It's good to hear from you....outstanding write up. Mine is running a little rich as well, but I'm at 3500' so that is another factor to play into things. My fuel economy is never more than 24mpg on the highway, mostly 22ish and 14 or 15mpg in town. I attribute it to my driving style as the best I have gotten NA was 26mpg hwy and 17 around town.

^ wtf? are you thinking lean? all running rich will do is eventually foul plugs and o2 sensors. if he were running 7-8 to one then MAYBE he would have to worry about washing the rings but 10.5 isn't going to do any real damage. All he is doing right now is wasting fuel and losing power.

Jumping in to clear the "air". When Mike's Z left California it was tuned for high 10s and low 11s. His environment (altitude, pressure, humidity) will attribute to changes in the tune. With that being said 10.5 under WOT on a high compression engine not intended for boost is perfectly safe. On the other hand if your idling and cruising at 10.5:1 AFRs then there is cause for concern!

Another thing to remember is air is 500x times lighter than fuel so when you first hit the throttle you'll see transient fueling enriching quite a bit to account for the huge rush of air entering the cylinders. You may see it dip down but otherwise it will stabilize.

Brand new forced inducted vehicles, for example GTRs, EVO Xs, etc., have a nice soot build up on their tips and the bumpers get "coated" black even after a minor amount of miles. This is with them having two sets of cats on them still. I think Mike's post was taking way out of context and the way it was written makes it sound like something is wrong.

Correct -- thanks for clearing this up, Seb, and I apologize for any confusion caused. The black coating is nothing new. My Dad's GTR has a similar buildup but not quite as dark, but that is to be expected. Also, the exhaust tips with the Nismo are recessed due to the bumper design, so it's gonna get black faster than a standard Z rear bumper would.

Anyway, the 10.5:1 AFR is a stable reading while under WOT and full boost. Idle is right where it should be: 14's. I'm not concerned in the slightest -- you and the F.I. crew know what you're doing, and I would hardly peg 10.5:1 as off the deep end! That being said, I think 10.7-10.8 would help mileage, but I'm not sure if that's pushing the envelope too much. The tune is definitely rock solid. Another note with mileage, I had my turbo Mazda3 tuned to run mid 15:1s when cruising at highway speeds, which really helped mileage and didn't pose any issues on that particular car, but I don't know the ins and outs of how the Z would handle that.


Any other questions, post up and I'll try to answer them.

P.S. Yeah I took the Z34 PA plate :p
P.P.S. The F.I. oil cooler setup is incredible! I never top 180, even on 95 degree days. Granted, that isn't track driving, but I was hitting 220 before I made the switch, and that was N/A!

The cool thing is that you can get that coating off in 5 minutes with a metal cleaner. I do it once a week just to make sure they look their best and will long term.

I'm not so sure it would. I suspect the majority of your driving is in closed loop cruise fueling mode where you are targeting stoich (14.7:1). You are only going to be getting that rich when under high boost. And if you are under high boost, then there is no point in thinking about fuel mileage.

Now, I have read about people lean tuning for closed loop mode (e.g. 15+:1). That's an interesting idea. It actually works OK from a power output standpoint, but I think the potential issue is the heat. Inevitably, some fuel is not burned, even when targeting stoich, and that fuel is being vaporized and absorbing heat. Take it away and that's more heat the block has to deal with. Not good on a VQ.

Thats not how it works but sure.

Time will tell . 7-8 to one A/F will only bog your engine with black smoke. Happened to my 98 Supra TT many times and finally kill the rings at about 20K miles. But 10.5 : 1 under full boost is likely OK, as long as you don't idle and running part throttle at this A/F ratio.

Actually, it is. When I drive my TT Z around, the AFR gauge is almost always reading near 14.7 because most of the time I am not accelerating and moving into a richer area of the fuel map. As for lean tuning cruise mode, just do a google search on that and you will get educated.

But if you think you have a better understanding, please, do enlighten us. :ugh2:

My thinking is more to cut down a tad on in-boost consumption, since there is an incredible volume of air/fuel going through the cylinders in that state and even a few tenths of a point are likely to make a tangible difference. I'd probably go from 1.5mpg to 2.5mpg under load LOL :roflpuke2:

And on a more serious note, the only thing I really want to adjust is the loudness/drone of the exhaust, which can get tiring. Anyone up for a non-res & 18" res swap out?

