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Hi all,

I'm after an exhaust replacement for an '89 Brumby to give me the usual power increase, that fulfilling boxer sound out the rear and not too hugely loud at highway speeds.

I'm toying between a 2 1/4 inch cat back system or going the whole hog with custom headers from the block. What extra gain is there performance and sound wise with going headers as well on an EA81?

Cheers.

Headers arent really gonna do squat

cant do headers on an EA82 atleast, the shape of the engine and placement

cat back for the noise is all your gonna gett

they are headers or extractors. Some have used EA82 headers on EA81 due to larger diameter allegedly, I'd be cautious to try used before buying EA82 just in case you lose a bit of back pressure, too much a bit may be felt as a loss of torque.

Found the opportunity to open the throttle right up on a favourite long haul uphill test track (where a snap happy van rests on the blind spot ) Got the old 92 Brumby with standard exhaust yet modded intake throttle body and LPG saw 110 kph in third which is not much slower than my EA82T in same place, doubting standard exhaust is much of a power hindrance. I do recall a 2" system helped the choke splutter when cold though

Usually people put "headers" or "extractors" on cars to replace restrictive factory manifolds. The EA81 and EA82 exhaust manifold basically are extractors already. Look at them - they are just two pipes. The only way to really change them is by going larger diameter, but if you look at the size of the exhaust ports themselves, it's really not going to yield any benefit at all. End of the day it's not a performance engine, even if there was a tiny gain it wouldn't be worth the cost anyway.

any real gain may just be in the head - still, a gain

AndrewT wrote:The EA81 and EA82 exhaust manifold basically are extractors already. Look at them - they are just two pipes. The only way to really change them is by going larger diameter, but if you look at the size of the exhaust ports themselves, it's really not going to yield any benefit at all. End of the day it's not a performance engine, even if there was a tiny gain it wouldn't be worth the cost anyway.

This is the opinion I had formed and my reason for creating this thread. Thanks AndrewT and all above.

if you are game enough to machine the exhaust ports to a larger diameter you engine would make more noise but would have less back pressure leading to eventual engine failure. going to 2 inch headers will increase gas flow marginally (no performance gain) but will add noise effect (kinda like a farting leper)

TOONGA

yep in an odd mood today blame Maddox

waste of time and money for power increases. Cat back 2 1/4 zorst will sound good with strait thru mufflers.

you may think it goes quicker, but its just the noise making you think youre going quicker. been there done that...lol.

alex

Alex...you will need to wait for my photo thread in January next year. All shall be revealed to you!

Alex wrote:waste of time and money for power increases. Cat back 2 1/4 zorst will sound good with strait thru mufflers.

you may think it goes quicker, but its just the noise making you think youre going quicker. been there done that...lol.

Unless you've got an EJ and running the standard EA exhaust after the Y pipes its probably not going to do you much. I definitely had a power increase going from the EA exhaust after the EJ Y pipes to a 2 and a 1/4 inch cat back system. Got a better note too. Could be refined more but I'm too tight atm with funds to be spending it on exhaust systems...

Cheers

Bennie