drift13b88

iTrader: (1)

Hi, hows it going i own an 86 Mazda Rx-7 N/A s4, im currently building it up parts i have so far on car are

fluidyne s5 radiator, centerforce dual friction pressure plate, exeddy stage 2 clutch disc, Rc racing 550cc primary injectors 650cc secondarys, hks air intake kit, 2 to 2 custom header, to h-pipe(true cross over pipe to 300zx dual n1 exhaust, ngk platinum spark plugs, 10mm silicone wireset, no emission systems, block off plates everywhere, high flow fuel filter, pulsation damper eliminator bolt, s5 4 piston calipers upfront, turbo 2 seats, 14 inch 3 piece Epsilon rims, falken ziex ze512 wheels, wheel spacers, turbo 2 hood, royal purple gear oil in the tranny.

i feel like im dumping to much fuel running rich i wanna get a new pump from rx7.com
and upgrade the ignition system what msd parts do you guys recommend? also would switching over to synthetic oil be a good idea if so what is good motor oil for the rx7

RotaryRocket88

iTrader: (7)

550 and 650cc injectors are WAY too much if you're still using the stock ECU. The ECU will still run them as if they are stock 460cc, which means lots of extra fuel throughout the map. Stock injectors and the stock fuel pump are more than enough for basically anything you can do short of forced induction. The only real power adders you listed are the header/exhaust and maybe the intake, if done right (box or ambient air ducting), so you're not going to be seeing dramatic changes in fuel need.

The stock ignition is very good on FCs, and a popular upgrade for some cars even. Quality synthetics are fine, but will cost more. Oil is covered in the 2nd gen FAQ stickied at the top of the section.

Aaron Cake

iTrader: (1)

I'd recommend just sticking with a stock replacement clutch, unless you are heavily tracking the car. You'll never make more then 200HP, which the stock clutch will handle fine and not task you with the hassle of driving a stiff aftermarket clutch.

Whoa! That is WAY too much fuel. Stick with the stock 460CC injectors and have them serviced by an injection shop. Then use a piggyback to actually LEAN OUT the fuel curve of the car. Mazda runs the engine too rich, so you will see significant gains by leaning it out.

A h-pipe will just cause interference in the exhaust pulses if not tuned properly. Best to either merge them after the header, or run true duals out to the back of the car. Oh, and be prepared for noise.

Evil Aviator

I am not familiar with the size of the 300zx dual N1 exhaust, but it should work well for your car as long as it is sized for NA engines rather than turbo engines. H-pipes don't work on rotary engines, so you may was well replace that portion of the exhaust system while you are fixing up your car. See this link for rotary engine exhaust performance tips:
http://racingbeat.com/FRrotary.htm

Synthetic engine oil is a waste of money unless you are racing your car on a track, or you drive in extreme hot or cold conditions (in which case you should probably trade your RX-7 for a Range Rover). However, synthetic oil works great in the transmission, and it also works pretty well in the differential. The most popular rotary engine oil for street cars is non-synthetic Castrol GTX. As for race cars, most of them use fully-synthetic oil from Idemitsu, although Red Line, Royal Purple, Motul, Amsoil, and Total/Elf synthetics are also used.

I recommend installing an Aeromotive or SX fuel pressure regulator. They have a built-in pulsation damper to compensate for your deleted damper, and they will help keep your fuel pressure level if you want to fine-tune the engine with the aftermarket fuel computer that you will need for those fuel injectors.

Also, make sure you replace the HKS air filter element every year or every 10,000 miles. When they get old and crusty the foam tends to break apart and the pieces get sucked into the engine. Note that these filter elements are disposable, and are NOT intended to be washed and reused!

canonize-ryda

would u guys honestly think that a FPR from ebay would contain a internal damper. it was about 30 bucks and its adjustable. ive never got around to hooking it up either. can i use the stock fpr and add the aftermarket one inline somewhere before the stock fpr?

drift13b88

iTrader: (1)

thanks guys for the help so far, if i retained those injectors, and run a fpr cant i keep the flow in check also if im planning on a port job would it work, if so what parts would work for me as far as fuel mang. and ignition upgrade and i aint rocafella so be nice on my pockets but im no cheap sally either thanks guys

Evil Aviator

I would assume that it does not have the damper function, but you would need to contact the vendor for that information. Anyway, the main point of having a nice aftermarket FPR is to maintain a rock-solid fuel flow so that you can tune the engine better, and I think a cheapie FPR would probably work worse than the stock item. I would also worry about a cheapie FPR failing and causing an engine fire.

No

The FPR can only adjust the global fuel flow rate. While this helps tuning by setting a good base, an aftermarket fuel computer is required to tune the engine at different rpms and load settings. Attempting to tune globally can result in some areas being too rich and others being too lean, which can destroy your engine.

I think the cheapest route to control both the fuel and ignition would be an Rtek Stage 2, Microtech LT8, or Haltech Sprint RE.
https://www.rx7club.com/rtek-forum-168/
https://www.rx7club.com/microtech-111/
https://www.rx7club.com/haltech-forum-62/

drift13b88

iTrader: (1)

im gunna look more into what u guys said thanks

canonize-ryda

yea not saying it hasnt been said but the stock components usually are more than ok for modding on top of. un less u do a turbo swap most things are better left.