Actually it's not how it works, lean fuel mixtures do not make the engine run hotter because there is less fuel vaporizing and sucking heat out of the motor, it is because a lean mixture burns more rapidly which means peak cylinder pressure is reached earlier in the stroke forcing the engine to fight itself while retaining a hotter mixture of gas in the engine for a longer time, in a rich burn situtaion the fuel will still be burning exiting the engine which tends to increase egt's but is not as hard on the engines cooling system. the latent heat of vaporization is less important until you start getting into alcohols and nitro mixes that really can cool the entire top end of the engine just by evaporating.

As for the closed and open loop stuff, what you are suggesting is already in place in the ecu, from the factory the car tapers from the low load sites which are 14.7ish and as load and rpm increase the afr tables drop in the ecu. If tuned properly your tuner should only be adjusting the mid and high range/load sites to keep it rich enough to prevent detonation, the low end only basically needs to be tweaked to fine tuned for changes in maf size. As seb had said in his earlier post if you were running 10.5-1 at idle that wouldn't be a good thing because it shouldn't be doing that. The only other time the low load sites should go richer would be if there is a tip in lean issues that can't be tuned out some other way.

I think we are talking past each other, and not being very accurate. I have only been talking about closed loop mode (i.e. targeting a stoich mixture of 14.7:1).

First, the relationship of flame speed versus AFR is a curve that peaks below 14.7:1 then drops on both ends. So, while moving to a leaner ratio from a very rich ratio will speed up flame speed, that only holds true to a point around 12:5:1. After that, leaner = slower. I was talking about ratios above 14.7:1, where additional air will slow the flame speed down, and not speed it up as you suggest. See, for example, discussion here: Spark Timing Myths Debunked - Spark Timing Myths Explained:: Application Notes ("At about 12.5 to 13 air-fuel-ratio the mixture burns fastest. A leaner mixture than that burns slower.")

Also see the same concept in graph form:
http://i289.photobucket.com/albums/l...%20car/afr.jpg

Or here:
http://www.max-boost.co.uk/max-boost...vs_density.png

As for the lean burn on cruise, the car is targeting 14.7:1 in closed loop, cruise mode from the factory. People have experimented with "lean tuning" i.e. targeting higher than 14.7:1 in closed loop, cruise mode in order to increase fuel efficiency.

For anything under load, I am not about to try to go a bit leaner than what my turner suggests to save some fuel. That extra fuel helps with cooling, which helps with knock prevention. I would rather save my engine.

Been holding off on my review because I wanted to post some vids of the insane power but drag day is a week away and track day two and a half. So I decided to do a review with some pics followed by the vids in a few weeks.

Where to start? Maybe with a simple summary, “wow”.

And I don’t mean wow just because of the raw power. Lots of superchargers and turbo kits have power. But what I find astonishing is how effortlessly the Fast Intentions twins bring on that power and how clear it is to me that if Tony and Dan built a system for themselves this would be it; it is not just a bunch of parts. It is a commitment to quality and performance fueled by their honest and true passion.

Presales:

When I first contacted Fast Intentions I was expecting a series of email exchanges. I’m not a turbo expert so was ok with that. I had lots of questions and didn’t want to waste their time by asking they educate me on my time. Tony would have none of that. He told me that he would rather talk about what I wanted to accomplish than communicate via email.

I’m glad he did. Before I sent my deposit we probably spent three hours on the phone over the course of two weeks with a few email clarifications along the way. Tony’s main concern was understanding what I wanted to do with my car both short term and long term. Was it a daily? Drag? Track? Was I going to build the motor and push in to the 700 and 800 hp range? How did I like it stock (to make sure they didn’t make things I don’t like worse).

I had done some research and thought I knew what ‘parts’ to put together but after talking to him it was clear that I didn’t know a thing. He suggested downsizing several items and eliminating others all together; all along the way educating me.

