Which header would you use..?

[carpenter]

Hello,


...so, finally I started to buld new exhaust and I have question about header. I own two and not very sure which one would be better, one is a chinese copy of BTB, the other one is pretty rare e21 longtube Hartge header (longer tubes than e30 Hartge header). Engine is m20b25 at the moment, but I plan to build m20b28 or even m20b31..

Some people say Hartge is an outdated design in comparison to BTB3, but on hartge e21 broschures says it would bring 10HP on a 2,3 motor...which is not bad at all...


...sooo, which one would you pick?





or...:





Thanks...!

[MrBurgundy]

Hartge, because hartge

[digger]

hartge look skinnier and longer and the collector looks better than the knock offs so id probably use it provided it fits on an E30. then just run a Y or X merge about 850mm or 1700mm from the end of primaries if its a street car

[thatblacke30]

Hartge all the way. I've been thinking about getting one as well.

[squidmaster]

Hartge definitely. That ebay one is a mess. But in reality, almost anything is better than the stock M20 manifold

https://www.instagram.com/p/BOK0W-kAWHI/

[uturn]

Too bad you're not stateside or you could get in on the "Racing Dynamic" header group buy(shipping would probably make it not worthwhile.)

http://www.r3vlimited.com/board/showthread.php?t=237041

[carpenter]

Thank you all for answers. Hartge it is then. I will send it to ceramic coating. Im sure Racing dynamics is excellent but it wuld be expensive to get it here...

So, now I have headers and this catback:

http://www.ebay.de/itm/BMW-E30-320i-...Platform%3AE30

Pipes are straight thru 2x 45mm.

Thanks digger, for recomendation about the merge position, I´ve read your thread many times, a lot of very useful information :up:
1700mm from primaries means better torque below then?


So, now I have to build the middle part. I want to keep double pipes. So, if I will build a stroker in future probably better go 2x 50mm instead of 2x45mm?



Version 1:

I was thinking of going 50mm diameter from end of primaries on, then put two resonators in place where is now cat, then x-pype on 1700mm and then catback (2x45mm).
Problem here could be raspy sound? which I really dont like... if i would put a muffler 2in2out instead of resonators this means that gases will merge too soon probably?


Version 2:

2x50mm from primaries on, x-pype on 850mm, muffler 2in2out, catback 2x45mm. Probably better sound (deeper) and less torque below...


Opinions?



Thanks

[squidmaster]

There's very little different in merging the gasses after the downpipe than using two pipes all the way back. It depends more on sizing, bending, and restrictions.

A general equation for collector sizing is: c = P * [1+F(π/42)]
where:
c = collector diameter
F = number of firing cylinders
P = primary size
π = well, pi. 3.141592 and so-on and so-forth

I can't remember the exact sizing of the hartge but I think it has 38mm primaries? What size are the collectors?

The exhaust manifold has the largest impact on where your power bands are. Generally, anything after the manifold, you want the least restrictive system. Each resonator you add will reduce the higher notes in the exhaust, similarly using larger diameter mid-piping will accomplish a similar effect.

http://sssquid.com/v2/exhaust-back-pressure-myths-theories-and-facts/

http://sssquid.com/v2/collector-comparison-50mm-to-62-5mm75mm/

[digger]

Thank you all for answers. Hartge it is then. I will send it to ceramic coating. Im sure Racing dynamics is excellent but it wuld be expensive to get it here...

So, now I have headers and this catback:

http://www.ebay.de/itm/BMW-E30-320i-...Platform%3AE30

Pipes are straight thru 2x 45mm.

Thanks digger, for recomendation about the merge position, I´ve read your thread many times, a lot of very useful information :up:
1700mm from primaries means better torque below then?


So, now I have to build the middle part. I want to keep double pipes. So, if I will build a stroker in future probably better go 2x 50mm instead of 2x45mm?



Version 1:

I was thinking of going 50mm diameter from end of primaries on, then put two resonators in place where is now cat, then x-pype on 1700mm and then catback (2x45mm).
Problem here could be raspy sound? which I really dont like... if i would put a muffler 2in2out instead of resonators this means that gases will merge too soon probably?


