13b-re questions
 

Ive searched here and google and gotten no clear or undisputed answers if any at all..I have some real basic trivial questions about the 13b-re.

1) how much hp does it make stock and at what boost?

2) what size are the stock injectors and how much boost/hp can they support.

3)ive seen several people mention the stock fc radiator not being enough for the RE is this true or BS?

I have more but as usual i forgot them as soon as I started to type this thread.

1) I forgot
2) 550ccx4 if IIRC
3) It can run with it, its just not always suggested (sorta a bandaid).

So a koyo or fluidyne is recommended?

Also, on a 13b-re with a s5 turbo will a stock s5 exhaust match up?

No one?

230hp, 217ft-lb, 11psi. Less power than an FD but with a broader spread of torque to suit the Cosmo's nature.

Two 550cc/min side-feed primaries and two 550cc/min top-feed secondaries, which will support 290-300hp if fuel pressure is maintained (i.e. with a decent upgraded pump). Injectors don't support a certain amount of boost, they support a certain amount of power. How much power you make at a certain level of boost depends on the turbo.

Similarly, how much cooling you need depends on how much power you're making, not what engine you use. Racing aside, the stock radiator usually handles mildly modded turbos fine. You need to use a radiator that will suit the power you plan to make and how you're going to use the car.

Yes, as long as the custom mounts required position the engine in the same place as the old engine. I hope you're not keeping that exhaust for long... ;)

^^^^I didnt literally means tock exhaust, i have a RB downpipe and aHKS midpipe and cat-back. I bought it for my N/a turbo project but i sold that and am currently buying a fc with a 13b-re swap. So i need to know if it was still useful.

Sorry for the turbo confusion I know what I mean it just came out wrong. I was trying to ask, at what level of boost would you usually upgrade the secondaries? Im -planning on running around 12-14 psi, do you think the stock 550's will work or should i upgrade to 720's. ALso will fc top fed injectors fit the secondaries and FD side feds the primaries?

Im confused now, another site states that the 13b-re shares the same injector sizes with the s6 which is 550's & 850's. Im sorry for all the dumb questions im just tryign to learn what i have.

I searched for a whole day and turned up squat before i decided to post(assuming i would be flamed)

Im still tryna find answers to these questions.

Ah, that's good. ;)

A stock turbo on a stock FC engine is okay at 10psi but beyond that you should be checking fuel injector duty cycle to check it's not too high. Above 85% you definitely need to upgrade. The JC engine should breathe a little better so it'll make a bit more power (and hence need a bit more fuel) on the same boost.

Personally I wouldn't run a stock turbo at that much boost as they're well past their efficiency peak and the compressor outlet temps start to go up pretty quick. 12psi would be the as high as I'd go, but yes you should upgrade the injectors so you can run rich enough to keep combustion temps safe.

The FC and JC secondaries are the same. The FD and JC primaries are the same. The FD primaries and secondaries are interchangeable.

I though the same thing a while ago but have since been corrected.

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/size-13b-re-injectors-154733/
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/13b-re-cosmo-secondary-injectors-upgrade-491911/

Also what is the compression of the stock rotors? and as anyone sur eof the stock boost cause 10psi sounds kinda high.

CR is 9.0:1, same as all post-89 Turbo rotors. Stock max boost is 11psi like I said, which isn't all that high.

The info's from www.dmrh.com.au. This guy knows JC Cosmos better than anyone outside Japan.

^^ thanks man, looks like a pretty informative site. I searched here and google for days and couldnt find any real helpful 2-rotor cosmo info. Im gonna go read through it all now :)

Im still a bit confused about the psi thing but maybe its just my lack of turbo knowledge/over expectations.

If the s5 TII makes 200 hp at 7.5 psi I woudl thing the re with the larger port/runners ect would make a bit more than 230 hp at 10-11 psi.

I think you're in over your head and should drop the idea of trying to do this.


-Ted

Im not trying to do anything im buying a completed swap and just trying to learn about what i have. Ive been searching the forums and google for more 13b-re specific information and have ordered maximum boost, by corky bell along with other recommended reading to learn more about turbo setups in general.

We all have to start somewhere right?

The S5's max boost is 8.3psi. And "max boost" is different to "boost at max power". Most turbo'd engines receive max boost in the mid-range and less at higher revs where peak power is. It's a deliberate design feature used by lots of manufacturers to get good mid-range performance without over-stressing the driveline at high revs. Note that the JC engine makes 11% more peak torque than the S5's, and that peak occurs in the mid-range where boost usually peaks.

http://fc3spro.com/TECH/SWAP/COSMO/13b-re.html


-Ted