Hey all, just picked up an '05 Z 6mt Base a couple weeks ago. I am a transplant from the Supra TT community and have quite a bit of "tinkering" & fab experience when it comes to FI. Anyway, not only are the looks of the Z eye catching but I do believe that once this community gets more experienced in the FI arena and more products to support FI become available, the VQ35 should make an awesome platform. I've read a lot of post on here from those who have experience with FI, be it good and bad, and hope that I will be able to contribute as well.

The plans for my Z, which is not a daily driver rather a weekend warrior, is of course FI, mid to high 400whp on stock internals, RELIABLY. Looking at running the Turbonetics kit with E-Manage Ultimate and custom return style fuel system (plus some other stuff I'm probably forgetting).

First thing to address is strengthening the stock internals. Not only to support more power but to also overcome the increase in cylinder temps. I think this is the biggest problem associated with failed internals, aside from detonation. These internals were designed to operate within a certain temp range on a NA motor. Once exceeded this will cause significant weakening and possible over expansion (higher stress due to tighter tolerances) of the component. As we all know s**t rolls downhill, so a weak piston won't be as tolerant to detonation or even slight "pinging" as it would have been while operating within its temp range. Easiest way to overcome this is Deep Cryo Tempering. $500 to have the complete engine assy done, right off the bat I'll be looking at up to a 150% increase in strength and durability and an increase in density which will allow heat to be dissipated more quickly and uniformly.

To combat higher temps even further I'll be going with a DIY H2O/Methanol injection system. I have the plans for the system that I ran on my Supra and it worked flawlessly, albeit it was a 2 stage system designed for 20+ lbs. boost. Won't need this much for the Z!! Funny thing, when I first ran this on the Supra I was getting below ambient intake temps but only marginal hp gain. So I knew it was doing its job of cooling the charge, but I just didn't understand why the power wasn't there like it should've been. Come to find out (simple physics) the addition of the H2O/methanol being injected in the intake was displacing some of the charge. Still below ambient temps but less of it going to the motor. Simple solution: A bigger f***ing intake tube Now granted I was'nt looking for some astronomical gain in power but suffice it to say rwhp did go up a bit mainly due to less timing being pulled. Think I'll run the system off the e-manage aux map output to cut down on some of the sensors. Total cost of parts shouldn't exceed $250-$270.

Last but not least, homemade race gas!! Quite frankly, at these power levels one really shouldn't need it, especially running h20/meth injection but extra insurance never hurt nobody. Right?? Simple mix should bump octane up to 101: 70% Gas (conservative 93 in GA) & 30% Xylene w/5oz 2-stroke motor oil added per gallon of Xy.

I'm sure more stuff will come along during my planning stages but based on a lot of your posts, I see this as a viable plan of attack to run into the high 400's on stock internals, again RELIABLY.. Please post comments, opinions and constructive criticism.

B

 

If you have the motor apart to do the Cryo tempering . WHy not just build the lower end to hold the high boost you want to run ?

 

Cost, $500 compared to 6k assuming it is DIY. Which from what I have read he plans on doing.


I like this, Keep us posted.

BTW do you mix your own race gas at the station while pumping?

 

Hey booger, again I'm kinda basing this off of other peoples experiences here. I've read where guys are running successfully in the low to mid 400whp range on stock internals with no problems, YET . In my mind I don't see warranting a $2k+ purchase for forged internals and engine work when I'm shooting for 60-70 additional whp above what others are running successfully on stocks. Now I could be wrong and blow this motor, at which point there's no other option other than forged internals. But hey, it'll all be for the betterment of the 350Z FI community.

 

sounds like you have done your homework, but still have to agree that even with cryo-ing the bottom end you will still run into fatigue over time. once you pull it apart you will be able to see just how small the rods are and make the decision then if you like. even a set of carillos (costing less) would be of great benefit. i bent 5 rods in my motor before i pulled it apart to do my bottom end with an ati setup. the rods were visibly bent not just thousands of an inch off!

 

SUBSCRIBING did this on my bike was thinking of doing it to my car as well

 

very nice to have you here.

 

rxtrom, you can mix at the gas station but it becomes a little more inaccurate (and cumbersome) doing it there, as you don't know what your ratio would come out to be. In the past I usually premixed in a 55 gallon plastic drum and filled up at home using one of those pump deals from Summit. If you bounce back and forth between gas and you're filled with regular pump I'd run that tank dry and fill up with the mix afterwards. That way you know your mix is consistent.
OR, what you could do is premix just the xylene and oil in a gas can, run your tank dry, and then fill up at the gas station (if you have no place to store gasoline at home )
Cool??