Version 2:

2x50mm from primaries on, x-pype on 850mm, muffler 2in2out, catback 2x45mm. Probably better sound (deeper) and less torque below...


Opinions?



Thanks

I don't think you'll notice much difference between 850 or 1700 unless you have More overlap than stock like 284 cam or above as the valve lift during overlap is not big enough to cause any noticeable downsides when the pressure waves are not working correctly

[carpenter]

There's very little different in merging the gasses after the downpipe than using two pipes all the way back. It depends more on sizing, bending, and restrictions.

A general equation for collector sizing is: c = P * [1+F(π/42)]
where:
c = collector diameter
F = number of firing cylinders
P = primary size
π = well, pi. 3.141592 and so-on and so-forth

I can't remember the exact sizing of the hartge but I think it has 38mm primaries? What size are the collectors?

The exhaust manifold has the largest impact on where your power bands are. Generally, anything after the manifold, you want the least restrictive system. Each resonator you add will reduce the higher notes in the exhaust, similarly using larger diameter mid-piping will accomplish a similar effect.

http://sssquid.com/v2/exhaust-back-pressure-myths-theories-and-facts/

http://sssquid.com/v2/collector-comp...to-62-5mm75mm/

Interesting reading :)

Just did some measuring.

Primaries: 38mm
Collectors: 42mm
Tube length from head flange to end of collectors approx: 75cm


So, according to your equation ideal size of collectors would be( i used 3cyl in the equation since I will use 2 pipes, right?):


c=38*(1+3*(3,14/42))=46,5mm for each collector

So, according to your link 50mm will be too much?



@digger, car is a street car it most not be too loud, the stroker I will built will probably be m20b28 with RHD ITB and 284/272 cam... so somewhere about 240hp at the crank...

[e30m3s54turbo]

I would go Hartge or similar. The best ones from a Alpina B3 2.7 headers are bigger than Hartge.

[squidmaster]

I would recommend the closest size you can get to 46.5 for the first collector. Since the hartge ones are undersized for my equation (42mm) I'm hesitant to say the best secondary collector size as we really only are using the equation for the primary collectors. As far as exhaust after the downpipe/longtube manifold, it's better to go less restrictive in terms of pipe back pressure. The main concern in an exhaust system is making sure the gases exist the primaries-- moves away from the combustion chamber-- as efficiently as possible. And at the point of collecting into a single midpipe we now have exiting gases that are more spread out, and more frequent, making a kind of rolling wave effect, rather than harsh moments of high velocity and pressure followed by longer periods of blocked flow, such as in the primary collector.

[squidmaster]

The style exhaust you picked is generally a little raspy from what I've heard. If you're looking for a quiet exhaust the flowmaster turbo series are alright. Quiet, almost stock level, but still better flowing than most others of comparable decibels.

On the sportier side the Vibrant Stealth muffler is pretty nice. Resonators are key. If you want to safe you can add an inline muffler, something like the magnaflow 14419 works great.

[carpenter]

Well, sh*t. Today I tried to put hartges on the car-just to test fit. They do not fit. A I mentioned, they are for e21, but seller offcourse said they fit on e30 too.
The 2nd part-the one at the firewall, is just too wide. It hits the chassis on the right. I can get them on if I lift the engine for about 2 cm. So, they are about 1,5 cm too wide. The first part fits ok, but I cannot mount oil filter on flange for oil cooler, maybe smaller filter would fit..

Now I can:

-adapt the 2nd part, cut pipes for about 1,5cm at the flange and weld it back which can be done, but probably not good for flow (different length)
-mount the BTB copy with some improvements
-sell both of them and buy something else...

[squidmaster]

Yikes! I'm sorry I didn't notice that they were for the e21. I saw the hp gain mention but just through it was a reference. Might be an excuse to install an oil relocation kit? Maybe a better cooler if you plan to build the engine for track?