A couple of questions
10-08-12, 01:42 AM
#1
A couple of questions
So about a month ago I picked up an rx7 for 1200 with a rebuilt motor and a **** ton of extra parts. Another tranny, replacement seat(even though the current seats are fine) 2 extra sets of door glass, another rear hatch(with the hole for the wiper!) a solid roof as well as a glass roof with the original cover for it, two t-18s-2s turbos, an intercooler, another carb that needs to be rebuilt, the list goes on. It runs like a dream and came with so many extra parts I could probably have this car for the rest of my life. That being said, I'm running a stock 12a with a rb header/exhaust, and its slightly lowered and has some wheels that aren't stock but pretty much look stock. One of my buddies said they came off an older nissan z. Other than that its pretty much stock though.
Anyway, I'm really excited to turbo it and get it on the track, but before I go out and buy another motor to start building so it can handle the turbo(its my dd so I need to build a second motor externally) I had a few questions. I'd like to go fuel injected, but I'm not too keen on the idea of buying a standalone ecu for efi, and from what I've searched, the best idea I found was to do a k-jet like the old audis/vws used, but I was wondering about the gsl-se, and if that was efi or something else? Bear with me, I'm a little newb with rotaries still. Also, if the 13b non efi is an option, I've read about the rotors being extememly weak in comparison to the 12a rotors. Are they interchangeable? I'm a little far out before I start the build, but I want to have it well planned out so I don't run in to anything unexpected and am stopped dead in my tracks. If I can stay with a 12a and somehow work in a fuel injection system I'd rather do that, but at the same time a 13b would be a lot easier to upgrade. Idk I have a million ideas bouncing around my head. Input please?
Anyway, I'm really excited to turbo it and get it on the track, but before I go out and buy another motor to start building so it can handle the turbo(its my dd so I need to build a second motor externally) I had a few questions. I'd like to go fuel injected, but I'm not too keen on the idea of buying a standalone ecu for efi, and from what I've searched, the best idea I found was to do a k-jet like the old audis/vws used, but I was wondering about the gsl-se, and if that was efi or something else? Bear with me, I'm a little newb with rotaries still. Also, if the 13b non efi is an option, I've read about the rotors being extememly weak in comparison to the 12a rotors. Are they interchangeable? I'm a little far out before I start the build, but I want to have it well planned out so I don't run in to anything unexpected and am stopped dead in my tracks. If I can stay with a 12a and somehow work in a fuel injection system I'd rather do that, but at the same time a 13b would be a lot easier to upgrade. Idk I have a million ideas bouncing around my head. Input please?
10-08-12, 07:42 AM
#3
82 FB
It says exhaust leak because you're still a "newb" as you say. i think after a certain amount of posts that will change.
You've got a lot of questions my friend but i can address a few.
First off, turbocharging rotaries is risky business unless you know what you're doing. Upgrade the apex seals for sure, and be sure you can keep it all cool and lubricated. Run heavyweight oil and premix for sure if thats the route you plan on going.
If you dont want to do efi, and know a little bit about carbs. a buddy of mine has a carburetor on a 13b, and its pretty crazy. fast and reliable. however i know he's spent a long time tinkering with jets and whatnot for the different barrels. If its going to be your dd then a carbureated rotary is your best bet.
From my own personal experience the 12a's are pretty reliable considering the fact that they're rotaries XD. Not as fast as a 13b but just as reliable.
Speaking of reliability, be sure you beat on the things, gotta redline pretty much every day, and let it warm up properly. thats why most of them crap out cause people are afraid to have fun in a car, and treat everything like a grocery getter.
Thats about all i got for you, feel free to pm questions or anything!
I'd be happy to help!
You've got a lot of questions my friend but i can address a few.
First off, turbocharging rotaries is risky business unless you know what you're doing. Upgrade the apex seals for sure, and be sure you can keep it all cool and lubricated. Run heavyweight oil and premix for sure if thats the route you plan on going.
