OBX vs. Thunder Header

[SeminoleMan]

I'm about to experiment with a longer 4-2-1 set from another Chinese company, and I'll be able to get a dyno comparison for the two.

Be sure to let us know the results. I for one would prefer a 4-2-1 arrangement. I really wanted the AWR header but couldn't get one before they stopped production. I'd rather not sacrifice torque down low for top-end increases. Most of my driving is done below 5k revs, so more (relative to a 4-1 design) low to mid-range punch would be a bonus.

 

[StealthWyvern]

reported

 

[aMaff]

reported

Deleted, thanks


It's hard to track these morons down when they don't start threads, as, while I try, I don't usually have time to read every single thread out there

PS: you missed 2 in the MS3 lounge and FS sections lol

 

[StealthWyvern]

Deleted, thanks


It's hard to track these morons down when they don't start threads, as, while I try, I don't usually have time to read every single thread out there

PS: you missed 2 in the MS3 lounge and FS sections lol

no i didn't! Figured you would just track his name down! lol

 

[SeminoleMan]

So, with all the Thunder headers sold, no one has anything more than a "butt dyno" of what the true gains are?

 

[jmoneycruz724]

Can anyone give me a website on where to buy headers, i dont really trust ebay too much?

 

[Captain KRM P5]

we carry the obx. we'd carry the thunder as well but the price most people were not willing to pay.

 

[niky]

It's kind of hard to get a dyno of the thunder as most of us who went for it went for it because it was cheap and it was available... not because of the "mad powah" we were going to get from it.

Best I can say is it's possibly 5-8 hp... my set-up pre-tuning was 20 hp more than a stock motor on a Dastek, about 18 on a Dynojet... but I don't know what kind of gas he had in the tank and what condition his motor and motor oil were in. Of that, I'm sure 12-14 was from my intake and exhaust (from dynos with thunder+nothing to thunder+exhaust, which means about 4-8 hp from the header, cat-delete and better motor oil.

Like I've said, you get a good "kick" from the removal of the cat, but the gains aren't impressive otherwise.

 

[triikster]

I installed the OBX on my 02 MINI Cooper S and it added quite a bit of low end torque, but have noticed that my automatic P5 (which came with an OBX header) does lack low end torque compared to manual that I also test drove (though the manual to automatic comparison may have something to do with this too.)

 

[aMaff]

(though the manual to automatic comparison may have something to do with this too.)

it has everything to do with it.

 

[TreFlip999]

The OBX fit like a glove..no rubbing issues for me..Gives the sum' b**** a nice growl too

 

[velothree]

Most of the thunder gains are from the loss of the first cat... the removal of the cat produces a good hump of torque.

But from where I'm sitting on it, it doesn't make an optimal amount of low-end torque, for me. I'm about to experiment with a longer 4-2-1 set from another Chinese company, and I'll be able to get a dyno comparison for the two.

Against completely stock, it feels like a good hump at 3000 rpm and about 4-5 at redline... but a set of longer tubes with a better merge collector (the Thunder has a short, restrictive merge) should do much more.

Any update on this 4-2-1 header from another Chinese company? Where'd you get it from?

 

[niky]

Liangfei... but it's for the 626, so it'll take some fabbing after the secondaries to fit.

But for them to ship one to you guys, they'll need a group order... a big group order. I'm only getting mine because my friendly neighborhood shop is getting it as a sample.

They have ceramic coated, stainless and chrome. I'm getting the stainless because we'd probably ruin the ceramic coating by cutting and welding it at the shop.

 

[i12drivemyMP5]

The length of 4-2-1's are generally longer than stock or 4-1's so a new (or altered) midpipe will be necessary anyway. Does this 4-2-1 have the flex piece already on it?

 

[NDN]

what is the diference between 4-1 headers and 4-2-1 header,
sorry i'm kind of new to all of this

thanks
Martin

 

[ProtoType5]

Runner length is the difference....In a exhaust manifold, ideally you would like the exhaust pulse from 1 cyclinder to be exiting the runner to the collector at a precise moment at or slightly prior to the next cylinder firing...This creates a exhuast pulse which helps pull the exhaust gases out of the cylinder faster and more efficiently.....A 4-2-1 header for our cars allows you to tune the exhaust runner lengths to a useable RPM range, like 4500-5500, unlike the 4-1 manifolds which have lengths more condusive with RPM ranges from probably 5500 to 6500, and we all know the FS-DE make no power after 6K...

 

[i12drivemyMP5]

All this talk about 4-2-1 makes me dream of the day that the mazda racing 4-2-1 in my garage finally gets the blue or silver polydyn coating & a midpipe to fit it up done so I can give the OBX 4-1 a rest. So many projects, so little time.

 

[SeminoleMan]

But for them to ship one to you guys, they'll need a group order... a big group order.

The 4-2-1 is definitely interesting especially if it comes with a flex section, but it'll be hard to put together a big group buy for a yet unseen and tested product. Please post some pictures when you get the fab completed and the header installed

 

[i12drivemyMP5]

The one I have has it already. Would be nice to bring peak pwr down a grand or so.

 

[bermankahns]

Liangfei... but it's for the 626, so it'll take some fabbing after the secondaries to fit.

But for them to ship one to you guys, they'll need a group order... a big group order. I'm only getting mine because my friendly neighborhood shop is getting it as a sample.

They have ceramic coated, stainless and chrome. I'm getting the stainless because we'd probably ruin the ceramic coating by cutting and welding it at the shop.

do you have a pic of the headers while they are out of the car? i might want to try to fab my own in the future, but i want to see the design before i try it.