Wankeled

Hey guys,

I'm buying a newly 12A rebuilt engine soon and wasn't quite sure which setup to go with...

I've done my research but haven't come up with a definitive answer so I'd like to ask those who have experience with either of the two different setups:

I'm deciding between getting my 12A streetported with a turbo setup or get my 12A bridgeported? (I thought of the peripheral port but I hear it's not meant for a daily driven vehicle)

Anyway, I want to try to get 200+ hp out of this setup at least when I'm completely done but it still has to be reliable enough to be driven everyday.

I've read that "bridgeporting" is the best for power gains and it is still street driveable but can I get this turbo'ed also?

What do you guys suggest I do with my new 12A engine for power?

Your opinions would be greatly appreciated.

Thanks!

(PS. extra info: I have an '85 GSL and will be getting an entire racingbeat exhaust system (soon), possibly with either a 465 Holley Carb or Weber 48 IDA (soon) and then go direct fire ignition. So, if you want to take that stuff in consideration, there you have it)

Tyrael6666

Turbochargers can be very hard on an engine depending on what boost you run. With any port you arnt going to be harming the longevity of your engine really. With a bridgeport you will need pricey 1 piece apex seals. But then a custom turbo kit isnt cheap either lol. Oh if you do go turbo remember buying that racing beat header is going to be a waste of money cause you need a turbo manifold. Your best option is to asses what price you are willing to pay in total, and keep in mind turbos do more damage to an engine than keeping it N/A.

thekyl

HUmm I dont know but from what I have heard that the 12a rotars cannot really handle the pressure of the daily driver from a turbo. And hypatheticly you can turbo any thing that has a intake and exhaust. If you want high boost pressue from the turbo you need something like TBI or FI but you can get high performance floats for most of the brand name carbs. Now what I was thinking about doing was either making a customer 12a rotar forged from better aluminum or something but havent really decided what would be best. But best thing to do for reliablity I have seen is just buy a 13b and go from there.

diabolical1

iTrader: (3)

check in the archives. you'll get all you need to know about turbos and porting options there.

keep in mind that the best damage control is YOU, not choosing which route to take. high RPM can cause just about as much damage (or more) as boost. maturity, tuning and maintenance are the real key factors.

cpt_gloval

iTrader: (1)

i would be partial to boost myself. you get more torque with boost all across the rev range than you would with a bridge. plus you don't have to rev it up to like 10 to get any sort of power out of it.

Eriks85Rx7

y not super charge it?

85rotarypower

What was said about a bridgeport is true. Many special parts have to be purchased to withstand the 9000 rpm redline of a bridgeported engine. Bridgeports also don't make much torque or power down low. Most of the time, I believe the power is made 6000 rpm and up. but I don't know enough about them to say either way. To me, a bridgeport is not really daily driveable so I never looked into them much.

As for a turbo, with a streetport and a mild amount of boost, your reliability wouldn't be any different than a bridgeport. It might even be more reliable. Stick about 7-8 psi of boost on a streetported 12A and your looking at about 230-260 hp, same as a bridgeport, but with LOADS more torque in the bottom end. You also won't need to rev the **** out of it to get power from it.

diabolical1

iTrader: (3)

i totally agree with this and it's usually the point i'd try to make, but i've decided to let people decide for themselves because they're going to do what they're going to anyway - the low-end issues, the exhaust, etc.

PaulFitzwarryne

Street porting a 12A then adding a turbo will get you around 220hp @ 6800rpm on a 6-7psi boost and have a reliable streetable engine.

Bridgeporting a 12A NA will get you 220-240hp@8,500rpm with an engine primarily set up for the track but usuable on the street if there is no heavy traffic. There is no reason why it should be unreliable in the short-medium term, however engine wear will be about a third higher with a life of around 50,000miles if less than 10% is flat out competition. Yes you could add a turbo.

The real question is, what is the use going to be?

TurboSE

stupidchargers are 4 sisis!

WackyRotary

I used a 12a bridgeport on the street. Its not all that good- except when you bring it to 8000+rpm, and that is bad for the stationary gears/rotors/etc. I would go with a turbo 12a streetport as I have been= stay in a good rpm range, quieter, and drivable.

Having said this, I just pulled my turbo off my car - going back to n/a streetport 12a(headers ofcourse) because I am having a hard time justifying paying >$2.20gallon of premium gasoline and getting 130-140miles a tank! The n/a will get closer to 18mpg the way I drive with the headers. Both a 12a streetport turbo and a 12a n/a bridgeport will yield 12-14mpg on average from my experience if you are going with the correct carb. The major difference is premium is more expensive, but I would go with a streetport n/a on the street before a bridgeport any day. ESPECIALLY if you drive in a busy city most of the time- bridgeports are notrious for attracting the wrong attention.

FMYStreetRacer

i used to have a 12a bridge-port in a 79 rx-7. i had mikuni side draft carb and rcing beat geader ewxtended. it sucked *** as a daily driver. but at the races it was fun as hell. i wouldn't suggest it as a daily driver, and i like some rough driving cars. when i was on the highway the over lap was horrible. i drove it once when i first got it to the first flrx7 bbq. after that i tried to never take it on the highway again. i'd say go with a street-port

jays83gsl

What about a 1/2 bridge?

thekyl

You know what I would do now that I have my 12a's appart I was thinking that maybe I would make a custom Fuel injection or have one made. Humm what do you guys think do you think the 12a's design can take the FI setup? I'm not talking turbo just FI. Maybe low boost from turbo but that wont matter much. Humm what do you guys think?

jays83gsl

I see no real advantage to putting an FI setup on the 12A.

PaulFitzwarryne

An efi set-up has real advantages. Comparing a tuned Nikki Carb with a Haltech, there is increased power throuhout the rev range, around 5-6% higher at peak revs and up to 10% low down. It accelarates more smoothly and is easier to start cold. Fuel consumption is marginally better.

Taking as an example a well set stockport [good headers/exhaust], fitting an efi will give you an extra 7-8hp above a modified Nikki/Weber. However, the efi system does not come cheap, and for most people it will not be worthwhile. The $ per 1hp increase is too high.

Pele

iTrader: (28)

I'd like to see people's thoughts on this...

What's it like a street port down low and bridgey up high?

PaulFitzwarryne

The worst compromise, dissatisfaction with both ends. As much fun as a virgin with tooth ache.

14,5

l have a 12a streetport supercharged making 180hp to the wheels at 9psi

Pele

iTrader: (28)

There's always the tailpipe.

diabolical1

iTrader: (3)

perhaps one of the best comebacks i've seen in recent times.

Pele

iTrader: (28)

No. it just shows that I've been hanging around the Lounge too long.

I need to find some nitrated R5 housings, get around to picking up that core SE engine, and get my ******* FB running so I can come back with videos and such...

Pele - PIIDB!

diabolical1

iTrader: (3)

LOL

thekyl

Yea I think the custome FI on a 12a would be awsome chipest block and options on engine parts and the benefits of the 13b with FI. I think it would be margonaly better for a city daily driver and even possibly a turbo for more Ponnies but even with a lower constant boost at like 7-9 psi I think the 12a would hold up really really well. Does anyone know of a system that has been setup this way? I was looking into having a system setup or built I have some aluminum that me and a friend are going to try and work with and make a FI system. humm any ideas on what injectors to go with and should I go duel injectors on the TII injection system? humm any thoughts.

PaulFitzwarryne

Not recommended unless you live in an emissions testing state.