SwiftTone

I've recently been interested into FBs. I like almost everything about them except their power. they look great, with a few adjustments( airdiam/front bumper). My question is. How hard is it to get to 200hp+ with a 12A engine without turbo/supercharger/NOS. I'm want to keep the engine carbbed.. I've heard from someone that you can carb a 13b engine. How hard is it.

My budget when I do get a FB will be $2000 on power mods.

Thanks in advance guys.

exodus82

Buy a street port 12A
they're about 2500
but they have 220hp right out of the box

Directfreak

iTrader: (2)

No they don't.

Crack Monkey

What he said. A big street port with the right carb (or EFI) and exhaust can make 200hp. Probably cost you more than $2000 to do properly.

With a 12A, 120-140rwhp isn't too hard. And it really is a fun car to drive. Don't let the lower power output put you off the car.

hybridracer

Theres no way a 12a with just a street port could make 220 "out of the box". Someone misinformed you my friend.

SwiftTone

The restrictions will be cats, and exhaust.

Is the street port including the engine or just the porting itself.

I sound very newbie.

SwiftTone

Reliability is also a must.

hybridracer

Good god for 2500 i would hope it included an engine If not that had better be the best damn street port ever made.

knight1976

This is what i have heard can be produced with the 12a:
A stockport 12A with every bolt on(intake, exhaust, etc) can make 150-170hp (at the flywheel)
streetport 12A with every bolt on(intake, exhaust, etc) can make : 150-200hp (at the flywheel)
bridgeport 12A with every bolt on(intake, exhaust, etc) can make : 170-250hp (at the flywheel)

Sounds accurate depending on the shape of the motor and the porting.

Gurus correct me if im wrong here.(and you know they will)

SwiftTone

how reliable are the bridgeports, how about streetport

SilverRocket

That's extremely optimistic. 150hp is about the max.

You won't make any power at all without a straight-through header exhaust system. Look at Racing Beat, it's pretty much the only thing worth running.

Every aftermarket carb (which you will need to make anything more than 130hp or so) completely deletes the entire emissions control system, vacuum advance, etc.

So if you have some kind of visual inspection emissions test, I don't think you have any hope at all here, as everything needs to go to make any power. However, if all you need to do is pass on the cutpoints, maybe you can get away with welding some kind of custom highflow catalytic converter in your system.

I think passing emissions could be a challenge for you.

Here's my take on what you're trying to do:

If I were you, and wanted 200hp reliably with a carb, I would go with a 13B. You're going to need to have a bunch of work done on the 12A anyways, why not transplant a 13B? You'll want a 4-port 13B with some kind of big carb like a Weber 48IDA. You'll need a good fuel pump and regulator of course. There's lots of info on such transplants around the net, I'm sure you can find a lot out with some research.

You can make 200hp from a 13B more easily than from the 12A, without needing to port it as much or rev it as high. You said you need streetable exhaust and cats - in that case, I don't think you'd be taking much advantage of anything bigger than a streetport - bridgeports, etc, need very high flowing, loud exhausts (and are more expensive.)

I personally think $2000 is a little low for what you're talking about, at least to do it properly. As well, when you have 200hp, you're going to need better tires, brakes, suspension, etc.

If you like FB's, I would go for more of the balanced package approach; and as already stated, don't underestimate a light GS model FB with 150hp. It's about as fast as a stock TII until high speeds, in my experience. Lots and lots of fun, and reliable as anything when set up properly.

SilverRocket

The thing is, as you go for a more aggressive port, you move the powerband up higher. Depending on how it's done, and the exhaust, a bridgeport probably makes peak power at 8 or 9k, makes nothing below 4k, and idles like ****. And uses shitloads of gas.

Those are guesses though, I'm no expert on ports lol.

Another thing is, if you want to rev to 8-9k all the time, to take advantage of a bridgeport, you'll need to do some internal modifications to the motor, to prevent things like rotors contacting the housings at high rpm, etc. That stuff is not cheap.

I think to really do a bridgeport properly and somewhat "reliably", it would take more than the kind of budget you're talking about. You might want to call Mazdatrix or something, and ask them how much a bridgeport motor with appropriate modifications would run you. My guess is more than $2k, and you haven't even got a carb or exhaust yet.

Manntis

the 13B is 130-135 HP stock (depending on US, Californian, or Canadian specs) and with just intake and RB exhaust can get up around 150-170HP.

Then there's turbocharging, porting, etc. on top of that.

I'm having trouble understanding why someone would want to start with an engine with a 30% power deficit as opposed to the higher displacement, turbo-friendly 13B.

Then again I still don't get why someone would carb a fuel-injected engine. Seems like yestertech to me

851stgen12a

ok for $3500 pineapple racing out of Portland Or, can build me a large streetport that makes 220 hp at the flywheel. this does NOT include carb and intake. in order to make 220 hp he said I will need a completly upgraded fuel system (with surge tank) and need a minamum of a 48 ida carb and manifold.

