RBRotary

Alright well i recently bought a BNR stage 1 turbo and just broke it in. I'd like to put up the boost cause it says i'm only running 4psi on my boost gauge. I was wondering what i'd have to do to put it up? I know that you have to mess with the actuator but i don't want to do anything to ruin my car.

The only mods i have done for my car are Full Turbo back exhaust, emissions & block off plates, BNR Stage 1, 255 Walbro fuel pump and i'd say thats about it. I might be forgetting some but if i remember i'll be sure to throw them in.

So any help would be appreciated and any comments help too (suggestions as well)

oh and what should i set my turbo timer to? lol

thanks

RotarySupra

iTrader: (-1)

i would recommend a boost controller and your tt,i'd set it to the way you drive.if you drive it hard set it to like 1 min.if you cruise it set to 30sec,just my .02

RBRotary

the manuel one? cause i can't afford the electronic one lol

Apex944

iTrader: (10)

Search is your friend

Those questions have been answered dozens of times on here and other Rx7 forums as well.

If by boost gauge you mean the factory one then your way off, the factory boost gauge is crap and can't be used for anything other than to watch it bounce...

Get a good boost gauge such as greddy, apex'i, hks, blitz, etc... Autometer has a tendancy to be off by a few PSI so I wouldn't use them but their other gauges seem to be pretty good.

If you already have an aftermarket gauge where did you tie it into?
Only a few places can be used as the boost reference for the aftermarket gauge.

Moving the actuator arm is the mechanical way to increase or decrease boost but it isn't the easiest way, what you need is a boost controller like a greddy profec or something similar if you want an electronic one or the cheap mechanical one's that you adjust the **** on to increase or decrease boost.
The electronic unit is far superior to the mechanical dial cheap unit, as it can be fine tuned to help combat boost spikes and over boosting.

Before I go any further I suggest you research turbochargers, wastegates, boost controllers, boost spikes, boost creep, and search search search this forum as well for that info and anything else you can find about turbo FC's.

Reason I say that is it seems like you don't know much about a turbo FC let alone the basics of how a turbocharger works in general. This knowledge is a must if you plan to tinker with your car yourself, otherwise take it to a rotary tuner.

A turbo rotary is all out with good parts or a dead engine when it comes to modifying them, learned that lesson the hard way and I had everything I needed and thought I would be safe for a little while. Turns out I was wrong and ended up with a $4,000 paper weight ( just parts alone all labor done by me ).
Long story short I had alot of money into aftermarket monitoring systems and things still went wrong even at a safe level of boost which was 10 PSI on a BNR stage 2 turbo.

K-Tune

iTrader: (26)

rtek 1.7 at LEAST, 720cc secondaries, S-AFC, wideband.

THEN you can turn the boost up. until then....no way.

turbo timers are useless on water cooled turbos. just don't run the car hard and turn it off instantly.

RBRotary

well i have an aftermarket prosport boost & oil pressure gauge. and it reads at 4. I just want to atleast put the boost up to nine or something. but i wanna be safe at the same time... but at the same time i'm poor lol so anyway i can SAFETLY & EFFECTIVELY & CHEAP haha

thanks for the help so far guys

Apex944

iTrader: (10)

Not something a fellow Rx-7 owner wanted to hear.... Gotta pay to play with the big boys or keep it at stock 7 PSI boost and be happy with it unless you like to replace apex seals on a weekly basis...

The highest you can go right now is 7 PSI, as it's more airflow than a stock turbo is flowing due to the increased air from the larger compressor wheel.

From the sounds of your posts you have a totally stock FC other than a few bolt on items, you need larger injectors, a tuneable ECU or you can go with an Rtek chip, a way to control fuel pressure, a way to log your air/fuel ratio and exhaust temps, a front mount intercooler is a must with increased boost on a rotary ( my downfall ) as the high intake temps on a rotary are one of it's fastest ways of dieing.

Your fuel system cannot support 9 PSI, the walbro isn't that big of a help without increasing the fuel pressure. If the car is an S4 than you are running even less fuel than you think as they have a fuel pump resistor that cuts fuel flow at low load that will for sure kill your FC if you try anything higher than 7 PSI with your cars current state.

Choose 2:
Fast
Cheap
Reliable ( meaning it will be running next week )

Fast + cheap = dead FC
Cheap and reliable still makes a fun FC but not alot of power
Fast + reliable= alot of time and money which you can't afford to spend which raises the question of why your trying to modify an FC with a low budget... $650 BNR turbo but no money left to support it's increased power....

RBRotary

damn harsh hahaha
so what do you guys think my next step should be?

