I've heard that the VQ35 engines have headgasket sealing problems under boosted conditions. I want to boost my G so bad but it only has 570 miles on it and I dont want any problems to occur. I got this information from a well know tuner. Some of you may know Jeff Evans. He tuned my turbo civic hatch that I had with awesome results. He said he has seen it and also read it in many G and Z forums. Said at around 9-10PSI the head gaskets give because the block and head are made of dissimiliar metals. How true is this?

 

you mean the block and heads are not made of aluminum?

no I think that part is wrong, but at about 13+psi it does seem to happen on people who drive their cars hard with that much boost

 

This is not true, both block and heads are of aluminum. But, as some have said, you need a built motor to go much above nine or so PSI.

 

So would I be safe on 8PSI? I'm probably going to go with the Greddy kit although JE is a nice kit its very pricey. Besides, I installed a Greddy kit on my friends GSR and the fitment was A++++.

 

you're doing a greddy TT kit at 8psi (stock is 5.6 right?) without a built block?

 

Please don't just jump into the FI world right away. Do your research first! I hate reading about blown motors.

Apparently, you asking that question means you haven't done much researching. Also, please go to my350z.com. Their forced induction section is massive.

NOTE: Greddy Kit is not complete. It needs several items to run safely. That is why the other TT kits are a little more expensive. Not one single kit is perfect out of the box.

 

Most oem V6 engines are designed with a ~~ 30% reserve to increase the average driver service life up to 200,000 miles.

As you delete this reserve, engine life falls depending upon how often you stress [rpm load etc].
Correcting for density and parasitic drive losses, each psi yields [6.8% gross or 5% net]............with superchargers you have to make an extra 25-40 HP to turn the supercharger........this never shows up on dyno but the engine is still creating it. Why 6 PSI [density corrected inside plenum] is considered the safe limit for LONGEVITY without internal mods.

Longevity means you might throw away 100,000 miles in the conservative supercharging process. Superchargers wear and need rebuilding frequently.

Always budget for a new engine just in case unless you spend $7,000 to strengthen the internals.

 

Very interesting! How would turbo figure into this? They draw no power from the engine.

 

What do you mean by "reserve"? How do you quantify as approximately 30%?

I mean if a seal goes, it goes, right? Are you talking about loss of metal on internals over time?

 

I already had a turbo hatch. So I'm not new to the FI game. I'm just new with the Nissan game.