I currently have a stock 2.0L with SSIs and Bursch with Turbo muffler.
With the engine in stock trim will I find any noticeable power differences with Kerry Hunter headers or similar.
Is a bone stock 2.0L going to see any appreciable increases in power by changing exhaust.
If I do go to headers, will changing to a less restrictive aircleaner help power.
I thought I had read somewhere that headers on a stock engine actually reduce power at certain rpms.

All right have at it.

The stainless heat exchangers are better flowing than stock as i recall they have a larger inside diameter, they also weigh considerably less. The Bursch exahust system is well liked by many 914 owners, it is a nice set up.

I do not have direct experiens with aftermarket headers, however usually changes in the exhuast or intake manifold will alter the torque curve to some degree. I suggest that you contact High Peformance House(HPH) and ask what they have and how it will effect your engine. Rich at HPH is very knowledgeable, and won't sell you junk, nor parts you don't really need, so go ask them.

Many times, with different exhausts, the cars sound is changed, a more racy exhaust tone will sometimes give the driver the impression of a big power increase, when in actuallity none may exist, so be aware of that.

You seem to have a pretty good exhaust system now, and i doubt you will have much gain if any if you change nothing else. The Bursch has a pleasant racy sound to it already.

putting an extentsion on the air cleaner intake "horn" to take cooler air from higher up in the engine bay was reported to improve engine performance, I read that on this web site some time ago, and it makes sense as cooler intake air will be denser, and thus will improve performance, noticable, well probebly not in day to day mellow driving, but maybe noticable if you race it around a bit. Many cars have cool air intake extension, regardless of make or model. this should be a cheap and easy thing to try out, use some of the aluminum flex hose (like the heater blower hose, found at many VW stores) and hose clamp it to the intake horn, and secure the other end up high in the engine bay near the grill, this will allow cooler air to enter the engine.

With out other modifications, such as bigger valves, porting, (which would likely require removal of the stock FI system) you probably won't see much increase just by adding headers.

Is your 2 liter a early or late one? high compression of low compression pistons?

There is only so much you can do to improve the exhaust before other things limit further power improvements. those other things tend to cost bucks. you already have an upgrade with the stainless heat exchangers, and Bursch. I do not know if you will gain very much more by only adding headers, the gain is likely not worth the expense (and loss of the heater ) But go ahead and build your self a cool air inlet, cost is a few bucks, and you should in theory gain some power from that.

Go much further, and some serious engine mods are required.

Generally a freeer flowing exhaust will make the peak torque at a higher rpm. Depending on the gearing,a nd type of driving you do, this may or may not be benificial

others please chime in on this, as I am not an expert on this subject, (Thats why i suggest you talk with Rich at HPH)

best of luck

Grassroots did a comparison a few years back on a 2.0,

in order of performance :

stock,
Kerry hunter header
Tangerine Racing Header

Personally, I'd go with a Tangerine Header* if it fits in your budget (I asked my wife this morning if I could buy one and she laughed at me...I wore my Tangerine Racing T-shirt today, damn did I look good, hahaha)

Next would be a European Racing header** with turbo/street muffler...this is what I am running right now as well as a few other local /4 guys.

*about a $1000
**about $500 if ceramic coated (recommended)

You lose heat, but you also lose something like 20 pounds or so compared to a stock system.

Only way I see losing power with headers is if you went way too small (not going to happen with current headers out there and your motor) or going way too big, which only Tangerine offers larger diameter headers and I'm sure Chris would recommend his normal setup.

Hi Mike:

were the stainless steel aftermarket heat exchangers tested with the others?


roughly what was the change in power and torque in the tests? and which engine was the test made on?

I want to get an idea of the gain for cost.

QUOTE (dmenche914 @ Aug 27 2005, 11:36 PM)

Hi Mike: were the stainless steel aftermarket heat exchangers tested with the others? roughly what was the change in power and torque in the tests? and which engine was the test made on? I want to get an idea of the gain for cost.

Hey Dave,

I cannot remember if the SSI's were tested or not, I "want" to say yes 'cause I thought they mentioned the SSI's being lighter than the stock steel H/E's. The H/E's were tested with a stock 2.0 muffler.

Motor was pretty much a stock 2.0, maybe a different cam, but nothing too radical since it still had the D-Jet.

don't qoute me
~5hp gain for KH header
~8-9HP gain with Tangerine

according to the article and Chris, his would have seen better numbers on a more modifed engine

as to cost effective, I think it's relative to what your goals are...for most people just driving on the street, laying down $500 for 5hp might not be very cost effective

Dan,

What you need to find out is how many competitive people in BP are still running heat exchangers. I'm srue there are few, but since the rules allow headers, most change to them to maximize thier car.

Go with the headers. The SSIs are larger diameter than the stock HEs, but their design is still the same. Real headers have a decent collector (not "just dump it all into the muffler" like stock), have equal lengths on the exhaust path, and so on. And remember, the exhaust side is where our motors need the most help. Get a Tangerine Racing header if you can afford it, or a K-H one if not.

--DD

Are new SSIs still available anywhere? PP says they are NLA.

Triad still advertises them.