STR8 FC

a turbo timer isnt really required for a stock turbo cause its oil cooled so theres not gonna be any coaking like a oil cooled turbo even bnr turbos use the stock turbo setup just bigger cold side

RotaryRocket88

iTrader: (7)

Rtek 2.1 or standalone EMS
Wideband
Four 720cc injectors or larger
FMIC or TMIC w/ water injection
Fuel pump re-wire (cheap insurance)

KhanArtisT

iTrader: (2)

LOL, do you know how many people run MBCs? He doesn't need an EBC to run higher boost. Get the supporting fuel mods and run an MBC of your choice, but remember the boost curve will be more unstable compared to an EBC, but nowhere near enough to justify buying one unless you need every little bit of boost response. Spend the $250+ on the supporting mods, lol...

RBRotary

well if anything i'll just want atleast 7 pounds because as i said earlier only 4 is boring.
So as long as i put it up to average specs i'll be happy lol so nothing over 7 could be supported?

i'm sorry if i seem so hardheaded. and thanks for all the input so far

RotaryRocket88

iTrader: (7)

A BNR stage 1 should behave similar to the stock turbo at that boost level (with lower IATs actually), but it's still a guess. You NEED some way to monitor it (wideband or EGT gauge), and you need to ditch the stock injectors.

Apex944

iTrader: (10)

Yes, I do know that ALOT of people use a manual boost controller which is why I posted go big or go home if you want a good strong FC. Sure an MBC will suffice for the time being but before he goes out and turns up the boost the smarter thing to do would be adjust the wastegate to get it up around 5-6 PSI for now and buy an adjustable fuel pressure regulator, some kind of tuneable ECU would be best but a simple Rtek 1.8 chip would be relatively safe, as well as 720cc or 750cc injectors, some sort of wideband a/f datalogging device, and an EGT logging device for anything past 7 PSI of boost.

What I was trying to point out was that going cheap from this point on will make it another one of those Rx-7's you see on craigslist and ebay that were cheaply modded and tinkered with by novice parts changers who had no experiance in the performance world. They took a perfectly good running car, slapped on some bolt on parts that anybody who has used a set of sockets and wrenches can do, turned the boost up and considered it to be a well built car...



I'd also like to apologize to you RBRotary if my word structure came off as offensive, it just get's really old seeing FC's get bolt on parts slapped on them and the owner has no knowledge of how it all works and ends up destroying a nice car.
A quick search of craigslist for a turbocharged FC will show exactly what i'm talking about, especially here in the Sacramento area where i've now seen about 5 helpless FC's get trashed and thrashed and then try to sell them for $2000 and justify the price with all of the bolt on parts they slapped on the car...

Also the fact of living in the world of honda's and mitsubishi's out here in Elk Grove really adds irritation on top of such problems with the car world.

Was just trying to save you from being disappointed in the FC and the car from being possibly parted out or sold off cheaply.

At 7 PSI you should feel a noticeable power increase over the stock turbo and should be fine with factory fuel injection as long as the rest of the car is up to par. Meaning oil changes, spark plugs, timing, plug wires, etc...

Just assuming as I have no idea due to the fact i've never seen your car in person

Better to play it safe then have to spend $2000 or so on a new engine, another $650 on a turbo because the apex seals destroyed the turbine blades and whatever else that got damaged internally.

I pushed mine to far and tried to get away with the factory top mount intercooler so as to save some money on a front mount intercooler setup that I was putting together which is how I ended up with no FC and now owning a '73 240Z...although it was a nice change of car....

RBRotary

hey no worries dude i didn't take it offensively lol thanks anyways though and i appreciate all the advice. So if i wanted to put up the boost though the wastegate spring how could i do that? and how will i know i've reached 7 pounds?

barnett87rx7

iTrader: (1)

not really the stock TMIC is fine it only gets hot if you idle for a while

mikeric

iTrader: (20)

I have had success with Turbo XS two stage boost controller--it lets you run high and low boost with just a flip of a switch and is manual so the reliability is excellent. I used to have a Greddy Profec B, and once it was set, I only ran the high and the low programs and left it alone. So, I had another stupid thing cloging up my cockpit with blinky lights just to run my boost. Turbo XS does the same thing--better.

You must get a boost gauge if you want to start playing with it though and I would highly recommend a wideband AF sensor and gauge (I like my autometer) and a oil and or water temp gauge. You do not know what you are doing to your engine without the proper gauges to tell you.

RBRotary

thanks alot for your input guys appreciate all the good help! but can someone please help me by telling me how i put up the boost through the wastegate? lol

thanks

Turbo II Rotor

iTrader: (2)

A boost controller be it manual or electronic. I would get an aftermarket gauge getting a reference from an appropriate vacuum nipple and wouldn't go even a hair over 7psi until you get a way to control fuel and larger injectors.

texFCturboII

iTrader: (17)

Dude. Search.

Unless you plan on blowing up your motor; you must spend money.

