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Old 12-19-03, 02:31 PM
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Poor Mans RX-7...

Ok, I have an 89' TII, completely stock. I want to get some performance gain out of it, but I make $80 a week when I don't work sundays, and $130 a week when I work sundays. So basically I make $80 every other week, and $130 every other week. $30 of it goes to gas, and I usually don't have a lot of expenses to deal with. I only work a few nights a week for only a few hours, because i'm also a student.

I want to go light with the modding, but still get as much as I can out of it (me and everyone else in the world, I know, lol).

I'm a rotary n00b, so I don't know exactly what I should/shouldn't be doing, but i'm trying to read up, but I was hoping some people could give me a few pointers.

I want to do safe mods also, as I surely can't afford a new motor or anything.

So basically, what mods should I get in order if I am under this kind of budget? I want to sort of go in incriments and not save up and blow all my money at once, but I will be getting a few hundred for Christmas and everything to go on top of the job stuff. What mods yield the best performance for the cheapest?

The main reason I posted is to find what kind of exhaust was best for me. Anyone have any suggestions on good exhausts that give lots of power but are decently priced?

Any info would be great, and don't go tell me to search or anything, because I hang out here all the time just reading, so i'm trying to learn all this stuff as fast as I can, but i'm trying to basically get a summed up view of mods I should be getting on a tight budget.

Thanks in advanced.

- Brian
Old 12-19-03, 02:41 PM
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Well, always the spend the money first on restoration parts or little parts that need fixing and general maintenance. Next mods, I would probably go exhaust. But after you get a quality aftermarket boost gauge. With the exhaust, get a Walbro, Bosch or FD fuel pump.

Lots of good exhausts out there. Racing Beat for example for something that looks stock and still very quiet.
Old 12-19-03, 02:54 PM
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How important is the fuel pump with the exhaust?
Old 12-19-03, 02:58 PM
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Depends how much boost you are running...

Not enough fuel and you get an over lean mixture. Lean = kaboom rotary.
Old 12-19-03, 03:03 PM
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Say it was stock everything, but with a basic exhaust? Or even stock boost but very extensive exhaust?
Old 12-19-03, 03:25 PM
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i ALWAYS tell everyone who dosnt have 1000$ for a new motor, and wants to start modding their car. start saveing, get up about 1000$ and put it away for only the motor, dont spend it on parts, then start modding. cause your just about gauronteed your going to need a motor soon
Old 12-19-03, 03:30 PM
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Well if it came down to it, I could afford a new motor, I have like $2k for backup money for now, but its not exactly something i'd like to do.
Old 12-19-03, 03:31 PM
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Get a boost gauge and a FCD. Then a DP and intake. Then the fuel pump. Then the MP/CB. Port your wastegate and get a MBC. S-afc, and dyno tuning.

Custom exhaust will be alot cheaper in the end and produce the same gains if mandrel bent and the same size piping is used. Just be SURE you have the proper fuel delivery and you should be fine up to 12psi with the stock ecu/turbo/ic.
Old 12-19-03, 04:03 PM
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Originally posted by Ryde _Or_Die
Get a boost gauge and a FCD. Then a DP and intake. Then the fuel pump. Then the MP/CB. Port your wastegate and get a MBC. S-afc, and dyno tuning.

Custom exhaust will be alot cheaper in the end and produce the same gains if mandrel bent and the same size piping is used. Just be SURE you have the proper fuel delivery and you should be fine up to 12psi with the stock ecu/turbo/ic.
In what order?

1) Boost Gauge/FCD
2) Exhaust
3) DP/Intake
4) Fuel Pump
5) MP/CB
6) Port Wastegate/MBC
7) S-afc/dyno

Is the stock boost gauge just not as accurate as an aftermarket one or something? How much would a custom exhaust go for?
Old 12-19-03, 04:38 PM
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First mod is a walbro 255 fuel pump from ebay. 100 bucks
Then you can get a FCD and exhaust&DP and get rid of your cat and go with a midpipe. "Best performance gain of the all"

If you don't get the fuel pump and FCD these other things will blow your motor.
Old 12-19-03, 04:38 PM
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Originally posted by Ocelot
In what order?