B

 

overZealous, point well taken bro I have not been in the motor yet (only 1500miles on it) so I'm sure under further scrutiny I'll come to a clear decision. I still have faith in cryo-ing though. What was the final verdict on your motor that caused the bent rods? Was it possibly the tune, detonation, hard driving, combination of all or was it just component failure??

 

Ya I was talking about bringing a pre-mix and then add it to the tank and then monitor the gallion going in on the pump. Anyway, having a 55 galon tank at home does seem a bit better. My only question though. How do you get the 55 gallons of pump gas to your house.

Bribe the tanker guy??

 

i was running 15psi on the ati with stock internals, hahahah. so i guess i am not one to point fingers. but i wanted to blow mine for a good excuse to do the built motor. i think it was a combination of just overstressing the parts and possible light detonation. i had 4 pistons with broken ring lands also. funny thing though, the motor sounded perfect with the exception of a little smoke. one night out driving the car really hard through all the gears did it. woke up and it was blowing a little smoke. a comp check revealed 2 down at 140psi with the rest at 170. TIME TO REBUILD, lol.
but honestly, when i got it apart and looked at the rods, it looked like it should have come from a lawnmower.

 

I was welcomed from the rotary com so im sure you will be met with the same.Good to have ya here.Now down to buss what did you do with your supra?LOL anyway i think you will realize that the vq will probly never be the 800 hp beast the supra good be.

Good idea on the cryo but if i pull this thing apart im not going to second guess.

 

Welcome,

Water/Methanol is a great idea, and you are right that by itself, it doesnt add power, but allows you to run more boost or more timing advance safely.

Regarding cryo treatment. The labor involved in pulling the motor, tearing it down, and sending our parts for treatment and then reinstalling everything....may be cost prohibitive. I'm in the "if you tear it down, just put forged stuff in there" camp.

The parts you need are $2000 or so...depending on which way you go...plus machine shop labor.

Many of us have safely gotten mid 400whp on the totally stock block. So maybe with race level octane, water injection, return fuel system, and a PERECT tune with an eManage Ultimate, you might just pull 500whp on the stock block safely...especially if its a weekend warrior.

Let me know if I can help. Welcome again!

 

I'm all for it, and will be watching your progress as much as possible. I hit 10-10.5psi on a regular basis..almost 5000 miles and I stay on the throttle, even hit 11psi once. I use a 50/50 mix of water and methanol myself and I've had no problems, even with the restrictive G35 bumper! When I get the car back I will have direct air flowing to the intercooler and a vented hood so I'm interested to see how that goes.

 

I like the idea. New idea will push all of us forward.

However, the stock 2JZ GTE motors are very very strong out of the box. I would say much stronger than our VQ35. Therefore, if we want to FI VQ35, I belive we need to do something to the stock engine to be able to run them with peace of mind. Run lower CR and a good set of piston and rod will be great. I mean, if we start with this then we become similar to the set up of 2JZ GTE or Porsche turbo which have strong and reliable engine.

 

subscribing... interesting idea. i am excited to see what you come up with.

 

Hey all, thanks for the welcomes and hospitality. Glad to be a member here.

Sharif, I will be doing all the labor myself (other than the cryo of course). Good thing about working on that damn Supra for 5 years, I've accumilated a lot of tools (being an Aircraft Tech helps too ). Anyway, as mentioned earlier my car's not a daily driver so down time's no issue. You seem optimistic that I'll be able to pull 500whp safely with this set-up so I at least feel like I'm headed in the right direction. I really do have faith in cryo, as I've used it before. I do understand that for someone who would source the work out to a shop, the cost may not be beneficial unless they were getting built up..

tonio, I see you're in GA as well, AND running FI. Cool Bro...Once I get further along in this I'll definetly need to hit you up for some recommended shops/tuners.

 

damn I didnt even notice you stay in atlanta.. what part? Any time you want help with anything let me know, I'm constantly working on my car in the garage so I got a few tools and things around the house.

 

Just get an APS kit, Ive hit 11psi quite a few times. No pinging, detonation or extreme cylinder heat noticed. I keep my octane around 95. Im tuned for Cali 91 @ 8.5 psi. Since we've gotten some mixed weather lately, when it gets cool i make a lot of power. Good luck, I seem to think some early engines are different. Some seem to make power and others just can't seem to handle it. Hopefully the 05's stronger rods and pistons help people out by allowing more strength to run the boost safer and more reliably.

 

Welcome (i had to say ot, everybody else was )
any reason you are planning on going with a single turbo vs the twins?

good luck (I'm also in the camp of, if you are gonna pull the motor apart, through some forged internals in there)

TODD