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Old 11-07-2004, 04:18 PM   #1
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Default TB bolt pattern

I traced the back of my throttlebody and wrote down a few measurements. I'm curious to see if the pattern will fit any L27s or series 1 L67s.
Here'* the pic.

The rear passage of the throttlebody flares out pretty wide to meet up the L36 upperintake but the ser2 L67 TB (69mm) keeps a round exit. Both of these TB'* have the same bolt pattern and the arrangement of the Butterfly plate has the same center.
Oh, and where it says 'set lower', it is about 1mm away from sealing up with the upperintake manifold. Everything in the center is a positive seal.(cept for the coolant passages)
So series 1 guys check it out, you may have some more options.
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Old 11-07-2004, 04:28 PM   #2
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I don't think it will work for us. From doing a visual comparison of my 1994 L27 to my 1998 L36 where the TB goes into the UIM the L36 TB is larger, not only for air coming, but the overall physical size and bolt pattern. Would require a custom UIM or SC opening.
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Old 11-07-2004, 05:21 PM   #3
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I'll have an answer for you on the 92/93 and 94/95 L67 hopefully monday. Still looking for my old gasket, but I have the tracing of the 94/95 already.
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Old 11-07-2004, 05:55 PM   #4
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Nope, doesn't look like mine. I have a round 58mm bore.
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Old 11-07-2004, 08:46 PM   #5
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The castings are very similar if not totally similar, however Dame is correct, our outlet is round... Although i'd rather modify an outlet then bore an entire TB bigger if you catch my drift
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Old 11-07-2004, 09:29 PM   #6
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I figured that this L36 TB would not fit an L27 b/c of the rear opening opening up to the l36 uim. (the series 1 TB'* are rotated?) BUT the ser2 L67 has a 69mm ROUND exit with the SAME bolt pattern. Now if these bolt patterns are the same on the L27 and ser1 L67, then L27ers can swap in ser1 L67, L27, or L36 TBs. I wasn't just thinking that this particular TB could fit ont the l27.
Come on i know someone is bored enough to see if the bolt pattern is the same.
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Old 11-07-2004, 09:56 PM   #7
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I already know the 92/93 L67 is the same as the 94/95 L67 for stud location, but they differ slightly for the coolant passage. A custom cut gasket solves this problem. However, I don't have a clue about how they relate to the L36. Yet.
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Old 11-07-2004, 10:05 PM   #8
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Yeah, the custom cut gasket is the way i went but it was a little easier since i don't have any coolant running up there.(ZZP HVII insert blocks it)
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Old 11-07-2004, 10:07 PM   #9
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Oh... I guess I'll go grab my stock TB and measure the bolt pattern...
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Old 11-07-2004, 10:12 PM   #10
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One issue with a larger TB on the L27 is boring the manifold opening. Damemorder was telling me how thin it is, and boring plastic isn't easy, and it may not support the weight then.

However, strengthening isn't hard either.

Dame go work on that TB for me then
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