1) Boost Gauge/FCD
2) Exhaust
3) DP/Intake
4) Fuel Pump
5) MP/CB
6) Port Wastegate/MBC
7) S-afc/dyno

Is the stock boost gauge just not as accurate as an aftermarket one or something? How much would a custom exhaust go for?

Well, go ahead and get a quality boost guage and air/fuel ratio guage.

DP, MP, and CB are all exhaust stuff.

Install a FCD(fuel cut defender) before you do any exhaust or intake stuff.

Then do the DP and intake. +3psi boost

Definately get a fuel pump at this time. I use a Walbro 255. Porting the wastegate now might not be a bad idea, as the next mod will increase boost again.

Now finish off the exhaust with a MP and CB.

DP is a downpipe that goes from the turbo to your main cat. MP is sort of a replacement pipe for your main cat. And CB is a cat back exhaust that goes from where your cat used to be all the way back.

And an S-AFC is the next step. All this does is modify the signal coming from you AFM to your ECU. This way you can richen or lean the mixture out as needed. Have a knowledeable tuner do it for you if you don't have a clue.
Old 12-19-03, 04:40 PM
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Oh, the stock boost guage for one, doesn't read in PSI. And it's not nearlly as responsive as an aftermarket guage. I'm at 2psi when my stock guage says 0.
Old 12-19-03, 04:46 PM
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If you have to be totally safe, I'd do these things first:

1. FCD
2. walbro pump (ebay)
3. good boost gauge (stock one is pretty useless)
4. s-afc
5. Port the wastegate/MBC
6. intake/TID mod
7. full exhaust (what depends on if you have emissions)
8. dyno tune prior to getting on it


You will be totally safe with that setup, but it won't be the fastest until you get on the dyno.

Normal modding goes more like this:

1. intake/boost gauge
2. fcd/fuel pump
3. DP/MP (I went with the thunderfabrications $200)
4. port wastegate/MBC
5. catback and/or TID mod
6. S-AFC and dyno tuned
7. larger injectors/hybrid turbo/tuned
8. fmic/tuned
Old 12-19-03, 05:03 PM
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get a job bartending. That's the first mod you should do. You can make a grand a week cash easy working 3-4 nights a week. Then you can buy whatever the heck you want!
Old 12-19-03, 05:13 PM
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I read somewhere about a DIY FCD. Is there an easy way to do it? Well, doesn't even have to be easy, but as long as it has clear directions and works as effective as any other product, because I know my way with electronics and building boards and such. I would really rather do it myself and save the money if it will work just the same as a purchased one. Anyone know about this?

Also, could you explain the port wastegate/MBC? Sorry about all the questions, I hope I don't sound like too much of a n00b, but i'm trying to get a lot in at once.
Old 12-19-03, 05:14 PM
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Originally posted by kmags
get a job bartending. That's the first mod you should do. You can make a grand a week cash easy working 3-4 nights a week. Then you can buy whatever the heck you want!
that would be nice, but first i need to know how to make drinks, lol

During the summer is when I expect some real money as i'll be working most of the time during the day, i'll have a lot more hours, and a better job by then, and a friend of mine and I are going to start building/repairing comps and setting up home networks around town for some extra cash.
Old 12-19-03, 05:47 PM
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Search for porting the wastegate threads. As for a MBC, that means manual boost controller. The reason I suggest a manual one is they are alot cheaper and you can make one yourself from parts at home depot. Also, you will need one once you port the wastegate to bring your boost level back up to where it was or where ever you want.
Old 12-19-03, 05:55 PM
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if your only making the much save your money and wait for a better job oportunity. Its not worth going backrupt for a car. Even an Rx7

