i have an 88 na fc s4,i believe thats right.i am currently entertaining the idea of adding a turbo to the engine or a supercharger.wondering if i could get some input on pros and cons of each application,maybe suggested manufacturers parts etc.thanx for your help

 

My suggestion would be to look into doing a turbo2 swap. At least then you can drive your car as it is right now while you tinker with your engine on a stand.

What's your budget and power goal?

 

Look up arroncake(I think that's his screen name) but he has a how to do it your self turbo NA. Also it depends what you want if you want easy bolt in power do a tII swap with bolt on and oem ecu. Turboing NA engines take a little bit more work but you can make some great power out of them too.

 

"Look up arroncake(I think that's his screen name)"...NO,that is not his name!
it is AARON CAKE.
Aaron's Homepage That will give you your info.

 

^ Aaron Cake's home page is a GREAT source of information.

I'll post a few other informative links...

RX7 Club: 2nd Generation FAQ's
Rotary Resurrection: Technical Menu
Foxed: FREE Factory Service Manuals
FC3S Pro v2.0

And if you decide to go through with a TII swap... Keep the name Japan2LA in mind. He's a reputable JDM engine importer on this forum.


Feel free to check out Aaron Cake's 13B rebuild video on You Tube! -> http://m.youtube.com/?reload=9&rdm=m...?v=ijJeUk_GqiI

 

Or just buy a TII and be done with it

 

That^

Keep in mind, the whole drivetrane is like a chain, only as good as it's weakest link. For example, an NA tranny was designed to handle NA type power. Actually, barely able to handle NA power.

If you want to improve your NA, go the NA proven NA rounte. RB Downpipe & presilencer, AFC, drop in K&N, lightened flywheel. Done.

 

HOZZMANRX7, I've heard about the NA tranny being weak. Is it just the input shaft that's the weak part or are the gears and such weak as well? I've noticed the MazdaTrix miata shaft mod plenty of times, but no mention of the rest of the trans. I'm wanting to keep my ratios and probably drop a 3.90 rear in eventually.

 

+1


a DIY turbo isn't an easy task even for the knowledgable mechanics.

if you want more power and reliability your best bet is to sell the N/A and buy a stock TII, if you can find one.

the n/a drivetrain is weak, even for the non turbo cars. there is really no way to upgrade it aside from swapping out the whole drivetrain for turbo components which is a huge step up.

 

Damn, I wanted to keep my ratios. Greedy me haha. There goes my plans for a very slight to mild sp and 3.90 rear.

 

NA syncro's if nothing else are barely in spec to deal with NA power.


Very slight to mid HP increase and 3.9 rear, see my NA power upgrade comment. With the 3.9, I promise you won't be disappointed. But for the same reasons, you might want to swap in a TII tranny at the least. Bigger clutch disk to hold on to that power increase, etc.

 

I guess with the 3.9 rear and a TII trans rpms shouldn't change too much.

Back on topic, I currently have done the RB downpipe, pre, and catback and it did make quite a bit of difference and I love the resonance at ~3k it really starts sounding meaner. Didn't do a K&N, had some high density foam that I cut to shape and works extremely well, plus it's washable and won't wear out like all the other K&N's, after tons of washes, I've ran in the past. Can't comment on AFC or flywheel... yet. Plan on Squirting here soon and a flywheel just doesn't seem streetable enough for me, though I might consider a light steel and a six puck sprung hub but definitely not an aluminum.

 

I'm in your camp on the flywheel. Went with aluminum route first, hated it what with all the slip clutching you have to do in congested driving situations. Switched to Lightened steel and have never looked back.

You won't be generating enough horsepower that you'll need a 6 puck, and you will hate the 6 puck even more than an aluminum flywheel for Daily Driving.

As to ratios:

Application 1st 2nd 3rd 4th 5th
87-88 RX7 Non-Turbo 3.475 2.002 1.366 1.00 .697
86-88 RX7 Turbo 3.483 2.015 1.391 1.00 .762

 

Yea, I've done a lot of research on ratios. TII trans alone would bump up cruising rpm and 3.90 rear alone would drop it. If I'm doing my math right, it should put me about 85 rpm higher at 55mph.

