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I need some help. have a 82 alfa spider, is it a good idea to install headers, and what are the benifits.
Peppy
 

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I think you would be better of coating the stock manifold. This depends on what your aspirations will lead. The stock manifold works well.
 

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louder

I need some help. have a 82 alfa spider, is it a good idea to install headers, and what are the benefits.
Peppy
You can expect the noise level to increase slightly with a change from the stock manifold to a set of headers.
 

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they are less prone to cracking,, and for replacement cheaper, there are only so many good stock set( oem ) out there now
 

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Special headers are mainly for race cars.

Original headers work well for the street and are quieter. Coated to look like "iron" they radiate less heat and look good.

Had to use tubular headers in my 101s.
 

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Weren't the 82 manifolds from the more restrictive years of manifolds?
 

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Assuming that your engine is stock:
The major benefit is they look cool when you open the hood and show your friends. The major disadvantage is the amount of heat that they discharge, raising the temperature of stuff nearby including clutch and brake hydraulics, steering box and speedometer cable. The impact on performance depends depends upon whether you buy well designed ones or not so well designed ones. The former are likely to give you a few extra HP while the latter could cause you to lose power. But in either case the difference will be too small to notice.
Tubular headers are part of the recipe for a high output engine but they don't make much difference unless you make other modifications to your engine.
 

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Alfa exhaust manifolds are pretty well designed - the early (S2) 2 liter factory exhaust manifolds flow as well as most aftermarket headers. It seems odd to some of us who are used to American cars that cast iron manifolds can be as good as tube headers, but that's just another example of how thoughtfully Alfa engineered their cars
 

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Opinions about headers are all over the place. Personally, I think they help the most when you've done extensive modifications to the engine. Less so with a stock engine. Some later Alfas came with a one-piece header that was more restrictive than the earlier two-piece headers. It's very worthwhile to retrofit in that case. But you'll probably also have to change your exhaust system too. Two-piece headers are still relatively easy to find and reasonably cheap. If you can't find any put a post in the parts wanted forum and I'm sure someone will have a pair that just sitting around gathering dust.

Here's a very informative post re: headers from someone who really knows what he's talking about. Scroll down to George Willet's comments:

http://www.alfabb.com/bb/forums/gta-1965-1975/25952-gta-style-header-recommendations.html
 

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cast iron manifolds can be as good as tube headers
look at post # 117 of this thread http://www.alfabb.com/bb/forums/spider-1966-up/29640-msierts-black-spider-project.html

This is a highly modified motor which originally had the stock Alfa exhaust including the two piece S4 cast iron manifold that was replaced by tubular headers and a single straight through muffler. The power went up from 170 to 196 HP. They made some cam timing changes at the same time so the new exhaust cannot take full credit, but the stock, restrictive exhaust system cost them a lot of HP.
 

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Headers make sense only if replacing the entire exhaust system with a performance one, such as Magnaflow. Otherwise save your ducats for something more meaningful...
 

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Headers make sense only if replacing the entire exhaust system with a performance one, such as Magnaflow. Otherwise save your ducats for something more meaningful...

that's not strictly true. if the exhaust manifolds are badly done than there is a substantial gain to be had in changing them regardless of what the rest of the system looks like ( on any car ) . as example, my 79 had the iron smog manifold that was terrible and I changed out for the early stock cast " header" system and it woke the motor right up. if I hadn't been able to source an early set I would have done headers of some sort . on this later car that this guy has, I don't know what his stock iron manifold looks like or if its any good or not. if its bad like my 79 was then he will get some meaningful benefit doing something else. if its decent like the early cast headers and he does nothing else to the motor then headers will be a lot more trouble than they are worth as others have rightly observed.
 

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that's not strictly true. if the exhaust manifolds are badly done than there is a substantial gain to be had in changing them regardless of what the rest of the system looks like ( on any car ) . as example, my 79 had the iron smog manifold that was terrible and I changed out for the early stock cast " header" system and it woke the motor right up. if I hadn't been able to source an early set I would have done headers of some sort . on this later car that this guy has, I don't know what his stock iron manifold looks like or if its any good or not. if its bad like my 79 was then he will get some meaningful benefit doing something else. if its decent like the early cast headers and he does nothing else to the motor then headers will be a lot more trouble than they are worth as others have rightly observed.
In the state of Kommiefornia, modifying emmissions system including exhaust will likely garnish a "fail" at the next smog inspection. Hence I have only considered doing these type of mods on my pre-76 cars ( cut off YM for smog exemption). Some have resorted to installing earlier S2 OE manifolds on cars subject to smog to gain few hp and some bottom torque without tipping off authorities. Again, without making serious mods to the engine (incl chucking the emmissions mumbo jumbo) and the rest of the exhaust, earlier OE manifolds would be a better option - cheaper and easier to install.
 

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Ed, what RPM was the peak HP at?
HP peak at 7300, torque peak at 5700.
I have been inspired and influenced by this project but my motor is not built to survive at such high rpm. Stevesxm in particular advised me that the 2.5" system used in Murray's car was designed for high rpm power and as a result my new system is 2.25". That is the same diameter used by Alfaholics in their system and the same that Steve used on his championship winning formula Ford racers. I will not know for sure where my peak power is until I get back to the dyno but I expect that it will be around 6500.
 

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I just swapped in a 78/79 4-2-1 system (same as Bosch manifold with air injection) on a 76 Spider that should have had a 4-1. With everything installed and nicely patinaed, air pump and injectors, plus a cat, the inspector had no idea it was not stock. And the numbers were incredibly low due to the cat. So some fudging is possible in CA, but it's probably got to be roughly similar to what the car came with, and the official reaction may vary depending on the inspector's knowledge.
Andrew
 

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On December 5th 1933, the US ended prohibition.

On January 1st, British Columbia ends emission testing of cars and pickup trucks.

:thumbup::thumbup:
 

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HP peak at 7300, torque peak at 5700.
I have been inspired and influenced by this project but my motor is not built to survive at such high rpm. Stevesxm in particular advised me that the 2.5" system used in Murray's car was designed for high rpm power and as a result my new system is 2.25". That is the same diameter used by Alfaholics in their system and the same that Steve used on his championship winning formula Ford racers. I will not know for sure where my peak power is until I get back to the dyno but I expect that it will be around 6500.
just for clarity ... the data came from the sports 2000 cars ( 2l ohc motors ) and other 2l motors in various trim from 150 to 190 hp . not the formula ford 1600 cc pushrod motors that made much less and used a 2" pipe.
 

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I have one of those $300 header on mine. Ceramic coated the inside myself with a rattle can from Eastwood and titanium wrapped it. No real heat problem. The Cat ends up where the resonator was and I use a stock muffler. Liked the way it sounds and the engine drivability is better. Can tell it has a few more ponies, but just.

I caught some flack from BBers that the CAT was too far back, but the ceramic coating titanium wrap kept the heat in and at emission time came back with zero emissions.

I say go for it!
 
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