It would be ineteresting to see whhere the Eurorace or Triad headers fit with the other headers.

Unfortunately, they didn't make the Grassroots header test.

I have the SSI/Bursch combo as well as the Eurorace with a coupla exhausts. Not sure which to use.

Ken

QUOTE (Dave_Darling @ Aug 28 2005, 06:30 AM)

Go with the headers. The SSIs are larger diameter than the stock HEs, but their design is still the same. Real headers have a decent collector (not "just dump it all into the muffler" like stock), have equal lengths on the exhaust path, and so on. And remember, the exhaust side is where our motors need the most help. Get a Tangerine Racing header if you can afford it, or a K-H one if not. --DD

unless the KH headers now have stub pipes, I'd avoid them and get a setup that does........

Thanks for the info Mike, I didn't relize that much gain could be made, 5 HP is more than 5% increase over stock. I guess the question the original poster had was with a stock engine. if the cam is modified, that might help the headers in a synergetic way???

You are right however, for the money and loss of heater, that may not be everyones cup of tea, depends on budget, and how you like to drive.

I mut say I am happy with my set up with stainless heat exchangers, Bursch muffler,a dn stock 74 2l engine, . Still waiting to drive it again, been on jackstands near two years now for that simple clutch job, that become an engine upgrade, then my hand injury. Had some buddies over last weekend, and they got the motor in, but we forgot (I forgot) to about one piece of sheet metal (the one in front) so the engine needs to drop again (UGH!!!) It was one of those weeks. They might be able to help me with the engine this coming week i hope. Sure miss that car. And hate being useless to fix it.



anyrate thanks for the info.

dave

For the Grassroots tests the "Stock" system was with SSIs. The engine had Euro pistons and some headwork.
The Bursch actually lost hp in the range above 5k rpm. The Tangerine picked up about 7hp near peak output while the KHH picked up about 5hp near peak.
The biggest difference was in the 3-4k rpm midrange where the Tangerine gained about 5-7hp over stock which amounted to a 7-10 percent increase. The KHH and Bursch gained only 1-3% in the same rpm range.
The Tangerine Header also yielded a flatter AFR across the full rpm range compared to the other systems tested.

- -

nevermind.

So with euro pistons and head work the headers mabe a difference over the stainless steel exchangers per the comments on this post. I guess that still leave the original question open, what advantage to a stock 2 liter engine (ie USA version pistons, stock heads, no porting0 My assumption would be that the the headers would have less positive effect in this case than the other.

i would rarely rev my 914 past 5000 rpm, so i wonder the extent of improvement at the lower rpms if any with the modified engine, and also with the stock engine with headers attached.

still don't recall what year model we are talking about, the last 2 liters (75/76) had some differences that gave them less power than the early ones.

what will be your application and driving style? What ads power to a prep'd engine that runs at the higher rpm scale may not help much at all on a bone stock engine driven at more conservative rpms. Again, i suggest you ask HPH for advice, as they do everthing from stock little ole lady drivers, to full all out race 914's. tell them what you got, how you want to drive it, and then get prices and see if that is what you want.

good luck on your choice, let us know what you decide

On a stock 914, the good headers (Tangerine, Eurorace, KH) should still make a noticeable difference. There should be some improvement at just about all RPMs, at least with the Tangerine one. I believe it never made less power than the SSIs, at any RPM.

All SSIs are of the pre-75 style--no 75-76 exhaust to worry about if we're talking about SSIs, as the original question was.

My own thoughts--

If you want to really be competitive, get the Tangerine Racing headers. Period, end of story. (OK, you still have to figure out which muffler to use and if you want the small heat exchanger wrapping, if the latter is available on 914 headers.) Forget the rest, the Tangerine one is better.

If the budget is the primary concern, then use whatever is on the car now. Just go out there and drive. Have fun, tighten up the loose nut behind the wheel, and don't worry about those extra few ponies. If you can beat people without them, that's an even better feeling than if you have them!!

--DD

I am not that worried about the minimal amount of HP gains. for now I will stay with my SSIs and work on the exhaust system I have a rear portion of the exhaust that exits in the middle with a flange so I am thinking about running a stinger with baffles in it for some tracks and mostly open at others like Th and Bw.
The exhaust I have available looks a lot like a system off of a Bug. Flange exits pipes in the dead center.
Center mounted stinger should fit the bill. I can also fab up a turbo muffler to exit in the stock location with this setup. I think Sebring or some such has a similar set up, unlike the Bursch that has a collector aimed to the side instead towards the rear. Also the Bursch has a welded collector instead of a flange for exchanging muffler types.
I will wait and see.
A good friend of mine just bought a 914-6 conversion with a 2.2 motor. Along with the car also comes a 2.0L-6 a 2.2E and a 2.7S motor. I may be getting the 2 or 2.2 for my car in the not too distant future.

I won't even tell you how much he paid since it is absolutely ridiculously low. Comes with a nice trailer, two sets of wheels, 2 spare trannys, and a whole bunch of other spares like 914-6 front and rear brakes and control arms.
All along with the car that is completely street legal and set up for TT, with all the suspension goodies, running a 2.2S motor.

I had a shot at it but passed to continue the build of my current 2.0L 4.