Aaron Cake

iTrader: (1)

There is no advantage to keeping those injectors. That's enough injector for a turbo 13B making about 300HP, and is way, way, way too much fuel for your NA 13B that will struggle to break 200HP. Stick with the stock injectors, there is no reason to upgrade them at all. Stick with a stock fuel pump. Use a piggyback to pull some fuel from the curve.

Even if you port, the stock injectors are fine. Only when you get into radical porting like bridgeporting do the stock injectors start to become small on an NA. Of course at that point you'll be running a standalone and can drive the injectors harder then the stock ECU, so you can pull higher duty cycles out of them and extend their capacity quite a bit.

You don't need any ignition management on an NA. For fuel, you can get away with an inexpensive piggyback like the S-AFC.

Does the engine run well as it is? Then don't pull it apart and port it.

canonize-ryda

well said about pulling it apart and porting it.

drift13b88

iTrader: (1)

does the s5 n/a run 550's why so, what do u guys think of removing the 5th and 6th ports from the intake manifold, and what about the o.m.p

drift13b88

iTrader: (1)

Aeromotive or SX fuel pressure regulator. They have a built-in pulsation damper to compensate for your deleted damper

im interested in the built in damper witch one is it part number wise or model

Evil Aviator

S5 NA Injectors are 458cc@2.5bar. If you are not familiar with electronic fuel injection, the control unit meters fuel by time (milliseconds) rather than mass or volume. During engine acceleration, the stock control unit does not have any input for fuel injector size or fuel pressure, so if you change one of these factors then the control unit will not know it, and it will continue to attempt to run the engine assuming the stock size injectors and fuel pressure parameters. Given the same injection time, the engine will run richer (bogging, hesitation and bucking) with larger injectors or higher fuel pressure, and it will run leaner (hotter, knocking and bucking) with smaller injectors or lower fuel pressure. Therefore, if you install larger 550cc injectors in your NA engine, it will run like dog crap on the stock control unit.

Removing the 5th and 6th ports is a great way to lower the torque and hp of your engine if you think the car is currently too fast.

Removing the OMP is a personal preference. I like to keep the OMP on a street car because filling the gas tank with oil on every gas fill-up is a pain in the rear, premixing uses more oil (more money and worse for the environment), and if sombody borrows your car they will most likely screw it up. If you are building a track-only race car, then premix and a dry oil sump are definitely the way to go.

Keep in mind that these universal fuel pressure regulators are not direct fit, and will require appropriate AN or pipe fittings, possibly new fuel lines, a fuel pressure gauge, and the skill to install and set up the equipment. This is not a good modification for noobs to attempt on their own, so I recommend that you have a skilled mechanic perform the work. What you need is an EFI bypass type regulator that can be set to 34.1-39.8psi in order to work with your stock control unit. Regulators with -6 or 3/8" inlets/outlets will work fine up to 500hp. The exact sizing of inlets and outlets depends on what your mechanic thinks will work well with the availability and price of fittings and hoses, so you should discuss this with your local performance shop before you buy anything. Plan on spending about $500-800 for this work. If you are just going to use the stock engine control unit, it would be cheaper and easier to keep the stock regulator and either reinstall an OEM damper or keep the engine as-is and accept the minor problems associated with eliminating the damper.
http://www.sx-performance.com/Regulators.htm
http://aeromotiveinc.com/products-pa...fi-regulators/

drift13b88

iTrader: (1)

im gunna keep the omp installed, run stock injectors, deff gunna scrap the hks air filter, probly get an m7 japan one, stock fpr is fine and its brand new, ive heard removing the 5th and 6th port make power i gotta look more into it, i need a dual alternator pulley, i now have two rc racing 650cc injectors if anyones interested installed but never used never reved past 3800 and car isnt on the road pm me i have a complete parts car blown water jacket seals but a complete car if anyones looking for parts 86 s4 n/a mt, looking to sell the shell cheap hard top no sunroof pm me, and the one last question i have is how can i make more power serious answers please no i cant buy turbo motor so rule that out of your answer thanks guys i look up to some of you

Aaron Cake

iTrader: (1)

Removing the aux ports only results in a reduction of low end torque, and no power increase up top. It will make the car slower.

If you want to make more power, get a header and a nice exhaust system. Pop on a cone filter with a proper cold air box. And then tune the car with either a piggyback (acceptable) or full standalone (much better). You can probably get close to 200HP out of it.

drift13b88

iTrader: (1)

is there anywere to get an intake box or should i just make one, any advice on making one

beauistheman

big injectors, you need an aftermarket EMS to control what you want properly.

drift13b88

iTrader: (1)

any info on an intake box could the racing beat rx8 work/fit

elmayimbe4eva27

iTrader: (2)

Here you go bud:
http://www.mariahmotorsports.com/eng...iah_airbox.htm

Aaron Cake

iTrader: (1)

Just search the 2nd gen forum for:

"cold air box"
"prelude intake"
"cold air intake"