If you dont want to do efi, and know a little bit about carbs. a buddy of mine has a carburetor on a 13b, and its pretty crazy. fast and reliable. however i know he's spent a long time tinkering with jets and whatnot for the different barrels. If its going to be your dd then a carbureated rotary is your best bet.
From my own personal experience the 12a's are pretty reliable considering the fact that they're rotaries XD. Not as fast as a 13b but just as reliable.
Speaking of reliability, be sure you beat on the things, gotta redline pretty much every day, and let it warm up properly. thats why most of them crap out cause people are afraid to have fun in a car, and treat everything like a grocery getter.
Thats about all i got for you, feel free to pm questions or anything!
I'd be happy to help!
10-08-12, 04:15 PM
#4
How long does it take to warm up properly? I usually give it about 2 minutes.. but seriously!? Redline it? Why is it that everything that would be bad for a normal piston is actually good for a rotary? Low octane gas, no synthetic, use redline if trans and diff, etc. I love rotaries lol.
I don't know much about carbs though, but I was thinking about picking up a 13b and first building it with that k-jet idea I was talking about to see if it actually would work, but if you say carb is better for my dd.. someone told me I would save way more on gas with a FI... thats my only main concern is that I already go through gas like a siv, just imagining how that would be with a turbo... if carb is better though than that saves me a lot of hassle and I can just go get another 12a to start the turbo build.
I'm gonna make sure the motor is nuke proof before I install a turbo, and run it at a low psi, probably 10. I want to follow the build guide for a 300whp n/a 12a, and then beef it up an extra notch and slap that turbo on so I can make around 350. I'd be happy with that lol.
I don't know much about carbs though, but I was thinking about picking up a 13b and first building it with that k-jet idea I was talking about to see if it actually would work, but if you say carb is better for my dd.. someone told me I would save way more on gas with a FI... thats my only main concern is that I already go through gas like a siv, just imagining how that would be with a turbo... if carb is better though than that saves me a lot of hassle and I can just go get another 12a to start the turbo build.
I'm gonna make sure the motor is nuke proof before I install a turbo, and run it at a low psi, probably 10. I want to follow the build guide for a 300whp n/a 12a, and then beef it up an extra notch and slap that turbo on so I can make around 350. I'd be happy with that lol.
10-08-12, 08:45 PM
#5
here's the age old theory that i've used: "boost in, apex seals out". if you turbocharge a stock engine, it will not last long. if you spend the $400 on building an engine to handle turbocharging it will last considerably longer.
the GSL-SE engine is fuel injected. it was called EGI, or electronic gas injection. i believe that it's L-jetronic. K-jetronic mechanical fuel injection may be difficult to run. i would suggest swapping in a later 13B that already has fuel injection. you will have to do some extra wiring and will need the matching ecu that came with the fuel injected engine originally, amongst running larger fuel lines, 8mm i.d. at minimum. its just easier and lest costly to swap in a later engine rather than retrofit your engine with mechanical injection. at that juncture, if you really want a turbo engine, you may want to install a TII engine to begin with.
the GSL-SE engine is fuel injected. it was called EGI, or electronic gas injection. i believe that it's L-jetronic. K-jetronic mechanical fuel injection may be difficult to run. i would suggest swapping in a later 13B that already has fuel injection. you will have to do some extra wiring and will need the matching ecu that came with the fuel injected engine originally, amongst running larger fuel lines, 8mm i.d. at minimum. its just easier and lest costly to swap in a later engine rather than retrofit your engine with mechanical injection. at that juncture, if you really want a turbo engine, you may want to install a TII engine to begin with.
10-09-12, 05:01 AM
#6
L-jet? The only thing that was keeping me from doing a tII was that I was told I'd have to basically get a new harness to run a 13b. I'm open to anything though. I'd rather not have to rip apart my car to make it happen. What extra wiring would I need to do? O2, maf, What else? Like I said I'm a little new to rotary still but already I favor it way over piston.
That was my plan regardless though. I'm not trying to put the work into turbocharging to have the motor blow a couple thousand miles down the road.
