I've got a s4 TII that I just had gotten rebuilt last fall with a large street port and 3mm conversion and I just purchased an s5 bnr stage 4 that should be on its way. Anyone got any advice on this build as far as intercoolers, what to look for? and also what are people using for UIM's? Those all FD with some kind of spacer? I am setting this car up for drift, is v-mount recommended? I am looking for as much horsepower as the turbo can put out without cracking the motor... I just don't wanna over do anything and buy stuff I dont really need, I like to stay practical. Thanks for the help.

p.s. I tried searching and reading as much as I could, but it just wasn't specific enough to put my dollar on it, I hate bothering people.

 

I am in the same dilemma, and thought about doing front mount but since my car is used a lot for auto-x I dont want my coolant and oil temps to go up, so I thought v-mount, then I wasnt sure if all the work was enough considering I dont want to make crazy hp (350 or so), so now I am looking for an upgraded top mount and prob doing water injection.
Look up AI, its interesting and the best intercooler around, wont add lag and will clean and protect your engine.

 

The perfect ic.
https://www.rx7club.com/west-sale-wanted-classifieds-195/rare-smog-legal-hks-fmic-953585/

 

What's AI? alcohol injection? or a brand name? I can't find it.

 

Why did you choose a bnr s5 turbo when you have an s4?! I believe you will get more area out of porting the single wastegate on the s4 than the two on the s5.

Anyways, I would highly not recommend the rotary works vmount kit, and stay away from a v mount completely if you are on a budget. I have 3000$ (parts and labor) into my vmount setup. It's nice, but not cheap to do the right way. There is just way too much involved if it's not a project car.

I would try a greddy or a freddy fmic. With a freddy at around 400$, try it. That's chump change. Have an experienced shop fix problematic areas (like no bov flange).

 

If you are planning to do autocross, then a front mount is not for you. Water injection and a top mount will work just fine. If you want to spend the money then a v-mount setup is ideal, but costly. Unless you are good at fabrication.

 

Isnt' that just for the FMIC? You'll still need to incure the cost of the custom piping and other odd installation costs you don't do yourself. Perhaps another $400.

 

What is your budget?

It stands for "Auxiliary Injection". On this forum the term is often used as a misnomer for Anti-Detonant Injection (ADI) systems. Outside of internet forums, the AI term would also include gasoline delivery devices such as "additional injector controllers" and "auxiliary injector drivers".

 

a front mount will be fine for drifting if you have some type of ducting or run without a bumper. im cheap so an ebay front mount for me will do for the mean time, since im planning to only run the stock turbo and ecu with 550/750 for my drift setup. keep it simple and reliable if you wanna drift the **** out of it.

ebay front mount. 2in core should be more than enough any bigger is just retarded on a stock turbo

 

S5 turbo has a divided exhaust manifold and dual port wastgate. No twin scroll either. The wastegate is huge compared to the S4. I run a S5 BNR stage 4 on my S4.

I have the godspeed/greddy knock off FMIC. Its great. I got it for $299 to my door. Fit well.

http://cgi.ebay.com/ebaymotors/GODSP...Q5fAccessories

 

Yes. Keep in mind a turbo rotary likes to stay cool. A front mount can be made to work good. A VMIC will work better.


IDK how people think a vmic is always expensive, from a budget standpoint you can cut a hole in the hood and put on aftermarket vents(or just run no hood if its a drift car). Find a good used intercooler core for $100 and fab up the piping your self, barely would cost anything.

Or go all out if you have the money and set it up legitimately.


As far as the FD upper intake, theres a good thread on that, just run a search. imo though, just keep the stock mani if your not looking for 500+ hp.

 

@iani1.1 looks good! However, drifting and no bumper I would think wouldn't go together well. Your car might end up looking like this guys car:



You could retain the bumper and cut a hole in the center of it for more flow if needed. My last car I had a metal bumper underneath the cover and cut it so I had two halves. Plans were for an intercooler eventually. I don't know if I would do that with a fiberglass/plastic one.

 

thanks, true but i am gonna run a gp or msports front bumper with a duct. should help direct airflow while moving sideways. i have an intercooler sprayer that i rigged up from and sti thatll be useful on hot days and ill also be leaning the fmic slanted forward. im going for reliability here so we'll see what happens when i get back on the track.

also you can go with a vmount but its gets pretty expensive even with free parts. welding is a must as well. then you gotta get a dmax hood or something of the like to have better efficiency.

 

I dunno man. It looks like their port job on the S4 has more surface area than the port job on the S5.