What I Ordered:

- Twins w/Garrett GR28RSR turbos
- Bosch 650cc injectors
- Upgraded fuel system (ended up being the FAST-500)
- Test pipes with 2.5” non-res catback (100 cell inserts)
- Specialty Z 6 puck and flywheel combo
- Setrab 32 row oil cooler
- Tilton CSC
- HKS Racing M Series spark plugs
- Whiteline rear diff bushings
- Uprev w/three tunes (5 maps)
- Full installation done by F.I. including the eBoost2 boost controller

Why am I including the non-turbo items? Because Fast Intentions understands that turbos don’t exist in a vacume. Our cars do not come stock with forced induction. Some parts are not meant to be pushed to 600 hp. Of course they will sell you a ‘kit’ but at least look at what else they make available because it is made available because you –will- need it.

I placed my order will full confidence that the car would be returned to me and perform –reliably-.

Post Sale/Post Delivery:

Tony knew I was driving my car home which was 2000 miles away...through a desert and over the Rockies...in the heart of summer. He checked in with me every day to make sure things were working. I felt like if the car died at 3am in the Mojave he would have gotten in his GT-R, grabbed Dan and his tools and been there. I said felt...of course I would never have expected that.

But my point should be clear; Tony and Dan care just as much about your car as you do. They 'get it.'

Build Impressions:

It is my belief that people tend to have a very narrow focus of view when making comments like ‘the build quality is excellent’. They seem to look at weld quality and make broad stroke statements based on them. I am not a build quality expert but it is hard to imagine how what I received could have been of any better quality; even down to the seals being o-rings instead of gaskets. Just amazing.

Some people have commented that the Fast Intentions setup is not self-installation friendly. I’m not going to disagree. But the reason it is not friendly for most of us is that it is designed with efficiency and performance in mind over many other things. “Oil filter is in the way and routing around it will decrease efficiency…so move it.” And oh by the way, “Lets use milled parts for the relocation.”

Ok, removing my washer fluid reservoir was a surprise! I had a good laugh at that. But really…washer fluid or perfect placement of the intakes? There is still room in the area so I’ve decided to have a custom aluminum reservoir made. But you can just as easily get a small plastic one too. In the end I appreciated that Tony and Dan have their priorities straight!

It’s interesting because ‘efficiency’ turned out to be amazingly stealth. At shows I get a lot of people coming by to check out the engine bay. They are almost universally shocked to see what looks like a stock bay with polished intakes. I’ve had a number of people pull back and bend down to look at the intercooler because they thought my car wasn’t ‘that’ car.

Insanity:

I thought that I was crazy when I swore the turbos began to spool at 2500-2800 rpms with full boost around 4500 but someone else posted their thoughts just a week ago and said the same thing so I’m going to call it confirmed. These things spool fast, come on hard, and don’t ease up all the way to redline. And against Tony’s advice…they’ve seen it in several gears.

I think the way the power comes on is the biggest surprise. I’ve driven several boosted cars before and most of the time you have to use the throttle to keep boost out of turns. That and there is that ‘turbo surprise’ at some ‘magical’ rpm. Not here. In fact the power comes on so quick that I really have to be careful when coming out of turns. It’s like driving a new car and I love every minute.

Bottom line is that if there was one thing missing from the Fast Intentions setup it is new tires. They need to be wide and sticky. It isn’t hard to spin the OEMs in third.

Oh...exhaust. I have test pipes to non-res catback with 100 cell cat inserts. It is not as loud as a Harley but it is no kitten. I'll post vids of the sound after drag day. It is deep and...awesome. I got to hear it as a bystander a few days ago when I gave the keys to a friend. I might do that on a regular basis because it is the only way to really appreciate the tone. However, if you need to be mindful of the neighbors at 7am you might want to think about resonators (but full cats are a no no).

Bottom Line:

The wait is worth it and the value is excellent. There really isn’t any better way I can close the review.

--Arrvaxx

Arrvaxx’s turbo ‘break in’ procedure. Or, “How I beat the hell out of Tony and Dan’s creation and survived. Or, "How I gave Tony and Dan a head full of gray hair!"

***Fyler update***
 

NEW FYLER UPDATE...

http://fastintentions.com/images/370z/370zflyer_01.jpg
http://fastintentions.com/images/370z/370zflyer_02.jpg
http://fastintentions.com/images/370z/370zflyer_03.jpg