Pure and simple: More Air (upgraded turbo) means you must add more fuel (upgraded injectors) and a means to tune and control said air and fuel (which means a boost controller and fuel computer like a rtek or afc or a completely stand alone aftermarket ECU) and a means to monitor the tune (Wideband 02) and monitor your boost (good boost gauge)

Then when you get used to stock boost levels, you need a Fuel Cut Defender.... if you havent already gone rTek, or stand alne EMS.

Like said above: unless you want to be a rotor hater after owning one for six months and not spending the money needed to keep it working.... correctly.....safely.... and efficiently. Get out of the game.

KhanArtisT

iTrader: (2)

He said he couldn't afford the electronic one and you criticized him of being "unable to play with the big boys" lol...

The point is to spend money on important parts in the right places...and there is no way to "adjust" the wastegate...

mikeric

iTrader: (20)

When I had my BNR stage 4 built, I had Brian put in a 14 lb spring in the wastegate actuator. Changing the spring in the actuator is really the only way to "adjust" it. However, that being said, you need to have the supporting mods to monitor and adjust it. With boost, a wideband 02 sensor and gauge is necessary. Without that, you are just guessing what you need. To tune correctly you need facts. Your boosted rotary will not run long if it is running lean. Unfortunately, a wideband will set you back about $350, but it IS essentual for proper tuning.

Mine saved my engine as it let me know my brand new Walbro was going before it failed (those things are known to fail by the way and if your fuel pump fails under boost...) I now am running a Bosh 944 pump which is much more reliable.

RBRotary

i understand air to fuel. i get all that i've discussed it alot of times. i get it.. more air=more fuel. And thank you to everyone thats helping. i appreciate. i'm just asking for help with my next moves and decisions. and i do have a FCD by the way.

thanks to everyone thats been helping me and dealing with my not to handy rotary skills lol
i want to get into the game of rotarys. no way i'm gonna stop liking them. i just want to get in the habit of knowing. instead of answering questions i'd like to be the ones answering them like you guys. so thanks for helping me move ahead

Apex944

iTrader: (10)

Actually, if brian installed an adjustable wastegate like he normally does then it is adjustable. You shorten the arm to keep the flapper door closed for a longer period of time thus allowing it to build more boost before the wastegate opens. Lengthen it and it allows less boost to build due to the wastegate opening earlier causing it to bleed off boost. I talked to brian through AIM back when I bought my Stage 2 and he told me this information himself which I tried and it worked.


This is where I stop helping as the people posting in this topic are one of my reasons for leaving this forum as well as the Rx7 in general. They would rather talk **** to somebody because they have no life and nothing better to do rather than give them advice on the actual topic.

I don't know what it is about the Rx7 that makes it attract such people....

Yes, I did criticize RBRotary because i've seen too many people cheap out on parts they put on their cars. I personnaly don't like the manual boost controllers which is why I wrote my reply the way I did. He can choose what he want's to choose, I wanted to show him there are better things out there that would be better to use on his car that would allow it to be easier to use and be a better car. Although now i'm apparently a pompass fanboy according to others in this thread, so there's no possible way I can do what I do on a daily basis at my shop...



Good luck RBRotary

mikeric

iTrader: (20)

Everyone calm down. Tone is often misread and I think everyone just wants to help. Yes, there are idiots out there, but I think most people on this site are genuine rotary enthusiasts and love their cars in their own way. Some parts are very pricy but are necessary for a proper tune (stand alone, wideband etc...) However, you can get away with custom and sometimes cheaper stuff if done within reason.

The adjustment that Brian pust on the actuator arm is nice for slight adjustments, but the fact remains that there is a 5 lb spring in there and it will not hold much past 5 lbs.

By the way, Sport Compact Car, back when they were a good magazine and before they went all riced out tested all of the major boost controllers against each other. Of the electronic boost controllers, Greddy's Profec B won hands down. However, Turbo XS worked just as well if not better and had less boost spike (if I remember correctly). I road race, and most people at the track run manual boost controllers (especially the Possche guys) as they are very consistant and will not fail if a wire gets knocked loose or a fuse blows. This saves engine rebuilds in the long run and it is one less thing to troubleshoot on race day (K.I.S.S.). My tuner also recommends the manua controllers as they are easier to set and forget. This was my primary reason for going manual as the cost difference doesn't really matter when you are doing a full race engine build, turbo conversion, and pretty much custom everything into an FB. I went with the dual stage manual because all that is really needed is a low and a high setting. If the electric switch fails, you are not over boosting as it is a spring (much like the spring on the wastegate actuator, just adjustable) that is controlling your boost. I can't think of any reason why somone would say that a manual boost controller is not a good choice, but if I am wrong, please correct me.

If you buy a no name one, then it may break in a month and you are out of your $50. I would recommend the Turbo XS as people have been running those for years with no problems. The single stage is around $100 and the dual stage is under $200--search ebay. Just remember all of the supporting mods mentioned by other posters.