Mark04

I'm thinking of getting a 13B, using 2 ITB's (Independant Throttle Body's),
upgrading Fuel management system, and water pump, moving Redline to 10,000 ,
It'd be pretty good. :P

BTW, ........Anybody got a cheap 13B for sale? lol

trochoid

iTrader: (6)

Be aware that going to itb's involves a lot of work, particularly with the fuel system mods and engine management if going FI. 10k redline, do you have any idea what mods are needed internally for those rpms, I have doubts you do. It requires a full rebuild and will double the rebuild costs for upgraded parts and machine work.

If you want a cheap 13B to build off of, keep in mind that it would be a core motor only, a total rebuild and correct high rpm upgrades are needed.

Mark04

yes, needs some work. my friend brad, who is a fabricator is convincing me that it's easy.
this from a guy who took a ford festiva body, and put in a Nissan Pulsar GTiR
AWD drivetrain, with the turbo SR20DET. so it's an AWD Festiva with around 500HP. it flies.

DriftFB

sounds like you have it all worked out.

Like Trochoid said, there is a lot of work to be done on this to make it work. Your friend may be a master fabricator, but is he a master rotary rebuilder? What ITB's are you going to use? Are you going to try using motorcycle carbs? What are you going to be doing about the OMP? Do you even know whats required to get a 13B into the FB chassis?

Your plan sounds okay when you type it out, but you have 3 sentences to describe months if not a year or two of work, lots of it custom.

steve84GS TII

Stock,safe RPM limit is 8500.

To run at 10K,make power at 10K,and not blow up at 10K, requires.......

Good porting (bridge or PP).
Hardened gears.
Proper bearings and rotors.
A GOOD rebuild and break-in.
Oil mods.
Precision balancing.
Correct type of apex seals.
A trans that can handle 10K at the input shaft.

Mark04

13B doesn't use carbs for one........
and I'm sure it'd take less than a month. He assured me that it'd be pretty simple.
13B Turbo Tranny, and pretty much any ITB's.
he said just make sure it has new Apex seals, and that you should use a light weight rotor, and overdrive the water pump pulley......make the gear bigger.

blwfly

iTrader: (4)

listen mate dont be sayin **** that aint true 13bs can use carbs..

FirebirdSlayer666

iTrader: (3)

This kid needs to quit living in the gaming world and step up to reality. To build a rotary to safely hit 10k RPMs takes money and time. It's nowhere near as simple as you think or what your "guy" has told you. You hit 10K in a 13B that you describe and you'll be picking apex seals out of your teeth for a month. You have a lot of learning to do before you touch anything on an RX-7

DriftFB

13B's did come carbed, but that wasn't what I was talking about i said, "what ITBs are you going to use? Motor cycle carbs?" Since some people use motor cycle carbs to build their own custom ITBs instead of buying from a company.

Still, where are you getting these ITBs? He says pretty much any ITBs will work. But do you realized they don't sell them seperately, or in 2 packs? And I can't think of any one that makes EFI specific ITBs for a 13B, so again, its going to be custom work. Pretty much any regular carb you get, like a delorto (sp?) or weber is pretty much, if not anything else, a ITB.

Rx-7Doctor

iTrader: (13)

Here says it all.

trochoid

iTrader: (6)

^^^^^ X2

diabolical1

iTrader: (3)

x3

DriftFB

I'm past the meter

kenn_chan

I just broke out my hip waders after his third post .

kenn

Mr rx-7 tt

iTrader: (5)

Well damn, I ran a 13b (4 port) to 10,000 rpm everyday on a stock rebuild with only a streetport and the bolt-ons and the motors always lasted 120,000 plus miles...I wish you would have let me know it couldn't be done.

diabolical1

iTrader: (3)

sounds nice. i'd like to hear more about this setup you had (year, parts, apexes, port timing, intake, etc.). respectfully, i'm a skeptic. what can i say?

anyway, giving you the benefit of the doubt, i still stand by what Steve conveyed. for everyone of you (people that have the apex seal gods on their side), there's probably a dozen guys that try it and are not so fortunate. furthermore, the original poster has thus far showed no true grasp of what he's up against - just an idea and friend who can make Festiva fast.

trochoid

iTrader: (6)

1st thing evey newb needs to learn is to NOT listen to thier piston friends about what they think a rotary can or can't do. There still so many myths and misinformation floating around, I'm dumbfounded some days.