justin
Old 12-19-03, 05:58 PM
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I'm only a senior in high school about to go to college. This money is pretty much my spending money for myself because my parents kindly offered to pay for my insurance (minus whatever I do that makes the rates go up [accident, ticket]. I just chose to spend the money on my car and learn a few things rather than other things. I won't be going bankrupt anytime soon (until I move out on my own and buy myself an FD, )
Old 12-19-03, 08:11 PM
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Hmm....probably should have thought about this before, but I don't really want to pay to install any of this, so how hard do you think it would be? Are there usually good enough directions included with most stuff to do it myself. I would say i'm an above average builder of all sorts of things, but I don't have too much car experience under my belt. I've worked on air conditioning units, watercooling, computers, and just random crap that I like to take apart, so would that do me well enough, or should I get someone who knows their rotaries to do the installs?

I mainly need to know how easy it is to install the fuel pump, fcd, intake and gauges, because the exhaust stuff i'll probably get later and done custom. I know my wiring well, so I guess its more a matter of knowing where things are, and what is safe to move where. I can always ask for help here, but just wanted to get a general idea. Thanks again for all the help guys.
Old 12-19-03, 08:16 PM
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Everything listed so far is easy to install yourself. Don't worry so much, ask questions and you'll be fine.
Old 12-19-03, 08:43 PM
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Ok cool, i'm going to buy an A'PEXi Power Intake as my first mod, although i'll probably wait until I get the fcd and fuel pump before I put it in, just figured i'd get it while it was cheap. I buying it new used (never opened, but purchased and owned by someone) from someone on the forums that lives right by me so i'll just keep hold on that until I get my FCD.

Just wanted to make sure that this was a good choice for an intake before I try and go through with it.
Old 12-19-03, 09:14 PM
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Originally posted by Ocelot
I read somewhere about a DIY FCD. Is there an easy way to do it? Well, doesn't even have to be easy, but as long as it has clear directions and works as effective as any other product, because I know my way with electronics and building boards and such. I would really rather do it myself and save the money if it will work just the same as a purchased one. Anyone know about this?

Also, could you explain the port wastegate/MBC? Sorry about all the questions, I hope I don't sound like too much of a n00b, but i'm trying to get a lot in at once.
http://www.fc3s.org/how_tos/electrical/fcd.html

If you're handy w/electrical stuff then this would be a breeze. I'm so-so with the iron, but mine worked like a champ right outta the gate.

Getting everything in proper nick maintenance wise should be first up before any modding.

Wideband a/f setup, good boost gauge, port the wastegate, MBC, ramp up the fuel system, then open up the intake and exhaust.

Terribly conservative, yes, but your wankle will thank you in the long-run.

Cheers
Old 12-19-03, 09:49 PM
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Can someone explain porting the wastegate to me? I did a search for it, but it came up in too many random spots to find a guide or what the hell it meant.
Old 12-19-03, 10:08 PM
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One other thing, I read this on the DIY FCD tutorial. Would it be anything I would need to be worried about only with a basic intake exhaust setup and they are directing that towards very modded cars?

There are a couple of immediate consequences to this fooling around. As the boost rises, the ECU must increase the amount of fuel being delivered to the engine in order to maintain safe and efficient operation. As the FCD starts lying to the ECU, the ECU will begin to under-compensate for the rise in pressure leading to a gradual leaning of the air-fuel mixture. The amount of error increases as the boost rises. For relatively small errors, the only penalty is efficiency. As the error gets larger, however, detonation becomes likely, exacerbated by the high boost pressures and accompanying high intake charge temperatures. Detonation under these conditions will quickly kill an engine. So, before we go any further, be forewarned that using an FCD and increasing boost pressure without also compensating for the ECU error with fuel enrichment (and preferably more efficient intercooling) can cause serious damage to your engine!


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