KA24DET Connecting Rods

[Turbo 510]

What is the thought on upgraded connecting rods for a KADET? Mine are the stock rods which I have polished, shot peened and added ARP bolts. I am concerned about their durability in a ~20 psi engine. No one I talk to seems to know anything about the rods. $700 a set is alot if the stock ones are fine. If aftermarket is the way to go, what do you recommend and who has the best deals.

[fiznat]

I'm going to be using my stock rods (combined with some forged pistons). I MAY have them shotpeened, but probably not even that. It's my understanding that it isnt boost pressures that destroys rods (that abuse is put largly on the piston/rings), but high RPMs. I dont plan on really reving my engine that high (I wince whenever it gets close to redline), so I think that I should be pretty good with the stock. We shall see, I guess. BTW I plan on boosting about 15psi.

[BoostFab]

I MAY have them shotpeened,

isn't stock rods are shot-peened already?

[Nathan]

Indeed, apparently they are shot peened from the factory. IF I was keeping stock rods I'd probably have them polished, balanced, and then shot peened again. However, Pauter's just look so much nicer

[Turbo 510]

I think the stock rods are shot peened from the factory but after grinding and polishing the casting marks, I had them re-peened. You are right, the Pauter's look so much nicer but the $700 price tag is tough to swallow.

[andrave]

I'm going to use stock rods but my motor will see at most 14 psi, closer to 10 psi everyday (and even then I may turn the boost for street use).I'm siding with the thought that its usually revs that kill ka rods (due to bore/stroke, makes for high rod speeds if you rev higher than 7k) and not boost pressure. I know a few guys that killer rods from revving, none that killed them from boost.

[Turbo 510]

I don't plan on revving past 7K. Before I took the motor out for furthur upgrades, it seemed like it didn't like to rev. Part of the new upgrades include an aluminum flywheel and new JWT cams so hopefully that will change. The DE has a decent rod ratio so hopefully at my revs it will stay together. All of you are right, boost doesn't kill rods it all about the RPM's.

[Nismoguy]

so has anyone on the board run stock rods with big boost? I'm wanting to do the same as the rest. I just want to know what hp numbers are the rods good for? does anyone know? I've asked this question on more that one ocasion and never got a straight answer just "thats what the search button is forthanks

Nick

[MikeMurphy]

From what I understand a finely tuned 12psi car with zero detonation will hold up well. At first sight of detonation however things start to fail.

So, 12psi or so from what I understand, but im dumb.

[trpower7]

Incorrect. Dennis runs 15PSI on stock pistons and rods with a JWT ECU and MSD 50lb injectors. Detonation is the killer. Lack of fuel, bad timing. Stock rods fail because of RPMs, not boost. Pistons fail because of boost but more correctly, detonation. A set of forged pistons and cleaned up rods should be good to at least 15PSI if not much further, but there are a lot of other factors that come into play at that point. It's not a simple equation.

[andrave]

detonation will kill anything though, has that been said yet? I mean on the 240 its not usually the rods that give, although I guess if you had chrome rings, forged pistons, and a metal headgasket they might be...but you can go out and buy your JE pistons, total seal rings, crower or pauter rods, have it all put together by a race shop, and take it out and detonate, and you are still gonna break something... detonation kills.

[scotty-2-forty]

You are right, the Pauter's look so much nicer but the $700 price tag is tough to swallow.

Look at it this way; swallow it now or swallow it later. Any high performance engine builder worth his salt will tell you to "prepare". Planning a turbo install? ... Build the bottom FIRST. Yeah, yeah, yeah, it's not going to give you instant gratification, but good things come to those who wait. Me? I'd rather build a car right than have to go back to square one and spend double doing what should have been done right the first time. Detonation is the killer! Those who've failed to plan, have already planned to fail.

PS - I have Pauter forged rods and CP pistons with Wiseco rings and can speak highly of all from past experience.

[Turbo 510]

I have a very stout bottom end except for the rods. JE pistons, O-ringed block all balanced ARP main studs, Cleaned up rods as noted above, JWT ECU, 370cc injectors, etc. It runs very hard on 16 PSI. I have no doubt that the Pauter rods are stout and you have had no problems. My question is what will a set of stock properly preped rods hold up to, given all things, fuel, timing, etc. are properly set up.

[TrunkMonkey]

My question is what will a set of stock properly preped rods hold up to, given all things, fuel, timing, etc. are properly set up.

no one knows because no one's broken rods in a setup that's been tuned properly.

-demetrius

[Turbo 510]

It sounds like the stock rods will do the job in my case.

[95_240sx]

Oh my god, you are alive., What the hell is going on with your car? Is it finished or what? You still owe me a ride, and I need that IACV back if you still have it.

Rick

[Turbo 510]

I installed the IACV on my engine cause the old one was suspect. It required me to rewire the whole subharness since the connectors are different (oval vs. square). The engine is currently out of the car and the frame rails are getting painted. In addition, I have added 740cc injectors, a cobra MAF, a newly reprogramed ECU, JWT camshafts and a JWT aluminum flywheel. If you check above, you can see that I am concerned about my modified stock rods holding up. The smart thing to do is probably step up and get the Pauter rods but why spend if you don't have to? By the way how do you like your lightened flywheel? Any problems or concerns? Steve does not like them for street cars and advised against it,

[andrave]

what is the biggest injectors JWT will tune for? will they tune for 850's?

[Nathan]

I heard word of them maybe doing a program for 96# hr. msd's. That'd be huge. Right now I know they do up to 4 bar programs for 72# injectors.

[Turbo 510]

When I spoke with Clark at JWT, he said that the 740's were the biggest they did which I think are the 72 lbs./hr. He said that the 740's are on the edge of smooth running at idle and wouldn't go bigger on a street car. He said that the 740's are capable of supporting HP in the low 500 range as long as all other systems are up to snuff.

[3rD GeAr]

i have je pistons and stock rods on my ka24et and have had no problems running 16psi daily running rich. i just got my ecu back from jwt and now its time to get it dyno tuned and raise the boost up to 20-25psi and see how it handles it.