M20 Header Options in 2019

[vehicular]

I'm piecing together a 3.1 street motor for my E30 daily, and I'm having trouble finding M20 headers I consider worth spending money on. The combination will be 1mm over bore, M54B30 crank, moderate cam, mild ported head, MSPNP, likely ITBs eventually.

Has anybody used the Becker headers available on Ebay? The rest of the ebay E30 headers tend to be a mess, but these ones are 4 times the price, so they're 4 times as good right? Seriously, though, has anybody used them? Do they actually fit?

I'm hesitant to buy the IE long tubes being as they're mild steel with pressed connectors, will require an O2 bung welded in the exhaust or a collector, will either vbands or flanges welded in (or using band clamps over a coating, which kind of sucks over time)... If they were stainless, I would just buy them, but having to either use band clamps and move the O2 sensor down stream, or having to modify them, and then send them out again for coating kind of turns me off.

Supersprints are still available, but they're obscenely expensive. Same with the Racing Dynamics group buy, (plus I would either have to use the small OEM down pipes, or build something myself) (not that big of a deal, but for that kind of money...)

Am I missing any other options? I guess I could do the IE shorty headers. I'm hesitant to buy a short tube header if there are better options. I'd buy Stahls or similar if somebody had a nice used set, but I can't tell you the last time I saw any for sale.

[kronus]

if you want a bolt-in solution, you should get the supersprint exhaust. everything else will require fabrication, which is kind of expected from people who buy performance exhaust components anyway.

I am working on a 3.1 as well, and went with IE long tubes. I am planning on building exhaust back from them with slip flanges and stock-type mounting back to a stormung catback.

shorties are not substantially different from cast manifolds performance-wise.

Having struggled with M20 headers with separate flanges for each runner, a common flange was at the absolute top of my list of requirements. (header pulled out some exhaust studs, time-serting an installed M20 head trackside sucks)

[E30-TourZing]

I am building a 3.0L M20 and I have got a standalone tune planned as well. I to have a Stromung cat back exhaust going in, but I was fortunate to find a used Bavauto longtube header setup. I will need to thread a O2 bracket, but it's just part of the course.

I read alot about headers, and I can see why it's confusing to know what to buy. The price difference between the options are quite different. I have heard nothing but good things about Bav auto's headers, so when the opportunity to buy that setup came towards me, I took it. I believe I paid $250 for the headers and connecting pipes. I bought them over a year ago.

Perhaps you could put out a wtb listing, and remain hopeful. How far along in your project are you?

[vehicular]

if you want a bolt-in solution, you should get the supersprint exhaust. everything else will require fabrication, which is kind of expected from people who buy performance exhaust components anyway.

I am working on a 3.1 as well, and went with IE long tubes. I am planning on building exhaust back from them with slip flanges and stock-type mounting back to a stormung catback.

shorties are not substantially different from cast manifolds performance-wise.

Having struggled with M20 headers with separate flanges for each runner, a common flange was at the absolute top of my list of requirements. (header pulled out some exhaust studs, time-serting an installed M20 head trackside sucks)

A bolt in solution isn't necessary at all. I will almost certainly be building an exhaust from whatever headers I use back. My hang ups with the IE long tubes are 1.) putting slip joints and clamps over coated mild steel, which in my experience invariably leads to the coating wearing off over time and then leaks and corrosion between the slip sections, and 2.) spending that much money on a set of mild steel headers with pressed collectors that require finishing work and finding somebody to coat them (or putting Cerakote on them and refinishing them myself every couple years, I guess?).

People insist that shorty headers are no performance benefit over stock manifolds, but the stock manifolds are really bad from a performance best practices perspective, and I can't accept that there's not some gain to be had there. At least on a warmed up motor, if not on a stock one. Also, my manifolds are kind of crusty, and I'm not convinced I can get the nuts off the studs without breaking them.

I don't see how individual flanges per port would cause studs to be pulled out? They're a pain in the ass to get aligned sometimes, but I don't see that they would cause studs pulling out.

[kronus]

the headers naturally move and warp with heat. this applies pressure to the studs, and if a particular runner exceeds the stud's holding force in the (soft alloy) head, it pops out.

having a flange to keep them all in a row makes this not possible, since the flange is usually pretty thick and resistant to bending, and the only way a runner could pop that entire weld is if it was poorly done.

[kronus]

A bolt in solution isn't necessary at all. I will almost certainly be building an exhaust from whatever headers I use back. My hang ups with the IE long tubes are

1.) putting slip joints and clamps over coated mild steel, which in my experience invariably leads to the coating wearing off over time and then leaks and corrosion between the slip sections, and

2.) spending that much money on a set of mild steel headers with pressed collectors that require finishing work and finding somebody to coat them (or putting Cerakote on them and refinishing them myself every couple years, I guess?).

1 - use something else, then? there are many options for exhaust joints - v-bands, OE-style sprung 2-bolt flanges, OE-style 3-bolt flanges, just one bigass piece of pipe, etc

2 - they come raw because the expectation is that people need to modify them per application. not providing downpipe flanges and downpipe chunks is a cost-saving measure that also allows IE to cater to people who want to use a different style of flange from the one they would have provided.

