'87 turbo II

iTrader: (1)

Ok, I searched around for this, so I am sorry if it's been covered, but it's pretty application-specific. I am picking up a GSL-SE 13B block and full accesories soon. I currently have a GSL-SE block in my car, running with a Dellorto DHLA 48. I want to take the 2nd engine, and put massively bridgeported 12A irons on it. This will all happen in about a year when I save up for the rebuild and a new clutch (why not while the engines out?)Now time for a list of questions.

-Should I buy higher output fuel pump, and run the stock SE- EGI? I don't want to purchase better injectors and what not on top of the price of the rebuild and clutch and what not. I don't htink the stock fuel injection can keep up with a large bridge so I'm thinking the DHLA is my best bet.

-Can I use the 13B middle iron since it should be the same as a 4 port for the possible use of an FC sub-frame swap with the 2nd gen mounting spot on the SE block? Will it port the same as the 12A middle iron, is it the same size as the 12A/4-port 13B iron so a standard 4-port 13B UIM and header will bolt on?

-I know I will need to dyno and fine tune the jetting when I set up the Dellorto for the bridgeport, but does anyone know a good starting place? Idle jet size, Main Jet size, venturies, pump jets, etc.?

-Is there anything else I should know? Should I port the exhaust ports too? I've never done porting before, will a template keep me safe, or should I pay to have it done by someone?

PercentSevenC

You'd need bigger injectors.

You can, but they can't be ported nearly as big as a 12A intermediate plate.

You mean LIM? The UIM is the same for everything pre-'86, assuming you're talking about the RB manifold. Yes, intermediate plates are all the same width. If they weren't, you'd need a different eccentric shaft.

If you want power, then yes, you have to port the exhaust. Templates won't "keep you safe", but porting exhaust is not difficult. Read some porting threads to see how it's done.

'87 turbo II

iTrader: (1)

Thank you, and yes I meant LIM. I'll probably go with a 12A intermediate plate then, and if I want the Fc sub frame, I'll do something about the mounts when that problem arises.

Any ideas on what kind of power I'd be making with the DHLA 48 on a bridge setup with my RB header, straight pipe and Rb muffler or are there too many factors?

4portgsl

I'm building a 4 port 13b using 12a side plates and 13b rotors and rotor housings right now, im streetporting the whole shootin match. Its my first port job and i used racing beat templates and a video from mazdatrix to get it done, they came out pretty nice. If your going to bridgeport your side plates, you need to port your exhaust too. A race exhaust port is probably your best bet. As for using the gsl-se center iron, the stock SE center ports are teeny and may not port out as well as the 12a ones. The dellorto is also probably your best bet for feeding that monster, but when it comes to tuning recommendations, i haven't a clue. Good luck with it.

pinoyremix

jetting im not sure on..i checked all my sources and can't find correct for a bridgeport 13b,..i will tell you, you will get great power..

PercentSevenC

190 to the wheels at most. The problem is your RB muffler. Collect your header into 3" and go straight through after that.

You're aware of all the high-RPM mods you have to do, right? You can't just take an otherwise stock engine and bridgeport it. Well, you could, but it wouldn't make any sense.

OneRotor

iTrader: (3)

+1

don't bother with that exhaust combination. I'd suggest looking into the RotaryShack SS header with the cross over pipe. It is very similar to the SDJ header, and it will make more power across the board than the RB unit. I think people go with the Borla XR1 for a resonator, and I'm not sure about what they use as the muffler. Go with full 3" SS piping for a bp 13b with a Dell. It will be loud, but you'll choke off the exhaust with anything smaller. Good luck.

'87 turbo II

iTrader: (1)

High RPM mods? you mean hardened stat gears, something having to do with oil pressure I'm assuming and stuff of that nature? I wasn't aware that the engine would be running to higher RPM than usual at all. I just thought the porting would add more power throughout the general upper powerband (except for the low end)

I thought the RB road race header flowed really well, the muffler I understand can be restrictive, would it help to route the road race header to a custom true dual setup with some steel wool-packed straight through mufflers?

any good links to threads that may help me better understand this? It seems I'm not 100% sure just what I'm in for.

'87 turbo II

iTrader: (1)

Ok, I'm mad at myself for not doing further research before asking dumb questions. It seems after looking at this page:

http://www.mazdarotary.net/porting.htm

my best bet for my knowledge level and financial ability to run supporting mods is an extended port, or I guess an aggressive street port. I don't have the money to start changing the stock internals much other than the ports themselves, and I still want my current exhaust(RB RR header, 2.5 in straighty and Rb powerpulse muffler) and intake setup(DHLA48 RB UIM, and will switch to 4port 13B LIM with the 12A side housings) to be sufficient for letting the engine breathe getting a custom true dual exhaust off the road race header is very do-able later on if it helps a lot.

Does a budget of around $2500(this will take me roughly one year to obtain) including Racing Beat's $1300 rebuild kit seem like enough to tackle an aggressive street port and make good power? I probably should mention that the car is a daily driver/autocrosser that currently gets about 13MPG so I am not scared of MPG as low as 8 or so, noise doesn't bother me, and I'll probably pick up a beater in a few years to further make the 7 harder to tolerate on a street.

Sorry about all the questions, and sorry if I seem a bit dumb on the subject. bnut thank you to everyone helping me.

PercentSevenC

If you're adding overlap, I don't recommend true duals. Best keep it collected.

orion84gsl

iTrader: (5)

Shop around for your parts. You can probably do it cheaper than you think. Atkins Rotary has the master rebuild kit for under $800. http://www.atkinsrotary.com/index.php?pag=5. Shop around for the internals and save carefully. You can have whatever you want, it just takes patience. It may end up taking a little longer but you'll kick yourself later if you don't get what you want in the end. And you will need a better flowing header than the RB unit for a bridgeport, and you'll see gains over a streetport as well. The RB parts are designed as a compromise between power and streetability. Quiet and a decent bump in power, but not to be compared to a completely free flowing unit.

OneRotor

iTrader: (3)

Get the Atkins kit. Take the $500 that you're saving on the other kit, add $200, and get yourself the RotaryShack SS header. If you end up needing an e-shaft, get the RX-8 one. It's cheap (~$135), lighter and stronger than any of the n/a 13b shafts.

SLIDN7

Im doing a bridgeport with overlap escape on my 12A and i got all my internals and rebuild kit from atkins rotary, cheaper and beter quality than any other site, they even got the new cryogenic apex seals.

4portgsl

Atkins is where i plan on buying my rebuild kit from, i hear good things. They have different "levels" to their rebuild kits, which is nice.