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extractors on a kombi 76 2ltr is it worth it??????
kombi_76er - December 14th, 2003 at 11:00 AM

i was considering putting extractor on my 76 2ltr kombi and i wanted to know is it worth it??
what benefits do i get from it eg. fuel consumption??, and if it adds much power?


bigbruvabob - December 14th, 2003 at 11:22 AM

have been looking into this myself for my bugs i believe you make it breathe better by getting rid of the gas better which increases horsepower. more importantly it allows the engine to run cooler which is good in oz u will have to jet up one size in your carbs to allow for engines better breathing. in some cases if you use extractors you will lose the heating depending on which extractors you get. this is all theory on my part as i am yet to make the change myself. i tend to be time short and like to shop on the net but have been unable to find any good oz based sites to get stuff from and so am still searching for extractor options apparently thunderbirds r the go but i cant find any prices


Menangler - December 14th, 2003 at 02:42 PM

I found on a stock 2 litre the standard German muffler works the best, gave much more bottom end performance than a Thunderbird.
But on a hotty 2 litre with 44 IDF Webers, 8.5 to 1 comp and 1800 heads, the thunderbird worked the best.


bigbruvabob - December 15th, 2003 at 05:32 PM

what effect on heat exchange? somebody told me that extractors let your motor cool better at this point in time i am looking at extractors for my girls hebmuller copy. the fibreglass work has messed with the cooling and therefore overheating has been a problem have installed an undercar scoop which helps heaps but anything that can help cool i must consider. extractors were suggested but have had conflicting opinions it is a fairly stock 16oo at moment.


Purple Martin - December 16th, 2003 at 09:46 AM

The problem with extractors is that most of them cause serious icing in the intake manifolds. This is because they don't have a well-designed hot gas return pipe (like the stock exhaust does). The icing causes a loss of power which more than cancels out any gain you might have got from the extractor, which is why stock is often better.

NOTE: Icing can occur just as easily on a hot summer's day, because it's caused by low pressure condensation. Don't assume that just because you live in a warm climate you're immune, because you're not!


Andy - December 16th, 2003 at 12:37 PM

Good point on icing.
Just remember on a stock type 4 motor setup, hot air is drawn in off the heads/barrels (controlled by thermostat) and the inlet relies on short manifolds to prevent icing.
It doesn't use the exhaust port to muffler hot air flow as in the stock single carb type 1 motor.
:thumb


Grunk - December 16th, 2003 at 05:59 PM

I don't really understand the tech details but I had a stock 2L '76 kombi many moons ago. Replaced the burnt-out standard muffler with extractors and noticed an immediate drop in power. :o Was I disappointed! After a few months I replaced the extractors with a new stock muffler and power came back. Fuel economy got better as well. It was 20 years ago and I can't remember the brand of extractors, but they were probably pretty crappy (I got 'em cos they were cheap - hah). Maybe decent ones perform better.


kombikim - December 16th, 2003 at 10:46 PM

unfortunately there does not seem to be anything better than the standard muffler setup, & that is general opinion worldwide, certainly nothing readily available & affordable,if somethng does actually turn up I would love to know about it:jesus


KruizinKombi - December 17th, 2003 at 11:50 PM

I agree, I like the standard muffler best. The only thing cheap extractors are good for (on a stock motor) is their exhaust note.


57 Panel - December 18th, 2003 at 08:09 AM

I'm putting a new German muffler on this weekend. I've got extractors on at the moment so I'll tell you if there is a change in performance. Hopefully they'll be a little quieter too.:bounce


kombi_kid - December 18th, 2003 at 08:22 AM

use are all too old gotta have the sound!
ahahahahahaha
cheers
rhys


wibble - December 18th, 2003 at 09:28 AM

I had a good torque increase but seemed to lack top end revs when I replaced hot dog type muffler with german item, although no tuning was done at the time.


KruizinKombi - December 18th, 2003 at 09:32 AM

That's exactly the difference between the two systems wibble. The extractors may seem faster because the engine can rev more freely, but I'm quite convinced that the bus will actually accelerate better with the stocker, while also creating less noise and using less juice (lower revs). The difference is even more noticable when you start taking the bus off-road. :thumb


wibble - December 18th, 2003 at 10:48 PM

yeah I noticed a real difference off the tarmac, also replacing the standerd air filter with a finer filter (or similer high flow) made a fair difference on mine as well..


57 Panel - December 22nd, 2003 at 08:18 AM

I fitted the muffler yesterday arvo. Alot quieter, couldn't take it for a drive because it took several beers to fit but I'll let you know how it goes after I drive to Sydney tomorrow:thumb


KruizinKombi - December 23rd, 2003 at 09:10 AM

LOL!! :D:thumb:beer:beer:beer


57 Panel - December 23rd, 2003 at 08:29 PM

The standard muffler made a difference. My bus stayed at 90 going up the hill at Mooney Mooney bridge, normaly have to change down for hills like that. It's also very quiet, stopped at the lights at the end of the freeway and thought the engine stalled. It also pulls better when I take off on a hill.:thumb


Grunk - December 23rd, 2003 at 09:37 PM

I love a happy ending......:bounce