The_7

i am considering swaping a 13b into my 83 gs and giving it a half or full bridgeport. first of all, do i need a different tranny or will the 12A tranny fit on it? also, will a bridgeport 13B 6 port perform significantly different than a 4 port? if so, what are the differences? thanks.

FuLLsMoKe

I'm pretty sure you'll need the 13b tranny... (not sure about this one)

But... for the diff between a 6 and 4 port... I don't think it'll make a bid difference. A bridge already has **** low end and that's what the 5th and 6th ports try to fix (in a stock port though). I don't see the 5th and 6th port heping much on a bridge.

FS

The_7

the reason i ask about the port differences is because its a lot easier and less expensive to get a 6 port 13B so i was wondering if there was a disadvantage

REVHED

The 12A box will bolt up and work fine.

Stick to the 4-port engine if you want a bridge-port. The primaries on the 6-ports are tiny. You'll have more potential and better results with the 4-port.

The_7

oh...well, it looks like im gonna bridge my 12A then unless i can find a REALLY good deal on a 4 port 13B

hornbm

actually you can just MAKE a 4 port 13b. A four port 13b can be made by changing the 12a rotors and rotor housing with 13b ones and keeping the 12a side plates. You'll need the 13b eccentric shaft too. Its pretty easy.

Oh and the deal with 6 ports are that its impossible to get any more than a very small street port out of a 6 port 13b.

The_7

COOL! is there any disadvantage of haveing the 12A end plates, etc. instead of the actual 13B?

hornbm

nope, absolutely none.

The_7

sweet! how bout this...all 12A parts except a 13B e-shaft, TII rotor housings, and renesis rotors ?

hornbm

now there is one part of this combo that I'm not sure about.

I dont remember if you can mix the 12a side plates with 86-95 rotor housings. The reason is because they moved the water jacket to the side plates from the rotor housings from 86 on. They changed it back on the renesis though.

All I'm saying is you're probably going to have to use GSL-SE housings and not FC ones. Oh yeah, and good luck finding counterweights for renesis rotors, LOL.

If somemone could confirm this please do.

REVHED

Spot on. You can't mix the housings because they moved the water seal groove from the rotor housing to the side housing when the FC came out.

1984special

Do Renesis rotors fit? It'd be cool if they did! And where do you get them anyways? Motors are hard to come by because it's so new.

rotary emotions

Renesis engines will bolt on to old style tranny, but if the internals will be interchangeable....???
They might, but considering their price, I wouldn't really start experimenting The apex seals might work though, depending on the width.
As for the gearbox: 12A box will do.
So you'll need old-13B (pre 1986) housings, 13B rotors (some discussion on what-fits-what), and shaft. Depending on the shaft and rotors, you'll need the correct counterweight and flywheel.

13B4port

i got a gsl-se engine that i'll part out for ya. eberything is i good shape except the rotors. one ofthem is trashed but the housing looks ok. pm me if you want anything ffrom the engine

The_7

i need 4 port housings because im doing a bridgeport. were there any 4 port 13Bs before 86 or was the se motor the first one?

1984special

Yes, the RX-4 (not sure if all or just one trim level) and the REPU had 4-port 13Bs. The GSL-SE was the first FI 13B and it was 6-port, not 4-port. IIRC of course.

The_7

ok so i can use the 12A parts with rx4 or repu housings.....what about rotors? will all 13B rotors fit? which are the lightest?

1984special

The lightest ones I think are 89-91 (S5) rotors? They're higher compression, and lighter. I'm not sure how to make them work in a pre-86 motor. On the Racing Beat Site, I think it says you need a 89-91 flywheel and counter-weight. Otherwise use the GSL-SE rotors. It also depends on cost.... do you want to throw a lot of money at this motor? Or are you like me, cheap bastard! (I'm a student, that's why)

The_7

yea im a student too (high school senior) .

but s5 ones sound nice, i think ill just save up for those.

i have been hopeing so badly lately that i would finish my car before i leave for college so i can have some fun and show it off before i leave but i dont know if thats gonna happen. if i can get a job and save money whereever i can i might be able to do it.

hornbm

mabey i'm not to clear on this. Sorry If i confused you, the plain and simple way to do this.

I'm not sure about the renesis rotors but you can use any 13b rotors in any engine as long as you have the front and rear counterweights to match.

So for a not too costly solution (most bang for the buck) Heres the setup I would do. Start with your existing 12a side plates, and clean those up, get some GSL-SE rotor housings. Get some S4 rotors. The reason why I say S4 is beacause the S5 ones are a bitch and a half to find, because everybody wants them. They cost alot more, and the truth of the matter is that they give you about a 4hp gain over the S4 ones. Just use the S4 ones. Get the shaft from a GSL-SE while your at it, and get a rebuild kit. Also get the front counterweight form a S4 motor, and the stock flywheel too, so you wont need the rear counterweight. Bottom line, dont bother with RX-4 or REPU parts, your NEVER going to find them. You'll find cheap S5 rotors before you find that.

You should have a nice powerfull, inexpensive 13b 4 port after this. Port it as you please.

LOL, I was in the same boat you were too. I was a senior last year and had to get my 13b swap done before college. Just get a minimum wage job, and save your paychecks, its how I payed for my project.

The_7

i thought se housings were 6 port?

yea im still looking for a job, hopefully i get hired soon

mwatson184

Or you could always buy a blown gsl-se motor, and port that one.

-Marques

1984special

Confusing yes?

The rotor housing is where the rotor spins, and the only port on that is the exhaust port. The intake port (the one you bridge) is on the endplates / sideplates, which is where the 4-ports are! I hope that clears it up...

I'm going to college soon, so my GSL-SE is going to rest for a while But in the meanwhile I'm going to learn how to ride a motorcycle!

hornbm

yeah I think thats where the confusion really is.

The_7

lol im dumb. if i wouldve stopped to think for a minute i wouldve realized that .

so i can use 12A parts with SE rotor housings, ANY 13B eshaft, and ANY 13B rotors? this might turn out to not be so expensive after all . i cant wait till i get get 650 dollars for a pineapple racing bridgeport

Id really like to learn too, i was thinking about getting a small one when i go to college next year but i dont think im going to be able to stop myself from putting 90 percent of my money into my 7

edit: also, what is a good price for 2 used SE rotor housings in good condition? id like to know around how much i need to save up before I post that i want them in the parts section.