Mark04

Be a sceptic as you like. it was just an idea. I was told it can be done, and that it's not hard. I've been told by rx-7 owners on the island that you don't need to do much work. I have no idea, it's my first rx-7.
It'd be a challenge.
If I wanted easy, I'd make my 200sx stupidly fast.
I understand RX-7's are VERY different, but I'm up the the challenge.

I was thinking about using a Holly Double pumper carb on my 12A.
would that work? or are there better ones?

Rx-7Doctor

iTrader: (13)

What other mods are done to the engine?

Mark04

none. no mods yet. just bought it.
planning to get a new carb soon, and new exaust system.

I really don't know where to start.

Mark04

oh, and the air pump is disconnected. stupid emissions. no power steering belt.,
planning on getting an electric fan soon too

Rx-7Doctor

iTrader: (13)

Well, the best I will offer you is to recommend that you do alot of searching on the forum with all the threads that have been done on this subject. Look at what people have stated about their particlular exhaust systems, carb set-ups, etc.....

When you get done you will not only be alot more knowledgeable but will know exactly what you are getting into and what to expect from the results of your mods.

I also recommend before you do any mods on the car that you go thur the car and safety check the brakes, suspension, and steering. Then make sure all the tune-up areas have been addressed.
Remember the more basic work you do on the car will prepare you for the mods that you want to do to the vehicle.

Mark04

well, car is pretty decent. has great suspension, and steering, and tranny.
Just gotta get brakes looked at. When I bought it, it had a new clutch, and new rear Diff. there are over 5 holes in the exaust piping. I need to get exaust built.
Should I go 2.5", or 2 and 1/4"?

steve84GS TII

Forgetting about the mechanicals of the engine for a moment......
If the engine has no work done to it,then dont plan on making any power at those high RPMs,no matter what carb you install.You need porting to get more air in and more air out,just like with any engine.
The stock ports are not going to flow enough to let the engine breathe above 7000rpms.....you might be able to rev past that,but there wont be any power in it,and youll just be punishing your engine.Porting requires a full engine teardown,and selection of the right porting wll determine where in the powerband the engine will make its power,as well as driving and idling characteristics.

There are 3 basic types of porting.As you get more radical,the powerband shifts higher and higher up,but lowend torque,fuel economy and idle quality will get worse and worse.Thus,the narrower your powerband gets,the worse the car is to drive on the streets.

Streetport: An enhancement of the stock port design,this is good on stock,mild or turbo engines to gain a little more breathing.Can still idle like stock,if you dont get too aggressive,but a big streetport can affect idle and lowend a bit.Makes good power within the stock RPM range,and allows for good power to around 8K rpms provided the intake and exhaust systems are enhanced.

Bridgeport:Adds another small intake port in the irons,parallel to the stock intake ports.Improves topend power and shifts powerband furthur up,but greatly affects idle and lowend,since there is now a lot more port volume and it wont flow well until the engine is revved up.Can be done as a half-bridge,if lowend and idle need to be retained,but a full bridge will make more topend power and allow you still make HP while at those RPMs. A so-called J, or Monster bridge will give the most power,but will also affect driveability and idle the worst.It can also affect engine longevity greatly since the water seal area will be violated and the high rpms needed to make it breathe,will increase engine wear and stress.Power in the 7-10K range,depending on the size of the ports.Extensive intake and exhaust mods are needed,as are internal mods like apex seals.Stock steel seals can destroy the housings under sustained high RPM use.

Peripheral port:Provides the engine with a big,direct intake port just like the stock exhaust port.Deletes the stock side intake ports,and focuses on high RPM power only.Great on the track,loud and painfully tempermental on the streets although there are some who have done it.Because of the large port,the engine will be flat on its face until you hit 5-6K or so.Extensive internal mods are needed for the engine to hold up,since the majority of its life will be spent revving well past the stock redline,up to 10-12K rpms in order to get the huge ports flowing.There are variations of the P Port which can increase midrange and/or spread the powerband out a bit,but that almost always results in a loss of topend power or limiting of the max RPM that still makes power.

Basically what Im getting at is this......sure everyone wants to rev their engine to 10K.Its fun and cool and makes you feel badass.But if you dont do it right and prep the engine for that kind of use(,porting,internal strengthening and bolt-ons),you wont be making any power up there,and the engine will just be getting thrashed, to satisfy your desires for high rpms.It might physically rev to where you want it to(for a while),but shifting sooner and using the powerband that stock ports provide,will result in a faster car.

blwfly

iTrader: (4)

very nice examples you got mate