the trani?

Sweet info peoples, thanks.

[SingleCamSam]

No problems in the heads or transmission. Nissan makes pretty solid stuff.

[McAdam]

the ridiculiously long stroke is a problem and a reason why they dont like to rev. half counterweights instead of full counterweights. on the E motors, the timing chain guides really suck. they fall apart because the plastic is brittle and then the peices clog up the oil pick up screen and your motor throws a rod! I dont know much about the DE motors.

McAdam

[Aries]

Keep it coming, and does any one know of any web sites that talk about the fine tuning of a KA engine or any other place for that matter?And are there any problems in the heads (E and DE), or the trani?

Sweet info peoples, thanks.

start a new thread on tuning, and you'll get what you want I'll even throw in my expertise:)

[C-Kwik]

the ridiculiously long stroke is a problem and a reason why they dont like to rev. half counterweights instead of full counterweights. on the E motors, the timing chain guides really suck. they fall apart because the plastic is brittle and then the peices clog up the oil pick up screen and your motor throws a rod! I dont know much about the DE motors.

McAdam

To make sure everyone is clear, long rods and long strokes are two different things.

As far as chain guides, the original ones are crap since they are mede entirely of plastic. The replacments are backed with metal and I haven't heard of any problems with these...

[McAdam]

yeah, long rods aren't a problem as long as they are built right. long rods are sometimes prefered, hell sometimes long strokes are preferred. it all depends on what you want out of your KA I guess. for some stump pulling torque, the stock set-up will do pretty good. If its high RPM horsepower, look elsewhere or have some very extensive and expensive work done to your KA. especially if your going turbo.

McAdam