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Discussion Starter · #1 ·
In JC Whitney, Pace Setter makes a header for the zcars and I was wondering if any one knew if they where better than the headers from MotorSport.
Also I was wondering if building up a 82 zx motor was cheaper than a V8.(Starting from the block up).

Just wondering.

Thanks for any info,

Rudy
 

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> In JC Whitney, Pace Setter makes a header
> for the zcars and I was wondering if any one
> knew if they where better than the headers
> from MotorSport.
> Also I was wondering if building
> up a 82 zx motor was cheaper than a
> V8.(Starting from the block up).

> Just wondering.

> Thanks for any info,

> Rudy

Do yourself a favor if you are going to buy a new header, get the Nissan Motorsport header, you'll love it, it's much MUCH better than anything on the market. I'd also consider the Monza brand that Victora British sells or the Arizona Zcar header next.
One thing that some folks overlook or ignore when adding a V8 to a Z is it needs to have a lot of added bracing welded to the car to take the torque the V8 adds or you will have a Zcar that won't last too long. Even the folks that build the stock motors to high HP have to modify the frame/body, it's not that rigid so that cost should be factored in if you want the car to last. Also (a personal consideration) if I ever did think of puting a V8 into a Z I consider alum. heads a requirement to get as much weight off of the motor and that's another 1000 to 1500 expense but those heads are something for adding performance as they have a much better chanber shape and port flow, they add at least 30hp min. depending on what brand you get and can go much higher than that.
Check out the Nissan headers though, get a catolog if you don't have one, and it's a good idea to spend a bit more to have them coated also.
 

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Re: More than meets the eye

There are several things to consider here. One, it will most certainly cost more to put a V8 in your Z. don't look at just the cost of the motor and trans, consider the mounts, time, effort, etc.. and expect to spend 4-5k at least to put a v8 in your Z. Now, as for headers. I agree that the Nissan Motorsports in the best header, but it is 300 by itself, and coating is another 195. Since you are refering to the JC whitney catalog, and by the comments you make, I will assume that you are on a budget. First you need to consider what you are doing to the motor overall. If you are not putting a cam in it, maybe port matching, then a header will yield you nothing more than noise. It will yield a hp or two at best over a stock 280 manifold,(tests have been done, and are on zhome.com, under the hp section). You have to look at the overall picture. If you are leaving the motor mostly stock, you will see the best increase from adding a good quality exhaust system that starts from your existing manifold back. That is what gains power, not the header itself. A good 2 1/2 inch system,(some will say 2 1/4, but unless you have mandrel bends, ie no crimps, go with the 2.5). if you did that, and kept your stock manifold, you will be happy. But if you are looking at a new camshaft as well,(I recommend a mild cam), then a header will benefit as well.
-Bob Hanvey
 

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Re: More than meets the eye

It would have been nice if those graphs were a bit in higher resolution but they still get to the point of using headers no matter what the setup. If the headers are tuned with a stock engine you won't see much of any final HP gain and that's not what I'd look for anyway. I'd be looking for a slightly sharper curve (say 140hp at 2500 vrs 145hp with tuned header). You don't see a higher HP at the cam's limit but you do see higher HP throughout the HP curve and this is where the increase in gas mileage is seen. Now I'd like to see how a coated header would fair on these graphs also. I'd also like to see how a motorsport junk 6-2 header would fair as a non tuned header can be worse than stock. Anyway, who runs a stock Z these days. According to almost every book on them the stock cam is junk and you get a lot better power/gasmileage with a mild cam than you do with the stock one, I saw a good increase using a .460 270 duration than with stock, this is my favorite street cam and works very well with the dual weber DGV's. When I finish getting the exaust coated I hope to find a difference but I also think it would be better to coat the whole exaust to the muffler, seems silly just to do the header and have the gas condence and slow down in the rest of the pipe. That's just a guess though but who know......
 

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Re: Header coatings and more

> It would have been nice if those graphs were
> a bit in higher resolution but they still
> get to the point of using headers no matter
> what the setup.

Ok, I was talking about a different set of tests, but those were similar. My point was 3-500 dollars is not justified for 1-5 hp, and that is in a best case scenario. I happen to run the Nissan Motorsports headers on my car, but mine is far from stock, and it most certainly makes a difference in my car.

I'd be looking for a
> slightly sharper curve (say 140hp at 2500
> vrs 145hp with tuned header). You don't see
> a higher HP at the cam's limit but you do
> see higher HP throughout the HP curve and
> this is where the increase in gas mileage is
> seen.

I am not sure where you are coming from. Are you saying that a cam will not increase hp? It most certainly will. And it is not the increase in hp that increases your mileage. It is the design of the Datsun head, and how a mild cam really lets it breath better, yielding better efficiency. Of course, you reach a point where that starts diminishing again, which you are right on the edge where it starts back down.

Now I'd like to see how a coated
> header would fair on these graphs also. I'd
> also like to see how a motorsport junk 6-2
> header would fair as a non tuned header can
> be worse than stock. Anyway, who runs a
> stock Z these days.

Actually, lots run what I would call a Near stock configuration. Most people don't want to get involved with a cam swap, etc... And as for coated headers increasing hp, hogwash. There is no such animal. It serves two purposes. One, it acts like header wrap, decreasing temps around the engine,(by transporting it down the pipes - which doesn't yield any noticable increase in power), and by protecting the header from rust, etc...

According to almost
> every book on them the stock cam is junk and
> you get a lot better power/gasmileage with a
> mild cam than you do with the stock one, I
> saw a good increase using a .460 270
> duration than with stock, this is my
> favorite street cam and works very well with
> the dual weber DGV's.

Yes, a mild cam does increase mileage, power, etc... but the stock cam is not junk. It is just not optimized for all out power. Remember, it was designed for every user in mind, not the one who always put the good gas, etc.. in.

When I finish getting
> the exaust coated I hope to find a
> difference but I also think it would be
> better to coat the whole exaust to the
> muffler, seems silly just to do the header
> and have the gas condence and slow down in
> the rest of the pipe. That's just a guess
> though but who know......

This is not what happens. The gas will never condense. There is an advantage to it cooling down as it runs through the exhaust, it takes up less space, thus can slow down a little, and bends and such aren't such an impediment.
Let me finish by saying I am not attacking your views,(for in reviewing my stuff, it might come off that way), but just making sure the air is clear. There is a lot of misconceptions out there.
-Bob Hanvey
 

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Re: Header coatings and more

Well I guess I better respond to this one or I'll never come back, might not anyway.
As tuned headers work by my understanding by design of tube lenght and width it sets up a resonance that helps each cyl. by adding a pulling effect which helps clean out unburned gas along with the piston, just a added hand so to speak.
By the scavaging effect of a tuned header the benefits are less unburned waste so what gas is pulled in burnes better giving more power.
More power per cyl for the same amount of gas equals more gas mileage.
As far as header coating not helping, it just seems common sence to me, not the pink elephant next to me but just me so far.. hehe.. But when hot gas meets a cool surface it does condence, the air conditioner works that way also, this much is a fact but anyway, as it cools it looses energy and slows down and also effects the resonance the header/valves sets up and has a overall effect on not only the header itself but puts a brake on the overall flow of the gas as the more it cools the heavier it gets, it's changing it's state as it flows through from header to muffler.
This is my thoughts on the benefits of tuned headers and also a coated one but it would only really help to have to whole exaust done the same way. This isn't a scam that header sales have made up just to help sell coated headers, it's basic physics.
But that is enough, I've seen the results of changing from untuned to tuned headers in gas miles but have yet to coat a setup so I can only go by basic gas properites and thermal dynamics.
 
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