I'll be spraying mine with high-temp paint.

[vehicular]

1 - use something else, then? there are many options for exhaust joints - v-bands, OE-style sprung 2-bolt flanges, OE-style 3-bolt flanges, just one bigass piece of pipe, etc

2 - they come raw because the expectation is that people need to modify them per application. not providing downpipe flanges and downpipe chunks is a cost-saving measure that also allows IE to cater to people who want to use a different style of flange from the one they would have provided.

I'll be spraying mine with high-temp paint.

They can be ordered coated (it looks like Nitroplate, but could be something else), and I wouldn't want to screw that up with slip joints, or strip it off the collectors to weld flanges to it.

High temp paint doesn't last on tubular headers. I have used it before, and even following VHT's instructions to the letter, it will still peel within weeks at best. Cerakote works ok, and is pretty easy to spray in a garage with HF tools, but even it won't last more than a year at best, dailying the car in the southeast with no salt exposure at all.

[vehicular]

I am building a 3.0L M20 and I have got a standalone tune planned as well. I to have a Stromung cat back exhaust going in, but I was fortunate to find a used Bavauto longtube header setup. I will need to thread a O2 bracket, but it's just part of the course.

I read alot about headers, and I can see why it's confusing to know what to buy. The price difference between the options are quite different. I have heard nothing but good things about Bav auto's headers, so when the opportunity to buy that setup came towards me, I took it. I believe I paid $250 for the headers and connecting pipes. I bought them over a year ago.

Perhaps you could put out a wtb listing, and remain hopeful. How far along in your project are you?

I have most of it spec'd, but have only bought a spare motor to build, and the crank so far. I have an in with a piston manufacturer, and have had them build me custom pistons before, so I plan to use reconditioned S54 rods and have a set of pistons made to make everything work. I have access to a 3D scanner, so getting piston crowns made to quench correctly with the 885 head won't be an issue.

I have bought most of the parts to refresh/ restomod the suspension, so the motor will come after that... and maybe after some interior and cosmetic stuff.

The reason I'm looking at headers and exhaust now is that I have an exhaust leak from a rusty muffler that is driving me crazy, so headers and building an exhaust are on the list above actually rebuilding the motor. A set of Bavautos would sure enough fit the bill if I could find them. A WTB ad isn't a bad idea. I just never look at WTBs, so I never really think that other people might.

I have been planning on a build thread for a couple weeks, but have been travelling for work, and trying to finish putting a motor in my C5Z, and just haven't gotten to it yet. I'll try to get it done this week.

[SkiFree]

Given you are running a stroker engine, the old BavAuto header primaries are going to be severely undersized (@ 1 3/8"). Not to mention, they were also made from mild steel.

With all due respect, the IE's fit your bill better than any other option currently available. You just seem slightly abject to that reality. Lastly, have you checked to see if IE will weld on an 02 bung (or anything else for that matter)?

[kronus]

^^ IE has been out of long tubes for a while now. I had to find mine second hand.

[E30-TourZing]

Given you are running a stroker engine, the old BavAuto header primaries are going to be severely undersized (@ 1 3/8"). Not to mention, they were also made from mild steel.

With all due respect, the IE's fit your bill better than any other option currently available. You just seem slightly abject to that reality. Lastly, have you checked to see if IE will weld on an 02 bung (or anything else for that matter)?

I appreciate your testimony on the Bav auto headers. I am aware these have a smaller diameter then other options, but I didn't think the performance difference would be massively different.

I have super appreciated all the write-ups you have done about M20 strokers, and its very apparent your knowledge is vast. Have you personally seen results from a dyno/butt-dyno with 1 3/8 vs 1.5" on a 2.9-3.1 M20?

The reason I ask is due to the fact a close friend of mine is a master welder, and I feel we may custom make some stainless headers if the difference is significant enough. Parts coming to Canada are soooo expensive, so it's almost better to employ a metal artist then buy something ready made.

[vehicular]

Given you are running a stroker engine, the old BavAuto header primaries are going to be severely undersized (@ 1 3/8"). Not to mention, they were also made from mild steel.

With all due respect, the IE's fit your bill better than any other option currently available. You just seem slightly abject to that reality. Lastly, have you checked to see if IE will weld on an 02 bung (or anything else for that matter)?

You guys are probably right. I had a mild steel Boig header on a Miata for years, and it made power, fit fine, etc, but it still corroded over time in the slip joints, even with nice Nitroplate coating on it. I'm just leary of dealing with it on a daily again.

If there was somebody local who could do the coating I would be less whiny about it, but I don't think there's anybody around here since Nitroplate in Nashville stopped doing direct customer work.

I was really hoping that somebody had tried the Becker headers. I don't even really mind that they're Chinesium if they fit.

[digger]

Weld stainless extension for the slip on part so you can keep it bare and then get it coated inside and out for the mild steel part

[vehicular]

If I'm going to weld anything to the collectors, it will be vbands. My issue was not wanting to clamp slips over the collectors if I could buy the headers already coated. Since you can't get them from IE at all right now, I'm kind of in a bind.

[digger]

Yes there is certainly a lack of quality available which is odd given the popularity of modified m20 is as still very high.