If I'm going the TII trans route I am going to be attempting to try for big streetable NA power, key word try since I know how most NA big power threads/dreams go.

Edit: Forgot to add, how much slip, if any, is needed for a light steel? I've been needing to slip less and less since I'm getting the stupid first gear shudder, annoying as hell probably need to replace engine, trans, and diff mounts. Don't want the torque brace band-aid, it's a damn NA I should be making less than stock torque with my RB exhaust.

 

Oh, forgot to mention, my math was on a stock 205/60/15 at 24.7" tall.

 

^ I was about to say that gap could be narrowed simply by running a slightly taller tire.

I've got lightened steel on both TurboVerts and my NA GSLSE. No shudder, minimal slip clutching needed from a stop. Shuddering, sounds like you have glazing issues on your flywheel or pressure plate.

 

Well, it's a new clutch with only about 3000 miles on it and the flywheel was resurfaced at the time.

 

weird

 

Yep, lol, but not worried. Everything else is pretty much fine, need to redo front wheel bearings but that's off topic here, so I shall end my thread jack.

 

FCs are just slow. by the time you dumped the money into a TII, making it fast, you could have bought an FD. upgrade the suspension, brakes, tires, clutch. then do the little stuff like full exhaust with silencing and a drop in K&N. then you have a quick canyon cruiser that will make you happy and not end up in a flipped at the bottom.

 

Some of us like our FC's and would dump endless amounts of money into them before ever considering anything else even if it may be cheaper.

 

I think I'm still on top. If I took all the money I ever spent on my FC (upgrades and purchase price, routine maintenance not included) and bought an FD with it, I'd have one gimpy, torn up, near end of life, generally shitty FD. This is not to mention that I have a convertible, which you can't get in an FD. Stock FCs are slow. So are stock FDs. You just have to know how to appropriately utilize your money. My convertible is now faster than a stock FD hands down, and it's much more fun to drop the top and haul *** in style. The only reason I want an FD is for their beautiful body lines. The finicky electronics and inexplicable high price keeps me from actually getting one. Don't get me wrong, the FC has its fair share of electronic problems, but the FD is just... wow.

OP, here's how you add horsepower.

1) Look for a rich fool who is LS1 swapping his TII.
2) Convince him his old rotary is worthless, and take the whole drivetrain (he won't need any of it except the rear end) for a ridiculous low price. Get everything.
3) Sit down and read threads about turbo swaps for no less than 30 days. Get a notepad and write down notes about stuff. Collect everything you read about that you're going to need.
4) Start the swap. If you run into a problem you didn't read about, search first. If you still can't find the answer, you may ask. I'll bet that with the power of google and the search button on this forum, you can find an answer to any question you have.

 

^Sound advice in every respect.

 

**** I had the nicest vert. needed a new top and driver seat and it would have been a 9/10. Every bolt on, new Pineapple rebuild. sold for $3k almost a year ago. so yeah I guess you could put the other 7K into it and had 400 hp and feared by most, still you got to admit a FD handles better with stock suspension that an FC with struts/springs or cheap coilovers.

 

I'm sure that stock vs. stock, the newer car wins. I would sure hope that Mazda got some good research and development out of the FC for designing the FD's suspension.

It almost sounded like that thread over in the non-technical section about the FC "meeting its match" when compared to that new RWD Subaru. I'm not going to say that I can build a better car than the BRZ/FRS, but I will say that I'd rather buy a $2k car, then put money in it when I'm good and ready to, rather than making $500/mo payments. Getting an FD is along those same lines. Paying $10-17k for a car that hasn't been made since '95 would give me $200 to $300 per month payments for around 5 years. People like me would rather spend the smaller sum up front for a good running car, then trickle in what I want, when I want. If I have to fork over some extra money because my kids need (insert anything here... seriously), then that new (insert upgrade here) can wait until next month, and I'm cool with that.