stephenlc

iTrader: (1)

I couldn't believe this when I saw it. You can buy brand new 350z pistons and rods for under like $150. Are the vq30 internals stronger than the VQ35 when it comes to pistons and rods. And the crank is a little over $500. I was just thinking about going with the crank and rods though. Get them shot penned to try to strenghen them. I am going to look up OEM maxima internal parts.

http://www.trademotion.com/partlocat...03&catalogid=1

Nealoc187

iTrader: (23)

I was having a discussion last night with BriGuyMax (old school .orger who now has a 350z) some 350z and G35 guys have been throwing rods at like 350whp... and these are cars that are well tuned using emanage and J&S, datalogged runs and such that show no timing or fuel starvation issues, it appears they are just overpowering the rods. On the other hand there are others who run 450+ to the wheels daily (I've met one such person) and have had absolutely no problems. So the current mode of thinking in the 350Z/g35 community is that there may have been a bad batch of rods produced at some point. So there are people working on compiling the data to figure out the production dates of the rods which have failed, and see if there is common timeframe between them, in contrast to the myriad other cars who are running tons more power, and having no problems at all.

mtcookson

iTrader: (2)

From what I've read its the open deck design from stupid emissions bs. When pushing higher amounts of power the cylinders actually start shifting which causes stuff to go out of whack and the engine blows. That's why some company has come out with a kit that either makes the open deck design stronger or you put in some sleaves for a closed deck design. I can't remember what it was they did but it helped out the engines a lot.

stephenlc

iTrader: (1)

thats the AEBS kit and its 8 grand plus. SGP and many others have said that the stock sleeves shoul dbe good to 700 whp. I was just going to shot peen some brand OEM rods but I wanted to know which ones were stronger the VQ30 or the VQ35. It seems that a lot of 350z guys are throwing rods, and I have never heard of a maxima throwing rods. So I might just get new VQ30 rods and pistons and install them on low milage engine from the junkyard. But Mardi and Hal, and Even Dixit seem to be making 450 whp+ on stock rods and pistons. So I might not through thr trouble of breaking down an engine. Mine is a dialy driver though......

IceY2K1

iTrader: (3)

There are a couple possibilities....

One weakness is the VQ35 bolt. Nismo recommends this upgrade to reliably rev to 7200rpm. A lot of these guys are running 7100rpm with stock lower ends. I don't think anyone has had this fail, but a concern.

Second is timing. VQ35s are very aggressive compared to VQ30s due to their extra large capacity cooling jackets in the heads. This means more detonation and worse preignition prone, if combustion chamber temps are out of control.

Third is piston speed. VQ35s long stroke means they are running much faster pistons speeds then the VQ30. This is extremely hard on rods and when pushed with boost can easily exceed OEM strength at almost DOUBLE the factory power levels.

There are more, but the VQ35 cold coined vanadium rods are stronger then VQ30 rods...just stressed more. And when you pair that up with a TT kit that makes HUGE amounts of torque at low RPM vs. our single turbo, you're asking for it.

Put VQ35 rods/crank into a VQ30 with proper height custom low CR pistons and they'd handle 450-500whp range.

stephenlc

iTrader: (1)

will the vq35 rods fit on the vq30 crank and the vq30 pistons fit on the vq35 rods? Compression after this? If you used the vq35 crank and rods, you would need 7:5:1 compression to make it 8:5:1 in a VQ30?

IceY2K1

iTrader: (3)

Rods and crank must be from same origin. The small ends of the rods are the same, but the large end and crank journals are not.

Not sure on displacement, I've heard about everything under the sun.

Nealoc187

iTrader: (23)

Timing isn't the issue with at least some of the broken motors, the latest guy to throw a rod was running J&S and no knock at all was detected, motor blew right at the torque peak 4400rpm and he was putting down about 350 emanage regulated hp. Obviously something went wrong though.