M20 Header Options in 2019

[moatilliatta]

AAF headers?

[vehicular]

I've never seen AAF headers before now. Are there any tests out there other than their own claims? I'm willing to buy that their 6-3-1 configuration might make more power than traditional 6-2 BMW headers, but I don't about 1 3/4" primaries, and I especially don't know about their dramatically unequal primary lengths.

[moatilliatta]

Whats your HP goal?

[digger]

Who is AAF ?

[e30austin]

Advanced Auto Fabrication, out of Spokane, Washington, USA. Popular amongst the PRO-3 crowd.

[vehicular]

Whats your HP goal?

Bout tree fiddy.

I had about a novel typed up to explain that I'm not really the scrub that this thread probably makes me sounds like, but... I guess I just want whatever I can get out of a reasonable street motor? I'm not trying to do an F1 engine dev program, just build a warmed up street car with good manners, AC, low enough compression that I can run 89 without pinging it to death, etc.

I'd be happy with 200-225whp, it sounding cool, and the motor looking like it belongs in the engine bay.

[vehicular]

Who is AAF ?

This:

https://advancedautofab.com/p/aaf-m20-race-header/

[digger]

Quality looks good construction wise and they don't have shitty bends right at the flange like some.

I dont get why make bold claims quoting exact numbers and not back them up with proper evidence about exactly what was compared (exhaust setup and engine specs) and the outcome in terms of dyno sheet overlays ? It would be much more credible. It always pays to remember the exhaust is a system and what happens after the primary is probably as important as the primary itself which comes back to what the comparison was and why any changes occurred.

Some casual observations are the pipe sizes are way larger than what is recommended by some of the best professional exhaust guys out there have found works best. Those sizes are capable of probably 500bhp atleast so how effective can they really be on a 250hp engine where the port is lucky to be 1-1/4"?

There are people that push 6-3, 6-2 or 6-1 but the differences are going to better in some areas and worse in others. There is no magic solution that bests all that's just how wave tuning works you get positive and negative waves.

6-2 is usually chosen because of easier packaiging plus with 240* separation of pulses there isn't much need for 360* separation that the 6-3 produces. 6-1 might be able to make more peak within a narrow rpm band as the strength of scavenging should be a bit higher but you lose out elsewhere.

I haven't tested all the different configurations but 1D simulations predict it's not worth deviating from a tried and true 6-2 when I do my custom set soon.

[vehicular]

when I do my custom set soon.

I just caught this. Any interest in selling those BTBs ;D

[vehicular]

I just called IE, and the sales(?) girl said that they would have headers "within a month" for whatever that's worth.

[digger]

I just caught this. Any interest in selling those BTBs ;D

At some point I'll unload one of the sets lol but not any time soon

[digger]

I just called IE, and the sales(?) girl said that they would have headers "within a month" for whatever that's worth.

Contact Rama from RHD. At one point he was going make a batch. He made a prototype that looked better than anything currently on the market (pics/were are on his Facebook from a couple years back). I don't know if it's still planning to go ahead or whether it fell to the wayside

[vehicular]

At some point I'll unload one of the sets lol but not any time soon

ONE of the sets... guy...

Contact Rama from RHD. At one point he was going make a batch. He made a prototype that looked better than anything currently on the market (pics/were are on his Facebook from a couple years back). I don't know if it's still planning to go ahead or whether it fell to the wayside

I sent him a message on Facespace. He last posted pics of them in 2016. My hopes are not high.

[digger]

ONE of the sets... guy...



I sent him a message on Facespace. He last posted pics of them in 2016. My hopes are not high.

Every time you get rid of something you realise that you wanted to keep it.

[zaq123]

Quality looks good construction wise and they don't have shitty bends right at the flange like some.

do you mean RD headers?