VG30DE Rebuild info requested

[Kyoso3z]

Ok guys, I am wondering for those that know or have done themselves, what is the optimum HP that can be attain by the VG30DE (NA now) platform? Rules: has to be a daily driver and reliable, with little to no adjustments. What are the best but also cost effective upgrades needed. I don't mind spending more money if the gains and reliability are worth it. And before anyone says it....."why spend that money for such a small amount of HP, why don't you go turbo?" ; just save that statement/question for another guy please.

[McShanks]

The NA VG30DE is already a pretty powerful and efficient engine for its size and age, so don't expect to get a whole lot more out of it without putting a whole lot of money into it. If it has to be a daily driver and reliable, your best bet is to stick with mostly OEM (non-Chinese) parts. Cut out the throttle body coolant lines, the air injection system, the EGR system and the catalytic converters, keeping in mind your local emissions laws. Here in Indiana where I live, when a car is 25 years old, it becomes an "antique" and emissions equipment is no longer required.

An ecu reflash (Jim Wolfe, CZP, and Z1 and others have good ones from what I hear), will cost a couple hundred and open up some power at little detriment to reliability. Some port work, and a good exhaust will free up a bit of power, along with an underdrive pulley system. All this should put you around 200-ish at the wheels, maybe a little more.

Now if you are willing to spend some cash (not a crap-ton, but maybe $2-3k) , then one option to consider if you are planning on a complete engine rebuild, is E85. I and my friend have done extensive research on E85 conversions, I have read technical papers regarding various E85 testing, technical papers on E85-compliant materials, etc. Although I am not an expert, I do have a degree in mechanical engineering from Purdue University with a focus on thermodynamics and (jet) engine design, and have consulted with experts at Z1 motorsports regarding E85 conversions specifically for the 300ZX. It is very doable, and has been done with both the TT and NA with good results. At a bare minimum, you will need to make the following changes:
-A new fuel pump (AEM makes on for E85 at about $120)
-New injectors (about $500 for the 370cc E85-compliant set from Deatschwerks)
-New E85 fuel injector line to replace the old rubber fuel lines (maybe $100 total).
-ECU reflash ($200 to $400-ish; let your programmer know EXACTLY what changes you are making for best results)
With this setup, you can run E85 ONLY (it is NOT flex-fuel capable without a standalone chip and a whole mess of parts) safely and reliably.

Now, you can take this further while still maintaining reliability and drive-ability with the following (still E85 ONLY):
-A set of 12:1 or higher compression ratio pistons (reliably up to about 14:1 depending on your local E85 quality; more compression = more power; about $800 for Wiseco from Z1)
-Upgraded fuel rail (varies in price from a couple hundred to over $1k)
-Port/polish intake manifold (practically free if you do it yourself)
-Headers, X-pipe, good 2.5" exhaust ($1k+ depending on what you get, although it is getting harder to find the good quality NA headers)
-Zemulator, Nistune, etc custom ECU tuning and dyno ($500+ for the tune, dyno days aren't cheap, either)

All of the above allow you to keep stock block, crank, heads, cams, valves, etc, and put you in the 300 RWHP range (depending on the quality of parts and tune) with the reliability of a mostly stock engine. You could dump even more $$$ into overboring, JWT cams, standalone ECU, bigger valves, custom dry sump oil system, top feed fuel injectors and rail, lightweight flywheel, lightweight drive shaft, custom intake, etc, but you are starting to talk big $$$ and less reliability.

Everybody has their opinion on this, and there will definitely be some people who will try to scare you away from E85. Most of the issues people had from converting Z's to E85 were many years ago before E85 was fully understood. Here are some of the issues people had:
-Injector failure (OEM injectors not rated E85)
-Pump failure (OEM pump not rated for E85)
-Fuel line and o-ring failure (injector O-rings and rubber fuel lines not rated for E85)
-Issues with tuning and idle (people were not getting the right air/fuel ratio before due to using wrong sized injectors and lack of reflash/tuning)
-"Gunk" buildup and dirty/clogged injectors (using old rubber fuel lines and not cleaning fuel system; E85 will clean the old crap out of the system)
-Variability in E85 fuel quality (this is still a potential issue, you can read up on what companies offer consistent and good quality E85)
-Lower MPG (E85 has a lower air-to-fuel ratio, so requires more fuel to burn, but is typically much cheaper than premium fuel; usually ends up in a wash as far as cost per mile, but you get more power)
-Moisture absorption (E85 tends to absorb water, not really a problem with our sealed tanks in the Z's as long as your car doesn't sit for months)

Most of these issues have been sorted as I have noted. Here are some of the pros of running E85:
-Cleaner fuel (much cleaner actually, both in the fuel itself and how it burns, resulting in better emissions and better smell)
-Cooler-burning (Can run higher compression and more advanced timing for much more power, 50% or more with the parts I listed above)
-Reliable and growing renewable "green" fuel source (if you're into that sort of thing)
-Usually cheaper (until the recent oil price crash, E85 was cheaper to run despite the lower mpg)

I gave you what I think you are looking for, so I hope this helps! Let me know if you have any questions.

*Disclaimer* Although I tried to be as accurate and correct as possible, I do make mistakes. It only happens about once every 4 years or so, but it does happen. Do your research before making any changes to your car! If I made a mistake or missed something, please let me know and I will correct it!

[McShanks]

Oh, I guess I should have put that my friend and I are working on doing the E85 work now and plan to be ready to drive the car by this summer. I am still working on parts and development for the VH45 for my car, although the E85 work for his has me intrigued and I am focused on that at the moment. A full write-up will come when it comes.

[NolimitZ32]

For all things NA that you want to know search for honad's build thread on this forum, I believe at the end of the whole process he made something like 220whp

[Kyoso3z]

McShanks, what a perfect response and extremely informative! I really appreciate you taking the time to write all of that down and sending it my way. I really like the idea of the E85 and will be doing more in depth research to it's high probability in my future rebuild. The money isn't really a issue but I just didn't want people responding by trying to build a track car and or some crazy unreliable monster. But at the same time, I would like to keep the build half way manageable since I have a much larger and more important build going on. But I'd like to have a nice decent daily driver Z on the side while I build my big one. Any more info that you think of, let me know. I'd love to hear more from you and anyone else with experience of building a sound platform on the VG30DE. Looking to start my build on this 300z around spring, so I have some time to finalize everything.

[McShanks]

No problem, just figured I would pass along the research. Although this type of work has been done to the Z's, it is very hard to find for some reason...

By the time you get started, we should be mostly done. He is in the rebuild stage now, which has been on hold due to the holidays. Should be getting moving here after New Year's. Planning is everything, and don't be afraid to try something new! You can always get another engine of you have a few hundred bucks, used NA engines are really cheap right now.

Here is a link to a turbo E85 300zx: http://specialtyz.com/blog/?p=1927

And another: http://specialtyz.com/blog/?p=2540

Note that with Turbos, it is much easier to run as a flex-fuel car more efficiently since you can control final compression ratio by controlling boost pressure. Obviously, this is not possible in an NA Z, which is why we are going E85 (or higher-octane) only. You can run it as a flex fuel car safely by keeping compression ratio at 11:1 or lower, but you will miss out on any significant power gains when running E85. If you decide to go the flex-fuel route, you will need a flex-fuel capable standalone ECU (I think Haltech makes one) and preferably an octane sensor if you want to change fuels frequently. But overall you will miss out on power. Pros and cons... :/

Good luck with your build!