Last week I purchased and had installed some header which most won't be familiar with, but are worth looking at. Forced Fed sells headers for the 350z and G35 which are very similar in design to the $2500 Veilside headers, but only run $499. Here's a link to the product: http://www.forcedfed.com/350z/headers/F2350zheader.html

The reason I chose these particular ones over others is that I had a chance to see product in person before I purchased them. They are a fantastic quality for the price. All stainless steel, very clean TIG welding, thick header flange, all flashings inside the flange and collector areas are ground down and rough smoothed. They also use a better collector design than others in the price range, such as Stillen and DC Sports. Rather than use a general 3-1 collector and then stick the pipes in, each of the exhaust pipes is cut to fit the pipes next to it and then welded together.

The installation only took the mechanic about 4 hours (no lifting or removing of the engine required), so the labor was only around $300. With taxes, everything came out to be about $850 out the door. And for those sedan owners wondering, I have an AT sedan, so yes they DO fit the sedan without any issues.

The sound is a little bit louder, but nowhere near as much as most aftermarket exhausts will make it. It gave me the slight agressiveness in sound that I was looking for. Paired with the coupe mid-pipe, it gave me the exhaust sound I was looking for. Not loud for day-to-day use, but mean when you get on it.

Performance-wise, I'm always sceptical, especially when installing something that adds more sound to the car. Invariably a loud exhaust note will always "seem" to give a performance gain. So rather than say I felt an increase in performance, I had the car dyno'd. Since the last time my car had been run on the dyno (same dyno, same shop), I'd only added a coupe mid-pipe (probably only worth 1-2 hp, if any), heavier/wider 18" wheels (I had non-sport 17's before, so that will affect the dyno numbers negatively), and of course the headers. I was quite happy to get gains across the board, with a 8 hp gain and 6 lb ft of torque at the peaks. I'm guessing if I'd changed back to stock mid-pipe and wheels/tires, it would have been good for about 10-15 hp for just the headers alone. (I have the before and after dyno run files, but don't know how to convert it to a picture file, then post it. Sorry.)

Overall I'm very pleased and would recommend them to anyone interested in getting some quality mid-priced headers that will fit all models of Z and G35 (with the exception, possibly, of the G35x). I think paying the extra money for stainless steel and solid built headers is worth it over paying $150-250 for headers of lesser quality. Having the peace of mind that you won't develop a header leak or a cracked header weld down the line is worth the extra money.

All of this, of course, is just my opinion....

Thanks for reading!

 

Are your run files .drf files(used by winpep)? If so, zip them up and post them here and I'll export the graphs for you if you'd like.

 

Headers look nice.. welds are nop notch

 

The runners appear to make no attempt to be equal length, and there is no collector. All the pipes seem welded together just before the flange. I'm no expert by any means, but this seems contrary to good header design. I'm glad your happy with them, and you feel, and the dyno showed gains. Good Luck.

Lou

 

With the exception of Crawford, non of the other headers are truly equal length. Regardless of twists in the pipe which may give the appearance of equal lengths, they really aren't. The pictures on that website don't do the collector area justice. The inside of the collector is cleaner looking in design that you would think. All of the pipes come together perfectly. Comparing it against other companies who run the pipes into a 3-1 collector pipe, I think the Forced Fed headers have a surprisingly better collector area even though they are just a pipe into pipe design. I'll try and stop by the place that sold them to me and get a picture of the inside of the collector area.

 

4DrSkyline,
I have three graphs, and an excel spreadsheet that contains a little analysis of your runs. On average, you gained 6.59hp, and 6.88fl-lbs of torque. You netted a minimum of 1.35/2.02, and a maximum of 13.15/13.03. The torque gains were modest, until a range from 4200-4700, then they picked back up at 5300(a gain of 13ft-lbs).

Now, I have a question. Were both runs performed in the same gear? Or what about the same wheels/tires? The post-install run showed a gear ratio roughly 4% shorter than the pre-install run. That will impact your numbers.

The first graph is your pre-install run. The second graph is the post-install run. The last graph is the two runs overlayed.

 

And here's the xml analysis file. The file is zipped because driver doesn't allow attachments with the .xls extension.

 

Damn Trey, you did a great job in analyzing the data! Many thanks for posting the images too.

I went from stock non-sport sedan wheels and tires (215/55/17) to and 18" wheel and tire combination that was 4 lbs heavier per wheel and tire (245/45/18). If I recall correctly the wheel/tire combo was 50lbs for the stock ones, and 54.5 lbs for the aftermarkets. Both the pre-header and post-header runs were done in 3rd gear (I have an auto trans).

 

can we get some pics of the collectors

 

And the collector diameter?

 

Sorry for the delays in getting more pictures for you. I go by the shop that sells them pretty frequently, but it's never with my camera. I'll try to remember next time I go by there.

 

Your headers mirror the Fujitsubo, Esprit, and Unlimitedtuning design as well. Thanks for the review and dyno charts. I'd love to see a pic of the inside collector as well. Glad you like the headers. They look very different.

 

update of the header after a tune?

 

Are Stillen's Mandrel bent headers equal length?... they claim to be.

 

I think in reality, only Crawford has true equal length headers. All others appear to be unequal. On the dyno, though, it appears that you can make nearly as much power with aftermarket unequal lenght headers. The difference in price and added installation costs don't seem worth it to me.