posted on January 21, 2014 13:31
350Z - Boosting Power With DC Sports and Berk Technology
So in the past installments of Project 350Z, we took a look at getting the car's suspension and brakes up to snuff. With the car handling and stopping well, we turned our focus to freeing up more power. Since the car is mostly a budget track day beater, we decided against forced induction options for now because making a high power forced induction motor reliable under continual hot lapping conditions is a somewhat expensive proposition.
To make a car that was not originally designed to be forced induction track reliable would require big changes to the car's oil and water cooling systems and modifications to the lubrication system all of which end up being expensive and adding complexity to the car. Big power in the Z33 chassis usually makes adding a diff cooler mandatory as well on a car with a mechanical LSD for anything more than just a few laps. On an early VQ35DE, forced induction track reliable power will usually mean building the bottom end to upgrade the pistons rods, bearings, cylinder head water circulation and head gaskets. Bigger power might also mean bigger tires, bigger brakes etc.
So to keep a decent budget balance, we decided to focus on some good bolt ons to see what we could get from our Z. For our first step we decided to free up the exhaust side of things with headers and an exhaust from DC Sports and free flow cats from Berk Technology.
We chose DC Sports headers because we wanted a modular system that would allow us to bolt any piece of the stock exhaust back in place. Yes we know that long tube headers might make a little more power but we wanted the flexibility to run stock cats if we had to later. We feel that the DC Sports headers are some of the best off the shelf reasonably priced short tube headers for the Z on the market.
The DC Sport headers feature all 304 stainless steel construction. Stainless steel is worth the price differential because it doesn't rust and since stainless has half the thermal conductivity of mild steel, keeps the heat out of the engine compartment and in the tubes for better scavenging and faster cat light off. A stainless header will make more power than a mild steel part of the same configuration.
The DC Sports headers have nice construction quality. Look at the CNC cut stainless flange. It is scalloped for less weight and to reduce the chances of warpage or cracking due to thermal expansion.
The headers have nice workmanship for a moderately priced mass production part, flashing is all hand ground away from tubing junctures and the welding consists of nice TIG welds.
Wednesday, January 22, 2014 10:19 AM
Another good mod is to use a plenum spacer. The 350Z suffers from air restrictions in the front cylinders due to the upper plenum design. Several companies offer a solution for this.
I'm surprised that you said this exhaust wasn't loud. Perhaps it's the cats and full dual exhaust. Many people remove the cats with headers and the Z gets really loud. I might have to consider replacing my Nismo exhaust at some point with something like this.
Wednesday, January 22, 2014 10:40 AM
@jeffball - you are one step ahead of us with the spacer. Stay tuned!
Wednesday, January 22, 2014 1:43 PM
Holy cow, that rear diff has a HUGE heat sink on it.
Wednesday, January 22, 2014 2:18 PM
It is a Nissan Motorsports diff cover from a euro model Z. The 350 has a diff heating problem.
Wednesday, January 22, 2014 4:55 PM
man... 350Z parts got a lot better... When I had mine all bolt on's were next to useless for actaully adding any power...
what else you do plan on adding to get another 20 out of it?
Wednesday, January 22, 2014 5:34 PM
Wow, huge gains. Must have a very adaptable ECU.
Looks like the swaybar and exhaust might knock on bumps? Small price to pay for almost 20hp!
If i could suggest something general; it would be nice to have page number buttons at the bottom of an article to be able to flip from page to page quicker to look a specific pictures or dyno results without having to flip all the way back or ahead again.
Wednesday, January 22, 2014 9:08 PM
I'd love to hear what it sounds like, do you have a video?
Wednesday, January 22, 2014 10:05 PM
I understand that every engine has a different “optimum” runner length (which in itself may be different depending on the intended use of the engine), but I have a general question about exhaust manifolds on V-engines: Is it feasible (or even worthwhile) to make the runners long enough to tune all cylinders together? Otherwise, like in the case of this vehicle’s V-6, it seems to me that the manifolds are optimized for two separate three cylinder engines, then merged 4-5 feet from the exhaust ports (at the Y-section merge). “Reverse flow” engines (intakes on the outside, exhausts in the valley) can have very effectively tuned exhaust manifolds regardless of the number of cylinders or firing order. How much power and efficiency are we losing, if any, when designing/manufacturing exhaust manifolds for V-engines that don’t have the two banks merge until much further downstream?
Thursday, January 23, 2014 1:12 AM
What you say is true but it is very difficult to package such an exhaust within the constraints of a modern production car.
Thursday, January 23, 2014 3:51 AM
I'm a little disappointed that you didn't get before and after weights of everything.
Thursday, January 23, 2014 1:40 PM
@BANFSTC and Mike
There was a guy on my350z.com forum that made longtube headers for his car with great results. He was located somewhere in Canada and raced his Z in a series there. He was planning to make production headers but I don't know if he got around to that. If interested you can prolly find it on there.
Friday, January 24, 2014 8:40 AM
It's Sacha Anis from SG-Motosport. The sound for the long tube headers is amazing, close to an italian V12. SG-Motosport closed a couple years ago.
Friday, January 24, 2014 8:52 AM
It should be noted that Sacha Anis is still doing works on his 350z with LT headers (also with ITB and full of black magic) and is now over 400whp.
Friday, January 24, 2014 11:56 AM
Very nice work. 2 things I am wondering. 1, will this thing still pass emissions with the HFCs? And 2, how much power would this thing gain from a tune? I also wish you guys had dyno'd everything individually. Still though, a ~9% power gain through the rev range from just changing the exhaust is pretty damn good. I'm also surprised the header install went so painlessly for you guys; for folks without a lift I've heard it takes days. I want a set for my car but I think I will just pay to have them installed.
Friday, January 24, 2014 1:53 PM
As per the first caption of our story, we didn't want to do long tube headers, we wanted a modular exhaust system where we could bolt any part of the stock exhaust back in place.
Some of this system like nearly all performance parts is for racing use. With the high flow cats in place the car probably would pass a smog test but unless a part is CARB approved with an EO number it is not street approved no matter how clean the exhaust is.
Installing the exhaust was not super easy but not particularly hard. It took about a half day including taking time for taking pictures and dyno testing.