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Hey team,

Long story short...
I fitted a 42mm radiator last weekend - and as I put it all back together, this big chunky part you can see is on the standard intake pipe between air flow meter and throttle body. Its up against the radiator fan and has seemed to push the bendy part of the intake pipe, and sits out of wack - not quitre right!

Do I need it?

With it there, it makes the bendy part of the intake squashed and the car just feels like it doesnt have the responce it did before.

So,
do I need it?
how do I get rid of it if I dont need it?

Cheers,
Chris!

Hey Chris,
Good job today, seems like you had fun. Anyday you come home with a straight car, less fuel and rubber has gotta be a bloody good day

First piccy, you will need to move your after market intake towards the firewall so the pipe work flows, no kinks at all.

Second piccy, the box hanging off the crossover is there to quieten the intake, ie stock setup. You can remove it but make sure you plug up the hole so it can't suck in any crap. You may lose a small amount of mid range power but probably not too much. I had a similiar problem when I fitted bigger rad to Scooter. At the moment I'm working on a new intake set up but still coming across to the left side of the motor so I don't lose any midrange power. I'll post up when I finish it.

Terry

It's a resonating chamber to flatten out a dip in torque ~3500 rpm

The second picture is of the Helmholtz resonator chamber. It actually increases the torque at certain rev ranges.

See more here;

http://forum.miata.net/vb/showthread.php?t=23476

http://www.phys.unsw.edu.au/jw/Helmholtz.html

http://forum.miata.net/vb/search.php?searchid=3841221
J

Terry,
Thanks for the reply mate!

Yes it was a tops day racing and I cannot wait for next race meet!!!!! I didnt come last!~! hehehehe

Cool,
I'll adjust the intake part so I can put the mania pipe a bit further back to straighten the kink. Why didnt I think of that! LOL


Thanks Broady and Juffa also - I cannot afford to lose any more power/torque so might keep it and adjust the intake pipe! lol

Cheers,
Chris

Chris, it looks like you still have the original NA8 cross pipe, if so you can replace it with an NB8 crosspipe for a little more torque. Reason is the bend in the crosspipe at the other end, i.e. the throttle body end, has been flattened to accommodate the top radiator hose. A little modification to pipes is required to fit, but not much.

Btw, you might find this thread where someone dyno'd variations on the crosspipe, i.e. helmholtz V no helmholtz resonator of interest.
viewtopic.php?f=29&t=34361

Thanks mate!
I'll look into that now!
when you say little mod is needed, such as? (Im a n00b with mechanical and tools with cars LOL )

Good read in that thread too - dropped a bit of power without it!

An aftermarket ECU can fix the aftermarket intake. With the standard computer my car was pretty numb to drive. The response and torque went up quite a bit with a tune. That was with the racing beat 4-1 and 2.25 SMB exhaust. Plus an elbow join to a pod( very short intake). I ended doing the cut-up typhoon setup. All in all there's no dip at all with the helmholz box removed. Should be a dyno and underbonnet pic in the garage section on my car. I didn't have to cut anything and Im running the 52mm cooling pro radiator. My intake is piped to the foglight now. That's on an NB8B though.

Hellmun wrote:An aftermarket ECU can fix the aftermarket intake. With the standard computer my car was pretty numb to drive. The response and torque went up quite a bit with a tune. That was with the racing beat 4-1 and 2.25 SMB exhaust. Plus an elbow join to a pod( very short intake). I ended doing the cut-up typhoon setup. All in all there's no dip at all with the helmholz box removed. Should be a dyno and underbonnet pic in the garage section on my car. I didn't have to cut anything and Im running the 52mm cooling pro radiator. My intake is piped to the foglight now. That's on an NB8B though.

looking forward to it mate

evil_weevil wrote:When you say little mod is needed, such as? (Im a n00b with mechanical and tools with cars LOL)

This hopefully explains it in sufficient detail:
viewtopic.php?f=29&t=34875&p=452542&hilit=crosspipe#p452542

93 clubman - dude, you are awesome!!!

thanks for the link with that thread mate, appreicate it!

Cheers,
Chris

93 clubman,
Just wondering - big favour! Can you please post a pic of youe engine bay with the pipe?

Thanks mate!

Chris

Oh and what series NB pipe is it? cheers!

evil_weevil wrote:Can you please post a pic of youe engine bay with the pipe?

evil_weevil wrote:Oh and what series NB pipe is it?

Any NB8 OEM crosspipe should fit, but I'm not absolutely certain they all have the Helmholtz resonator attached. Also, see the 2nd last post on this old thread as it explains the minor mods required in a bit more detail: viewtopic.php?f=29&t=16931&hilit&start=15

NB8A don't have it
NB8B-C do have it