Turbo causing rods to be rebushed?

[Light]

The title really explains it all, when I removed my K1 Tech rods from my engine the wrist pin end needed to be rebushed because they are .002" out of whack on one side.

My question is what could have caused this? The man whom I took to get my block work done thinks it's because of the turbo. But I haven't seen this anywhere in any KA-T threads.. anywhere. This will be my daily driver (although at 300ish whp) and I really don't want to tear it done again. For a while.


Any clues?

[blingcommander]

could be hammered from detonation? i'd be checking the main bearings too...

[Light]

The whole engine is apart, the main bearings were flawless. It was just those small ends. I think the big end was a little out of round but not by much. I was told that's what it could have been but the pistons are relatively unscathed. The bottom of one piston is a little burnt but I found a broken oil squirter.

[PoorMans180SX]

Sounds like the K1 rods were just not up to par.

[Light]

I haven't heard anything bad about them, i was told they are good rods. You would think for somewhere around $500 (although cheap) they would still be able to hold up against a turbo.

[AceInHole]

The shock wave from knock won't always damage the piston or plug, but it will still generate extremely high pressure. Detonation can range from barely audible pickup from the knock sensor to completely destructive, and everything in between is fair game.

Not saying that knock is what damaged your rods, but I wouldn't discount it either.

[Tower240sx]

K1 rods are mediocre at best, made entirely in china and finished in Gardena CA, the bushing was probably the wrong alloy and deformed trying to decelerate the piston at the top of the exhaust stroke, if you pressed the bushings out, were the holes in the rod elongated aswell?

Knock damage to a piston pin bushing usually shows on rods at least and usually mains also...not to mention it should show on the top of the piston if it's that bad.

[slidewayzagain]

Throw direction of pistons reversed ??

[Tower240sx]

that would just be loud as far as I could guess

[Light]

What do you mean by that?

[Light]

I wouldn't imagine Eagle is much better then? I don't have the money to drop on Crower rods.

[Tower240sx]

To the best of my understanding the wrist pins are offset so that the pistons slap less to decrease NVH... there may be more to it though

[Def]

Did it look like things were getting well oiled up there? If it was, probably just a substandard materials problem.

[Light]

It is too late to tell now. I may just buy some Brian Crower rods seeing as how they only cost $400. Anything that cheap makes me cringe however.

[Light]

I'm also wondering how a JWT tune can be off enough to cause detonation. There is an AEM A/F gauge in the car it would be hard not to notice something like that. Although I have heard of those gauges reading + or - 1 or 2 afr's.

[Def]

I'm also wondering how a JWT tune can be off enough to cause detonation. There is an AEM A/F gauge in the car it would be hard not to notice something like that. Although I have heard of those gauges reading + or - 1 or 2 afr's.

Your base timing set spot on? Tune is only good with base timing correctly set.

[veilside180sx]

Eagle and K1 come out of the same factory, and each respective company does the finish work from what I recall.

I have yet to see a BC product that I was impressed with.

[Matt93SE]

I'm also wondering how a JWT tune can be off enough to cause detonation. There is an AEM A/F gauge in the car it would be hard not to notice something like that. Although I have heard of those gauges reading + or - 1 or 2 afr's.

I have a JWT in my Maxima and I MUST run 93 octane and retard the timing 2deg before stock base timing. (i.e. stock is 15 BTDC, I run it at 13 BTDC.) Any more timing or worse fuel and it knocks when it's above 70 deg. I usually wind up just putting my stock ECU back in during the summer to reduce issues.
So yeah.. a JWT tune CAN suck that bad.

[Light]

JWT said set stock timing. Maybe it wasn't, I don't know.

Now I'm seeing all these products I thought were good now are terrible?
Since when is JWT and Brian Crower terrible?

[Def]

BC has never had high quality stuff. Maybe over at NICO they're the bees knees, but never really heard a ton of praises for their overall quality control and initial design on most items.

JWT is good IMO, on some things more than others, but no company is perfect. People like super high dyno numbers, but they want a safe tune - those things are mutually exclusive, so it's a balancing act for a mail order tuner to get a "safe" level of timing but still make good power. It's not really a "plug it in and go" thing, as you do need to verify you're not getting knock, and if you're using the engine in a really strenuous environment, it might be a good idea to bump back the timing a hair.

[Light]

I thought Brian Crower was always good. I suppose that there is no safe bet until I drop the money on something expensive like Pauter. Are the BC's at least better than the K1's? I don't want to put this in my engine, rip on it for a while (daily/race car) and find out in another 15,000 miles I need to tear it down again.

well he said to set timing at stock and I sent him the ecu number so I guess I'll go with that and get a knock sensor. Will I be able to detect it without load?

[Light]

In addition, speaking of detonation, how big of an intercooler would suffice for 300whp range? I always thought the on I have is a bit small. From memory, I'd say its (l,w,h) 20 x 2.5-3, 6.

[Def]

Sounds a little small, but probably not bad for street usage and whatnot. If you're using it on track, then I'd get one a little larger.

[Light]

So what does anyone suggest? For street driving and occasional heavy racing, should I keep those K1's are spend the extra mile on something better?

[Light]

Resurrecting an old thread,

I've been emailing JWT, and they say it should be about 11.25 to 11.5 A/F at full throttle and good boost. Does this sound any where close to correct?

For reference:
13.5-15.5 at idle
12-13.5 during open loop?

I guess that would be higher rpm just not full throttle on the last bit there?

Regardless, this all seems pretty lean.

[Light]

Bump?

[Def]

Low-mid 11's is right at WOT/boost.

13.5 is too lean to run for anything above a few psi.