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Location:
Adelaide
Registered:
May 2003
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Re: 4A: G vs F heads
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Wed, 27 October 2004 21:52
 
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| drift86levin wrote on Mon, 25 October 2004 13:03 |
i heard along the grapevine that the F heads are better for turbo applications..something about the steep valve angle and the short port legth works well with it..very responsive..have a look at the starlet 4E-FTE..i haven't heard of a 4E-GTE..toyota must have done some reaserch into this..and developed that head for a reason..it might fall into the catagory of less that 45 deg between valves, but buy no means is it a economical grandmas car!
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Now here is something i meant to reply to last night. I dont think that the 4E-FTE came about through some huge amount of research and development from Toyota, but rather through slapping a turbo on an already existing engine (4E-FE). Same as the ubiquitous 4A-GZE it was a development on an already existing engine design. If you look at the cutouts on the GZE pistons compared to the GE pistons you can see that they are completely flat apart from minor cutouts in the piston. I think this is to compensate for the valve angle for proper flame propogation. Although i honestly dont think it matters so much for the applications which Toyota wanted these for. I doubt much R&D has gone into the 4A-GZE and the 4E-FTE and rather they were created as Toyota wanted supercharged and turbocharged cars in their lower end lineup.
I am guessing there must be some rhyme and reason behind the HUGE number of R&D hours which have gone into the 3S-GTE and 2JZ-GTE engines, especially when they are used in JGTC format. Why didnt they go to F heads on these engines, especially when the power is at a premium. I mean they already spend tens of millions on custom parts for these engines, so why not slap an F head on them if it is more efficient. Somehow i think that it isnt more efficient, and rather the G head provides an advantage somehow.
Now as for what that advantage is i think i have a bit of a clue. From driving both my 4AGE and my dad's 4AFE i think the advantage lies in the RPM range which the engine provides power, as i alluded to in my first "essay". With an F head the flow and flame characteristics would probably limit the power and torque band much more narrowly. Wheras the G heads have a repeatedly shown wide power band, which for the 4AGE starts from around 4500 and goes to 7500rpm in stock configuration. This wide power band of the G head woudl give drivers an advantage over those who had a narrow power band of the F head, mainly because of gear changes. Even if an F head flows signficantly more over 1000rpm and produces more power there, the gearing would need to be set up so closely for that 1000rpm that the driver woudl be changing gears every couple of seconds. However, for the G head given a 3000rpm power band in stock configuration (commonly 2500rpm in modified) this gives a much longer time in each gear, and therefore removes one of the slowest parts of racing, gearchanging.
Now you say, why dont they just go to a flatshift type antilag system, or something similar. Well i woudl guess that the regs would get in the way, and they woudlnt be allowed. Just like i cant add a flatshift system and still stay in Supersprint
Comments?
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4A: G vs F heads
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Henn | Thu, 21 October 2004 13:47 |
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Re: 4A: G vs F heads
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Norbie | Fri, 22 October 2004 00:06 |
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Re: 4A: G vs F heads
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rob_RA40 | Fri, 22 October 2004 00:09 |
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Re: 4A: G vs F heads
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b1gb3n | Fri, 22 October 2004 02:26 |
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Re: 4A: G vs F heads
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rob_RA40 | Fri, 22 October 2004 04:51 |
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Re: 4A: G vs F heads
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b1gb3n | Fri, 22 October 2004 06:15 |
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Re: 4A: G vs F heads
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Bill Sherwood | Fri, 22 October 2004 04:01 |
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Re: 4A: G vs F heads
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EVOSTi | Fri, 22 October 2004 06:15 |
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Re: 4A: G vs F heads
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ae95 | Fri, 22 October 2004 06:19 |
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Re: 4A: G vs F heads
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SEXY 16 | Fri, 22 October 2004 06:41 |
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Re: 4A: G vs F heads
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wuzah? | Fri, 22 October 2004 10:51 |
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Re: 4A: G vs F heads
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NuGeN | Fri, 22 October 2004 11:41 |
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Re: 4A: G vs F heads
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Henn | Fri, 22 October 2004 13:34 |
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Re: 4A: G vs F heads
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Bill Sherwood | Fri, 22 October 2004 14:16 |
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Re: 4A: G vs F heads
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Henn | Fri, 22 October 2004 15:13 |
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Re: 4A: G vs F heads
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cwhelan | Mon, 25 October 2004 01:59 |
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Re: 4A: G vs F heads
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drift86levin | Mon, 25 October 2004 03:03 |
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Re: 4A: G vs F heads
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b1gb3n | Mon, 25 October 2004 07:53 |
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Re: 4A: G vs F heads
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takai | Wed, 27 October 2004 21:52 |
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Re: 4A: G vs F heads
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SEXY 16 | Mon, 25 October 2004 09:23 |
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Re: 4A: G vs F heads
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Bill Sherwood | Mon, 25 October 2004 10:09 |
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Re: 4A: G vs F heads
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SEXY 16 | Mon, 25 October 2004 21:27 |
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Re: 4A: G vs F heads
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Johnny | Tue, 26 October 2004 02:27 |
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Re: 4A: G vs F heads
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Bill Sherwood | Tue, 26 October 2004 02:57 |
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Re: 4A: G vs F heads
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Shraka | Tue, 26 October 2004 03:02 |
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Re: 4A: G vs F heads
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Bill Sherwood | Tue, 26 October 2004 03:42 |
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Re: 4A: G vs F heads
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Norbie | Tue, 26 October 2004 03:33 |
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Re: 4A: G vs F heads
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mrshin | Tue, 26 October 2004 04:15 |
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Re: 4A: G vs F heads
