 914/6 Conversion Project, Identifying Engine Specs |
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| Dugo16 |
 Aug 17 2025, 01:29 PM
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#1
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Newbie  Group: Members Posts: 14 Joined: 14-July 03 From: Danville, CA Member No.: 909 Region Association: None  |
I recently picked up a 914/6 conversion project car. I am in the process of trying to figure out what is in the engine without fully disassembling it since it appears to be in good shape. Engine is out of the car. Here is what I know so far.
- 1972 911T Case (911/07) - 90mm Cylinders (90zn2) - K1819n heads (one is a K1819g) - 40IDS3C carbs Trying to figure out what cam and crankshaft are in there. Valve lift measurements below where measured with a dial gauge placed on the valve retainer. - Intake lift .402 - Exhaust lift .376 Stock cam? I figure the crank is a 66mm but it could be also be a 70.4mm from what I have read. Anyway to figure that out without disassembly? Thanks in advance for any info. I appreciate the massive amount of knowledge the 914world community has! -Doug |
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| infraredcalvin |
Aug 17 2025, 05:11 PM
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Distracted Member Group: Members Posts: 1,665 Joined: 25-August 08 From: Ladera Ranch, CA Member No.: 9,463 Region Association: Southern California 
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I’m going through this on a heavily modified 3.4, there is no way to tell until you take it apart. When measuring at the spring you have to take into account the rocker arm ratio… apparently this can vary with a reground cam….
If its a runner, get it tuned best you can, dyno it, compare to stock numbers, if you’re happy enjoy it, or go down the rabbit hole… |
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| Dugo16 |
Aug 18 2025, 10:17 AM
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#3
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Newbie Group: Members Posts: 14 Joined: 14-July 03 From: Danville, CA Member No.: 909 Region Association: None |
QUOTE(infraredcalvin @ Aug 17 2025, 04:11 PM)  If its a runner, get it tuned best you can, dyno it, compare to stock numbers, if you’re happy enjoy it, or go down the rabbit hole… I agree with you, the specs don't really matter since I won't be tearing it apart. It just kills me not knowing exactly what is in there... |
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Posts in this topic
Dugo16 914/6 Conversion Project Aug 17 2025, 01:29 PM
brant 72 year would have come with a 70.4 crank
I think... Aug 17 2025, 01:32 PM Dugo16
I recently picked up a 914/6 conversion project c... Aug 17 2025, 01:47 PM 930cabman :wttc:
Great way to start off with a /6 conversi... Aug 17 2025, 01:57 PM burton73 :wttc:
Please post some pictures
Best Bob B Aug 17 2025, 05:12 PM targa72e for early cranks 2 plugs on flywheel end is 66mm o... Aug 17 2025, 10:41 PM
Dugo16
for early cranks 2 plugs on flywheel end is 66mm ... Aug 18 2025, 10:14 AM porschetub
for early cranks 2 plugs on flywheel end is 66mm... Aug 18 2025, 05:49 PM sixnotfour
[quote name='Dugo16' post='3219970' date='Aug 19 ... Aug 18 2025, 06:46 PM sixnotfour https://www.drcamshafts.com/911profiles.htm Aug 18 2025, 07:32 AM sixnotfour might want to price check IDS webers... Aug 18 2025, 07:35 AM brant
might want to price check IDS webers...
I saw t... Aug 18 2025, 09:21 AM 930cabman
might want to price check IDS webers...
I saw ... Aug 18 2025, 09:40 AM Dugo16
[quote name='sixnotfour' post='32199... Aug 18 2025, 10:22 AM brant That carb has one difference though that makes it ... Aug 18 2025, 10:11 AM Dugo16 Moving on to the clutch and trans.
Clutch disc on... Aug 18 2025, 11:43 AM porschetub
Moving on to the clutch and trans.
Clutch disc o... Aug 18 2025, 06:11 PM Dugo16
You can most likely reuse that clutch disk but no... Aug 18 2025, 09:25 PM DennisV
Trying to figure out what cam and crankshaft are ... Aug 19 2025, 09:58 AM |
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