Critique my buildup!
 

I'm about to dive into my project, but before I do, I'd like a little bit of advice and/or pointers. Here's what I'm looking at:

1990 RX-7 GX (Canadian model, sort of like a GTU).

First and foremost, I'm doing a Renesis with the 6 speed. I know all of the obstacles, but I am pretty sure I can handle them. My dad is a great welder / fabricator, and very wise in electronics. I have never confirmed a Renesis in an FC, only heard rumors. I'm not looking for big power; I'll explain more later.

My goal is 350whp on nitrous, 250whp without, and 10K rpm readily available. It's an optimistic goal, but I'm convinced it can be done, with all the bolt-ons. What porting would be best suited to this goal? (keep in mind this will still be a STREET car that will see track duty every now and then). Power/engine modification list is as follows: RB catback, RB presilencer, KnightSport header, pullies, P/S delete, maybe A/C delete, lighter flywheel, Tweakit ITB's (I'll 'glass a duct from the hood), a fuel return line with adjustible FPR, 100-125hp nitrous wet shot (125hp acceptable with return line?), Walbro 255lph pump and Megasquirt. Will a ported Renesis stand up to 10K rpm and nitrous? If so, for how long?

Next up, suspension and etc.
Wheels will be bronze 5Zigen FN01R's, tires will be Falken Azenis RT-615s.
Front: 17x8 + 25 225/45R17
Rear: 17x10 + 35 255/40R17
Mazdatrix front STB
Cusco "V-brace" (rear STB)
Cusco arm brace
Corksport or RB DTSS eliminators
RB sway bars & sway bar bushings
Prothane master bushing kit
AutoExe brace kit
Rollbar of sorts (probably custom job)
Ohlins dampers already sitting in my closet

Hood will be a turbo-style carbon hood, probably painted body color (Blaze Red). Some sort of front lip/diffuser, turbo skirts, RE-Amemiya Wangan wing, Endless or AP Racing front BBK, stainless lines and all of the other brake stuff.

Sounds like a lot of money into a N/A FC, I know. Everyday as I'm scanning this site, it's just turbo after turbo, and the N/A gets little respect. I'm looking for reliable power, and great response. I'm a fan of turbos, but this time it just doesn't feel right. The car will be tracked on circuits, and probably autocross too (I went pilon-dodging once last month. I'm hooked). I obviously want a very unique car, one that can make FC owners proud to call one of their own. I'm 19 (20 in 2 weeks), am on very good terms with my parents (this means no rent :rlaugh: ), I have $150 / month in bills, a job as a tech at a Nissan dealership (done my time in college already), a side job delivering pizza (pays all my gas, meals, bills, etc.). Overall, I have no life. :)

I bought this car last year as a writeoff. It was in great shape, but it kissed a curb. I fixed it and I've been driving it for the past year without issues; my dad and I resprayed it in Blaze Red earlier this spring. I tried selling it earlier this year, but lowballer after lowballer has convinced me that not only should I keep my FC, but show them what they are missing. Do you know what it feels like to have someone in another province, who has never seen your car in person tell you that your beautiful, well-kept, rust free and freshly repainted car is worth $2000? Keep in mind this is Canada. A car in this shape is very rare, and bagged S5's with blown motors typically fetch around $1500.

http://img167.imageshack.us/img167/4...ters106ge0.jpg
http://img167.imageshack.us/img167/2...ters092eg9.jpg
http://img149.imageshack.us/img149/2...ters091rg9.jpg
http://img241.imageshack.us/img241/7530/rx7007ep5.jpg
http://img156.imageshack.us/img156/2719/rx7005vf0.jpg

I'm all ears here-on out.

If your numbers are accurate as quote below, you're asking that motor to produce *TWICE* as much power as it did STOCK.
Not looking for "big power"???


Not recommended...
The RX-8 motor is high strung as it is.
Mazda did not design it to handle much more power than stock levels.
You're going with a big hit of nitrous.
I bet money the motor is going to eat itself unless we're talking about SERIOUS money thrown at it.

My recommendation if you're going to insist on NOS...
Stick with the original FC 13B.
The PP exhaust port allows for better breathing.
You're going to throw away the stock intake system (which is one of the biggest advantage of the RX-8 engine in the first place), so the short blocks isn't going to be that much difference in power in the first place.
9.7 CR versus 10.0:1 - not a big deal.
Side port exhaust versus PP exhaust gonna give you a little gain on the low end, but the PP exhaust should out-breathe it on the top end...better for your goals, IMO.
The thinner apex seals on the RX-8 engine is going to be suspect with that kinda nitrous levels - the early apex seal design is taller and thus stronger.


Unique? Yes.
Cost efficient? Not by a long shot.

Without getting into a big lecture on money management, bottom line is this...
You're wasting a lot of money just to brag about going unique.
You're young - there's a lot of smarter things you can do with your money.
The car is a money pit.
You might think you have a lot of money to spend right now, but it's an illusion.

I'm looking at a $10,000 budget to pull this off.
Unless you have the motor and trans sitting in the garage right now?
Do you have this kinda money to waste?


-Ted

Save the headaches of mounting in a renesis, having to manufacture a new dash cuz the tranny sits differently, and trying to squeeze more power out of an underpowered motor when you can....... (trumpets sounding):

TURBO SWAP!!!!!!!!!!