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Shraka | Tue, 26 October 2004 04:53 |
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Re: 4A: G vs F heads
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Bill Sherwood | Tue, 26 October 2004 05:04 |
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Re: 4A: G vs F heads
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b1gb3n | Tue, 26 October 2004 05:04 |
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Re: 4A: G vs F heads
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Bill Sherwood | Tue, 26 October 2004 06:28 |
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Re: 4A: G vs F heads
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Shraka | Tue, 26 October 2004 06:45 |
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Re: 4A: G vs F heads
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mrshin | Tue, 26 October 2004 06:17 |
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Re: 4A: G vs F heads
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Norbie | Tue, 26 October 2004 06:51 |
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Re: 4A: G vs F heads
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Shraka | Tue, 26 October 2004 07:25 |
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Re: 4A: G vs F heads
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Bill Sherwood | Tue, 26 October 2004 07:53 |
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Re: 4A: G vs F heads
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Johnny | Tue, 26 October 2004 10:49 |
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Re: 4A: G vs F heads
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mrshin | Tue, 26 October 2004 14:17 |
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Re: 4A: G vs F heads
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oldcorollas | Tue, 26 October 2004 14:27 |
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Re: 4A: G vs F heads
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mrshin | Tue, 26 October 2004 14:36 |
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Re: 4A: G vs F heads
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quest | Tue, 26 October 2004 15:36 |
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Re: 4A: G vs F heads
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b1gb3n | Tue, 26 October 2004 15:48 |
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Re: 4A: G vs F heads
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4DaDrift | Tue, 26 October 2004 15:50 |
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Re: 4A: G vs F heads
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Shraka | Wed, 27 October 2004 00:08 |
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Re: 4A: G vs F heads
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Bill Sherwood | Wed, 27 October 2004 01:49 |
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Re: 4A: G vs F heads
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oldcorollas | Wed, 27 October 2004 15:22 |
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Re: 4A: G vs F heads
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Tofuboi | Tue, 26 October 2004 21:53 |
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Re: 4A: G vs F heads
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Shraka | Wed, 27 October 2004 02:02 |
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Re: 4A: G vs F heads
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quest | Wed, 27 October 2004 06:30 |
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Re: 4A: G vs F heads
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quest | Wed, 27 October 2004 06:59 |
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Re: 4A: G vs F heads
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quest | Wed, 27 October 2004 07:21 |
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Re: 4A: G vs F heads
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oldcorollas | Wed, 27 October 2004 07:34 |
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Re: 4A: G vs F heads
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Henn | Wed, 27 October 2004 06:58 |
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Re: 4A: G vs F heads
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Shraka | Wed, 27 October 2004 07:31 |
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Re: 4A: G vs F heads
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takai | Wed, 27 October 2004 07:58 |
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Re: 4A: G vs F heads
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quest | Wed, 27 October 2004 14:32 |
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Re: 4A: G vs F heads
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oldcorollas | Wed, 27 October 2004 15:08 |
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Re: 4A: G vs F heads
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Tats | Wed, 27 October 2004 23:26 |
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Re: 4A: G vs F heads
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Johnny | Thu, 28 October 2004 00:48 |
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Re: 4A: G vs F heads
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Shraka | Thu, 28 October 2004 02:21 |
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Re: 4A: G vs F heads
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Johnny | Thu, 28 October 2004 03:44 |
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Re: 4A: G vs F heads
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Bill Sherwood | Thu, 28 October 2004 04:30 |
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Re: 4A: G vs F heads
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b1gb3n | Thu, 28 October 2004 05:24 |
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Re: 4A: G vs F heads
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koen | Thu, 28 October 2004 04:52 |
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Re: 4A: G vs F heads
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Norbie | Thu, 28 October 2004 05:09 |
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Re: 4A: G vs F heads
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justcallmefrank | Thu, 28 October 2004 05:24 |
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Re: 4A: G vs F heads
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Bill Sherwood | Thu, 28 October 2004 05:17 |
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Re: 4A: G vs F heads
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Bill Sherwood | Thu, 28 October 2004 05:29 |
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Re: 4A: G vs F heads
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oldcorollas | Tue, 02 November 2004 08:10 |
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Re: 4A: G vs F heads
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Shraka | Thu, 28 October 2004 07:05 |
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Re: 4A: G vs F heads
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da_horse | Thu, 28 October 2004 08:36 |
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Re: 4A: G vs F heads
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justcallmefrank | Thu, 28 October 2004 08:45 |
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Re: 4A: G vs F heads
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Shraka | Mon, 01 November 2004 03:10 |
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Re: 4A: G vs F heads
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justcallmefrank | Mon, 01 November 2004 03:11 |
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Re: 4A: G vs F heads
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Shraka | Mon, 01 November 2004 03:18 |
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Re: 4A: G vs F heads
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86tt | Mon, 01 November 2004 14:15 |
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Re: 4A: G vs F heads
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takai | Tue, 02 November 2004 07:41 |