220 Hp is possible but it isnt gonna happen on $2500.
Well i take that back, you possibely could but the workmanship isnt gonna be real great. and you motor is probobly not going to be very reliable

DriveFast7

iTrader: (1)

225hp is the max you can get out of a carbed streetported 12a. it will take a 48mm or larger carb and a WIDE OPEN EXHAUST with no muffler. The noise is incredible and will get you arrested in no time.

With the proper free flowing mufflers keeping noise reasonable, plus proper tuning, ignition, etc you should expect 185. Still not cheap.

I do trust Rob @ pineapple, he's building me a 12a Jbridge for the racecar. Wish Mazda would get their ceramic apex seals in stock earlier......

-bp-

851stgen12a

Going ceramic apex's huh?? tell me how you like them. considered it for the motor im gonna build but $2000 is a little to much for apex's.

DriveFast7

iTrader: (1)

ceramics are overkill for n/a street applications. they do add more power and have almost no wear so they're a one time purchase as long as nothing dumb happens to the motor.

go iron, cheap, seal well, good enough.

i used an iron sealed 12a streetport for track schools for two years. seals were alright up to 8500rpm which is a little over my peak hp so it turned out well. and it was a mild exhaust port.

JEC-31

Quote: "I'm having trouble understanding why someone would want to start with an engine with a 30% power deficit as opposed to the higher displacement, turbo-friendly 13B. "

Because 12As are cheap, plentiful, and reliable. I have 3 lying around, and plan tweak out at least one of them.
But if I accidentally pick up a cherry 84/85 13B or a 89-91 TII then you know what's going into the car!

SilverRocket

Because the carb is an easy way to make more power than the stock EFI does. RB Dellorto and exhaust makes 180hp on an SE, totally stock motor. You can't argue with power

Manntis

But you're comparing a modded part to a stock part.

A mod carb makes more than stock fuel injection does. Isn't that the point of putting on the mod in the first place? But what about modifying the fuel injection?

Let's say you replace a12A carb with a RB Dellorto, f'rinstance. More power, yeah?

So in an apples-to-apples comparison, wouldn't you replace the EGI with an aftermarket injector/fuel managment software/fuel pump combo?

SilverRocket

Manntis,

What you're talking about might be nice, but how much does it cost, and do you need a laptop to tune it, can I fiddle with it with my college student toolkit in my driveway?

A Dellorto kit costs $300US, plus an extra hundred or two for rebuild kit, new air filter, misc parts, fuel pump and regulator.

How much does an aftermarket EFI and Haltech cost? I'm betting it's a hell of a lot more than that. And is it easy to install? How about tune and mess with in 5 mins with a screwdriver?

See what I'm getting at? Obviously an optimal EFI system is gonna be superior to a carburator, and have a way nicer power curve than a big sidedraft, but only if it's set up right, which isn't a piece of cake. And it's gonna cost a shitload of a lot more.

So that's my reasoning, and that's why I would probably go that route if I got my hands on a 13B. Now if I had unlimited cash flow and wanted to learn about EFI and tuning, maybe I'd be interested in the other route. But for a cheap, simple and easy to tune power mod, I think the carb is the way to go, for my needs, personally

So now do you get why someone (like me) would want to carb a 13B?

diabolical1

iTrader: (3)

well, i think it all comes down to a matter of philosophy. some people are willing to spring for EFI (or upgraded FI) and some aren't. however, some of those same people that would complain about the price of a motor or the FI they should put on it, would drop 2G'z on rims. see, what i mean?

personally, i agree with you. i prefer FI, and as soon as i figure out exactly what i want to do with my car, i'll probably be saving towards a good system. for now, i run my Dell, it is a bit of "yestertech" as you said ... but it's also tried and true ... and for the cost, a very viable alternative. besides ... it's a lot less headache when it comes to tuning.

diabolical1

iTrader: (3)

oh yeah ... and to give my input on the original question. definitely start with a 13B. and above all ... wait until you can work with about $1,000 more in you budget. you can absorb some of the cost up front, by doing things that will transfer to the 13B (fuel system, "aft-header" exhaust, carbies, ignition, etc.) ... but definitely wait until you can get more money.

Manntis

I see your point, SilverRocket - and diabolical1, I like your quote about the 2k rims.

Me, I do both. I bought rims, but also bought a full exhaust, etc. And I definately prefer FI to carburetion, but it's just that - a preference

Wankelguy

Well, some very interesting views here!
Personally, I like the idea of a carbed 4-port 13B with a conservative streetport and slightly reworked stock 13B carb for up to about 185 HP. All you need to make it run is 12 volts to the coils, a breather, a tank vent, and a vacuum advance line, and to hell with electronics. Plus, I like the way the 13B comes on stronger through the midrange. Eminently streetable, and possible for under $2000!