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Location:
Chch, NZ
Registered:
January 2005
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1G query...
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Fri, 14 January 2005 23:13
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I read an article on the net recently about a modified 1G-GTE that stated that 1G's have a set of butterflys "further down" in the inlet manifold (didn't say where) which stay closed at low RPM for better torque and open up for more flow at high RPM... the article advised taking them out for "more power" I've never heard of these before, and don't want to rip my inlet manifold off to find out if they exist, can anyone verify/disprove this?? Im trying to find the article again but havn't had any luck... 
On a seperate note, I'm getting a 1G-GTE HKS single turbo cast manifold flanged for T4 and ext. wastegate, have any of you owned/used one of these and what are they like? Any problems etc?
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Location:
Newcastle
Registered:
May 2004
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Re: 1G query...
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Fri, 14 January 2005 23:35
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no expert on 1G's by any means, but recalling what i read somewhere, only the early 1G-GE had butterflies, i.e i think no turbo or supercharged 1G had butterflies in it. But i wouldnt be surprised if im wrong, do a search and ull probably find what ur looking for.
About the HKS manifold. Its HKS man, it must be good, lol.
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Location:
Brisbane
Registered:
February 2003
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I supported Toymods
Location:
Northern Beaches
Registered:
May 2002
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Re: 1G query...
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Sat, 15 January 2005 02:32
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Yes my 1g-gte has tvis too, but previous owner removed the butter flys, I havn't driven it with them on so don't know if it made much of a difference
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Location:
Rocky Mountains, Canada
Registered:
May 2002
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Re: 1G query...
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Sat, 15 January 2005 11:30
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I thought all 1G-GTE's had TVIS?
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Location:
Adelaide, SA
Registered:
May 2002
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Re: 1G query...
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Sat, 15 January 2005 23:39
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I think they all do... I've looked at 5 or so, gen 1, 2, 3, every one of them had TVIS.
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Registered:
August 2004
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Re: 1G query...
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Sun, 16 January 2005 01:15
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As far as I know, all turbo engines had them, not sure on the NA ones, and supercharged doesn't have them as the intake manifold is different. The problem with them is that the rod that does through the middle goes through every runner except the very front and rear runner, so there are 12 runners, 2 for each cylinder, and the butterflies cover one runner in each of the 2 per cylinder, but due to the design, the rod that passes through the middle, only goes through ports number 2 through 11, and there is nothing at all in 1 and 12, as even in every other port that desn't have a butterfly in it, the rod still has to pass through it to get to the one next to it.
Now, hopefully that wasn't all too confusing, but if you get the gist, the problem is, that that little piece or rod reduces flow by 11cfm, so the manifold flows 11cfm more on cylinders and and 6, not good, as these are 2 cylinders that generally are the first to go when you start melting pistons and stuff. The added problem with this is that the manifold with no butterflies attached already flows 10cfm more air on 1 and 6 on its own, so add the extra 11 cfm, and you have a pretty huge 21cfm more air on cylinder 1 and 6 than every other cylinder.
The manifold flows around 280cfm standard, so thats around 8% or something. Its no big deal in a mild engine, but not good if you are pushing it pretty hard with cooler, turbo and boost, the simple fix is drill and tap a 4mm hole in the ends and install a bolt that just screws straight in, making it the same as every other port, then you only have 10cfm difference to deal with, or 3-4%. They will make vertually no difference to power and should give a reasonable gain down low, so ZI would leave them there.
Cheers..................6BOOST:)
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Location:
PNG
Registered:
June 2002
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Re: 1G query...
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Sun, 16 January 2005 03:01
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Gidday
As`far as I aware all 1ggteu engines have the TVIS system. AND they do make a significant difference to low down drivability. My engines if fairly modified (check readers rides and I think that you will find mine is as modified as much as anyones) and I made a deliberate decision after talking to the bloke that tuned my engine - Jake Edwards - to retain the facility. While I do switch mine with the computer Jake is of the opinion that even if your computer does not have the capability still leave them there as once the engine comes on (decent) boost you loose the vacuum to hold them closed and they get sucked open. If you hold them open all of the time you can see the diference on the dyno and the car feels doughy down low.
Bit more than opinion I have actually tested things.
Craig
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Location:
Chch, NZ
Registered:
January 2005
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Re: 1G query...
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Sun, 16 January 2005 18:51
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Cheers guys, that pretty much tells me all I need to know!
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