B210 headers vs. manifold

[Ozomatli]

HI, im debating if its better to stick with the exhaust manifold, my car already has or if its better to get headers?

What im trying to accomplish is to get somewhat good engine performance, but at the same time great gas mileage, i hear arguments from both sides, and they bot claim the same (great engine/ great gas mileage)

but im not sure if its referring to bigger engine?

What i would like to adapt (headers/ manifold) to is my 1977 B210 with a 5 speed transmission and a Weber 32/36 DGEV Carburetor

 

Any other ideas to achieve these two goals is welcomed!

 

Thanks for the help!!!

[metalmonkey47]

I wouldn't recommend it. You really won't see a benefit. In fact, it's my understanding that you actually loose power off a header on a street A series. You would need much more power out of the engine to justify a header. 1.75'' exhaust is the best size for your engine.

 

I'll let GGzilla chime in here. He's an a-series guru :P

[ggzilla]

Well first let me warn you that guys here are against those specific headers (from Bill's Datsun Shoppe).

 

But in general you will get slightly more power and can get better fuel economy with the tubular headers. But you will need to rejet the carb to get both. With the new 1.75" exhaust and headers, power should be good right off the bat.

* To restore the economy you could rejet. Just be sure to use a stock type temperature-controlled air cleaner to regulate input air temp, so the jetting can be consistent.

* Otherwise for power, jet it for "normal" cold air and fit a cold air intake. But then you gotta jet it richer to leave some fudge factor as the temp goes up & down.

 

1977 B210 already has the large engine. All USA B210s 1975-1978 were fitted with only the A14 engine. However if your's is a factory 5-speed car, you have the low-po A14. It is designed to maximize low-RPM horsepower and 1977 tuned for maximum fuel economy (50 mpg FED, 47 mpg CALIFORNIA model). Changing the exhaust or carb is going to lower your economy -- a lot. Only very careful tuning (by an expert) will restore it. I would keep that one stock. If you don't get the rated economy at 55mph, adjust everything to spec and calibrate your speedo. Your underhood ID plate should say: 65 HP lo-po, 80 HP hi-po.

 

If you have an original 4-speed engine, that's the hi-po A14, good for max power at 6000 RPM. It has a different cylinder head which a Weber 32/36 will wake up a bit over 4,000 RPM. When accelerating, keep it revved up after 3000 rpm, drive it an extra gear lower than normal. Rev the snot out of it and you will appreciate the Weber. Otherwise the Weber won't matter.

 

Now, most guy just like the sound of a header. It is noiser than stock, but in an interesting way. That alone may be worth it to you. For that reason, I don't use a header in my daily driver A12, but I have one in my weekend A14 Truck.

[Mini-L320]

I just changed over to a header on my A15. The only way you can positively know for sure that your either loosing or gaining any Bit of power is to go bring it to a shop and get it Dynoed.

 

And yes they make quite alot of noise if you have Open Header Like I do, Hehe :D

 

Notice how I said Header not "Headers"?

[Ozomatli]

Thanks for the help!!,

My car does have an A14 engine and the max hp. shown on the plate is 78hp

and i got the transmission from a b210 hatchback from 1976 one year before mine, and it has the dogleg pattern, just to give you an idea.

According to what you advice i should keep the stock manifold,I was thinking of replacing it because its loose or something, and because its making a strange noise,ill just fix it instead.

[ggzilla]

Intake manifolds don't make noise. But it will look much better if you replace it with a sidedraft manifold and sidedraft carburetor. Buy a CARB-legal kit from redlineweber.com

[Ozomatli]

Intake manifolds don't make noise. But it will look much better if you replace it with a sidedraft manifold and sidedraft carburetor. Buy a CARB-legal kit from redlineweber.com

 

Hi again, would i need to move the brake master cylinder to be able to put a side draft carburetor? and whats the benefit of a traditional carb, to a sidedraft one?

 

Thanks again for the knowledge!

[bonvo]

your in cali if you ever wish to make the car legally pass smog leave everything stock

[Ozomatli]

your in cali if you ever wish to make the car legally pass smog leave everything stock

 

Thanks for the heads- up but, I have not had to pass smog for some years now. I believe the only problem would be if i got stopped and someone checked, right?

[ToastyBass]

I know this thread's a bit old, but I'm bord this morning. XD

I've been researching a twin-sidedraft setup as well!

The best I can find is on an ancient thread written by blownb310 found here:

 

Sidedrafts are nice because they're a synchronized system using multiple throttle plates, up to one per cylinder. This helps with throttle response like on a sport bike. I personally love the ease of setting changes you can make with the DCOE, not to mention their simplicity and vast pool of resources and how-to's.

 

As far as mounting the things, you're right. The master cylinder will need to be moved over almost behind the driver's front strut tower. Compatible parts for this are a brake master cylinder from a Sentra (B11?) up to 1986 (I found the right type under '85 on RockAuto) and a clutch pedal from a B13. A lil cutting and drilling on the bulkhead and it should fit nicely. I haven't done all this yet as my Hitachi 2bbl still works fine, but I plan to in the near-ish future.