 

I didn't think they were allowing water/alcohol injection in autocross...you may want to check the rule book on that. Last I knew, they weren't allowing it.

The cost of a v-mount is greatly impacted by your personal skill set and tool availability...the more you can fab yourself the cheaper it will be.

 

I was comparing stock vs stock. I think bnr gets the S4 wg to 38mm, that's pretty big. Does bnr list what he gets the S5 out to?

 

I think your forgetting a few things.

Here's my list of what I think would need to be done to successfully complete a vmount setup;

Radiator (it's an upgrade, and getting an aluminum one will allow you to weld nozzles differently and duct work to it)
Intercooler
Relocate oil cooler or get side mounts (support bar might be in the way, and if you leave it in the stock location would defeat the purpose of a vmount unless you had crazy duct work)
Brackets for everything
Duct work (so air is channeled to each cooler)
Couplers and clamps
Plumbing and tubing
Throttle body tube
Cut hole in hood or get hood with vents
Electric fan and shroud
Bov

Like I said before- a lot is involved.

Here's my modified rw kit so far. Ordered half the items left needed to complete it yesterday.

 

Nah. Just going by photo. BNR says 34-35mm on s4 from stock 11mm. Maybe some one with cad skills can tell us with these photos. So waste gate aside, would the twin scroll design boost performance enough (with a larger cold side compressor BNR) to swap manifolds?

 

You missed the last part of what I said about the legitimate way of doing it

Personally I have over $1k invested in the start of a proper vmic setup, and I'm not even close to having everything I need.



The point I was making is, on a budget standpoint, you can mount an intercooler between the stock rad and engine, or if its a bigger core, fab up some brackets to angle the radiator more. It can be done cheaply.

 

I didn't exactly choose an s5, my turbo was shot and after I got a rebuild I found a sweet deal for that stage 4 s5, so I took it.

 

I think autocross would also be fun, are you talking a stock TMIC? or some fatter aftermarket one? and then just water/alchohal injection?

 

I have a fairly large budget (about 1800/ months just to play with) but I wanna get the car back together and broken in as fast as I can and I still need other parts.

 

Can any intercooler core be fabbed up to fit as a VMIC? My neighbor out here in the sticks of NY happens to build funny cars and can do any fabrication imagineable.. he just has a long waiting list of race cars and said itd be till august, unless I have something that would only take like 8 hours max

 

OK, I think you have the funds and skill available for a pretty decent setup. See this horizontal setup as an example:
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/pics-blue-tiis-awesome-engine-setup-hfmic-145822/
https://www.rx7club.com/showpost.php...9&postcount=21

Note these things:

- The intercooler has the inlet/outlet piping coming straight out of the end tanks. This eliminates two 90deg bends that you see on most intercoolers. Given that each 90deg bend costs about 0.2psi boost, that comes out to about 0.4psi total. This will result in a faster boost rise, and in most cases also a higher max horsepower. If you can only find an intercooler like tuscanidream's, then simply use a band saw to cut off the end tanks, and then fabricate new tanks in the proper configuration. If you are shopping for intercoolers that advertise a cfm rating, then something around 700cfm or higher should be about right for the BNR Stage 4.

- For a road car you want each heat exchanger (radiator, intercooler, oil cooler) inlet to be about 1/4 the area of the core. I don't drift, but I would guess that a larger (maybe 1/3?) inlet would be better for operation at lower vehicle speeds. Proper ducting is your friend. If there is room, then also place ducting on the heat exchanger outlets. An optimal outlet would be at least as long as the heat exchanger core is tall, and the outlet should have an area about 15-30% larger than the inlet.

- You probably want to install some good cooling fans. Spal makes excellent fans, although they are rather expensive. Puller fans work much better than pusher fans, and straight-bladed fans tend to be more efficient but also more noisy than curved-blade fans. The 2Gen RX-7 is well-known for its weak alternator, so a large fan load may require an upgraded alternator. Also, a running fan will start to restrict airflow through the heat exchanger at vehicle speeds over 30-40mph, so it is a good idea to install a thermostat controller or other type of controller that will turn the fan on and off as needed. A cheap manual switch usually ends up in a blown engine that one time the driver forgets to turn it on.

 

That horizontal intercooler looks amazing. I would like to see his results with a vented hood as well.
When auto-xing a FMIC will inhibit the function of the radiator and oil cooler resulting in higher engine temps and possible overheating. I would think that in drifting the same would be an issue, but removing the bumper really opens up some ventilation.