I have given this a lot of thought; I was at the bank to get a loan on one of the very few cars I like these days (new Civic Si), and they want 14.9% interest on a $20000 loan. Car dealers are no better. Canadian manufacturers gouge at least 25% versus american prices, and quite frankly I don't think any new car in Canada is worth it. That being said, no I don't have the Renesis engine, but I do make the money for it. I make at least $1500 per month in disposable income. It just sits in my bank account until I figure out something to do with it. Not many cars excite me anymore. I drive 350Z's and G35 coupes frequently at the dealership I work at, and they don't even do anything for me despite having a $55k price tag. I figured that my FC built to my liking could at least do better than a G35.

And for the record, I don't think I've ever seen a sports car that was cost-efficient. Most of them qualify as money pits, too. I figured at least $20k for the mods I listed. By today's standards, that isn't even that much to spend on a project car.

good luck!! But why re-engineer the wheel when you can just roll with stock plus and get the same thing plus a bike and a boat. Chicks love the bikes and boats!!:)

+10

+50!!!!!..... why blow 20k on a renesis that won't be near as fast as a 13bt for 5k (maybe!) and if you are willing to blow 20k, why not go real exotic and get a 20b, or 13b-re?

Because that's what everyone else is doing. Plus isn't the 20B swap around $20000 alone? My whole budget for a car with a few exotic parts is $20000.

No bike..I'm dumb enough on 4 wheels, and no boat since I couldn't use it.

Well I hate to break it to you man, but the reason everyone else is doing it is because it works. While it is expensive to swap ANYTHING, some engines are cheaper, more practical, and more POWERFUL!!!! You said that a g35 leaves you yawning, well when you spend the 20k on putting in the renesis, you are going to be SEVERELY dissapointed with the whole deal; and, when you get passed by a loud as hell 13bt blowing fireballs at you as he goes by you are going to say "Gee, I should've listened to those guys".......IMO

I'll second the 20B. You want to be unique there is a much better choice. It will be cheaper and you could run 350hp at the wheels very very easily. Pair up a nicely built and tuned 20B with a TII drivetrain and you may just end up spending 10K but you'll have a rare 20B FC that can run 12's on a bad day. You can find 20B's for $3k- $4.5k depending on the shape.

for that kinda dough, 20b. install, lightly mod. and your have reached your goals. oh and forget nitrous.

'nuff said.


/thread

I make easily twice that amount, and I'm twice as old as you are.
And I'd still wouldn't waste my money on such a project...
Save your money for something else.
A project like this will gobble up all that money and then some.

(I dunno if you're talking CAD$, but all my figures are US$.)

Whatever the case, good luck with the project.


-Ted

Hey RETed, F you! :flipoff: Hey RS200, F you! :flipoff:

I hate being broke. :)

thats your problem bro, get a better job.

This is why my car looks like ass.
This is why my car only has a stock turbo on it.

I used to dump a lot of money into the FC, but I haven't done that in a while.

Oh don't worry, I've got projects that is going to eat up a ton of dough!
Aftermarket wheels for like $1,000 a piece!
HKS T51R SPL BB...oops, did I spill the beans? :D
Fricken $3,000 turbo! :eek:


-Ted

Actually, I have a good job and plenty of money coming in.... Just an equal amount of bills and/or debt.. oh, and being married isn't helping.... :) But yes.. everybody needs a better job.

Good luck on the build though! I'm for everybody else with 20b! Renesis is a fun new motor and all, but that doesn't make it any better. Especially if you are looking to make HP. Even going 13BT-RE would get you more potential from what I've read.

Keep us updated with your choices!

:drool: Can't wait to see it!

in your own words, you have the money to pull it off, so why do you need validation? i say go for it. you're young! now is the time to do dumb shit and get it out of your system. financial ruin is not cool for anyone, but it certainly isn't cool at my age and when i look back at things that i WISH i did and could have ended up where i am right now - just the same (only with better memories), i'd cry if i could any more.

just do it. be prepared for disappointment though. as a Renesis owner, the only Rx-7 i could see myself swapping one into and feeling good would be an SA or FB. they are fun motors and though their potential is limited (compared to the older 13Bs), they are pretty peppy in an Rx-8 ... much less a lighter chassis.

i'd offer whatever help i could on a technical front.

I have a legitimate question for you:
Have you ever driven a turbocharged RX7 with 250 rwhp or higher?
I'm asking this because for the past 2 and a half years, I've been driving my street-ported N/A 91 (blaze red------read my sig) and everytime I start to think that it's pretty quick, I end up realizing how much better I could have done if I only went with my friend's setup that I built which is a street-ported 13B-RE in his black 91. Most people go the turbocharging route for a reason. Because it's soo effective. I was bent on building a fast NA for quite sometime until I finally realized that I'll never achieve the type of powerband I'm looking for with my setup.
I'm just trying to help you save yourself the headache.

oh yeah ... i think it would be irresponsible of me to not say this ...

your power goals are not realistic. if the power is more important to you than the "exclusivity", then just get a 13B-T (REs and REWs are not needed for what you want) and engine management.

Exactly. I was talking to a friend about building a N/A engine and he finally got fed up and told me that no matter what I did to an N/A engine, a TII with a boost controller and exhaust will whip my ass any day of the week. Thats why I'm building a turbo motor.

not trying to be a wise-ass. really, i'm not. but why would you guys think otherwise? a turbo will always have a better powerband than an N/A of the same or lesser port-type.

I have to chime in here...

Please please please forget the Renesis. It will be such a headache and such a letdown if you somehow force yourself through the trouble.

13BT or if you really want something to knock your socks off get a 20BT ;)