That was my plan regardless though. I'm not trying to put the work into turbocharging to have the motor blow a couple thousand miles down the road.
10-10-12, 07:47 AM
#7
82 FB
Unfortunately it does take that long to warm up the rotaries. I usually have my choke out all the way and run it until the needle is past "C" then I make sure to run her easy for a little bit till its warmed up a little more. Never push rotaries hard until they're all warmed up to proper operating temperature.
As far as carbs compared to EFI, its up to you. It IS a rotary, so being concerned about gas mileage is somewhat humorous to anyone who's owned one, lol.
If you do go turbo, be sure you upgrade the **** out of the internals. I've seen way too many good engines blow cause some noob throws some crazy amount of boost at a stock engine. Sure rotaries seem like they can handle a lot, especially with being able to rev really high straight out of the factory. Not gonna lie tho, boosted rotaries are somethin' else.
Good luck with the build! you could and should start a build thread so we can follow your progress!
As far as carbs compared to EFI, its up to you. It IS a rotary, so being concerned about gas mileage is somewhat humorous to anyone who's owned one, lol.
If you do go turbo, be sure you upgrade the **** out of the internals. I've seen way too many good engines blow cause some noob throws some crazy amount of boost at a stock engine. Sure rotaries seem like they can handle a lot, especially with being able to rev really high straight out of the factory. Not gonna lie tho, boosted rotaries are somethin' else.
Good luck with the build! you could and should start a build thread so we can follow your progress!
Trending Topics
10-10-12, 11:40 AM
#8
Putting a 2nd gen 13b in it is not bad. You need the left(motor) harness and you need less than 10 wires to run the coils if you are using the 2nd gen coil packs.
And if you only want 10psi then the stock 2nd gen motor can do that all day with a little extra fuel.
And if you only want 10psi then the stock 2nd gen motor can do that all day with a little extra fuel.
10-10-12, 01:56 PM
#9
**** I haven't been letting her get warm enough. My heart just sank a little. At least I have this build in the future. Thanks tofudrifter! As soon as everything is ready to go I'll probably start the thread.
Mandrake, I thought u needed a 13b wiring harness to run one in.an sa/fb? That the biggest thing keeping me from doing it is that I hate electrical and I'm not wanting to deal with rewiring the whole damn thing. Not to mention spending the extra 500 bucks on a decent harness on top of everything else.
Mandrake, I thought u needed a 13b wiring harness to run one in.an sa/fb? That the biggest thing keeping me from doing it is that I hate electrical and I'm not wanting to deal with rewiring the whole damn thing. Not to mention spending the extra 500 bucks on a decent harness on top of everything else.
10-11-12, 07:38 AM
#10
82 FB
Haha, its not ithe end of the world if you dont let her warm up. my own personal "rule of thumb" if you NEED to drive right away, dont accelerate too quickly and keep the revs below 3-3500, once that little needle is above the "C" its safe to kick it up a bit, no higher than 5k, then once its all the way warmed up, go ahead and beat the **** out of that little rotary. Again thats just how i do it, i dont ALWAYS follow it haha. just a lot that can go wrong if you fire her up and go drag on a cold engine.
10-11-12, 04:08 PM
#11
Oh well **** that's usually what I do anyway. I don't rev past 4 til its warm. So about redlining though. Is it so u can blow out any carbon deposit that's built up in the motor? Because I imagine that there won't be any detremental harm done by hitting redline. Only if you hold it there Right?
10-11-12, 08:22 PM
#12
Oh well **** that's usually what I do anyway. I don't rev past 4 til its warm. So about redlining though. Is it so u can blow out any carbon deposit that's built up in the motor? Because I imagine that there won't be any detremental harm done by hitting redline. Only if you hold it there Right?
Thread
Thread Starter
Forum
Replies
Last Post
SakeBomb Garage
Group Buy & Product Dev. FD RX-7
8
10-09-15 10:05 PM
ZaqAtaq
New Member RX-7 Technical
2
09-05-15 08:57 PM