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tasfalen |
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#1
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Newbie ![]() Group: Members Posts: 22 Joined: 23-June 04 From: Victoria, BC Member No.: 2,239 ![]() |
Hi all,
I have a '72 914. I am assuming its a 1.7 but I don't know what - if anything - has been done to it. The guy I bought it from claimed that the engine had been rebuilt. Two questions: 1. What can I expect from a 1.7? any way to find out if its been bored out? it really feels pretty torquey. 2. Its been converted to dual Webers and is absolutely swallowing gas. Any idea what the optimum jetting is for this configuration? Cheers, Jason Victoria BC Canada '72 914 |
lapuwali |
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#2
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Not another one! ![]() ![]() ![]() ![]() Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 ![]() ![]() |
Only way to tell if it's been bored or had new cylinders fitted is to pull a head and measure. The bore will be 80mm if stock. It's very common to fit 94mm (stock 2.0) or 96mm (common overbore of 2.0) cylinders on the 1.7 66mm crank to get a 1.9L engine. Webers on most cars do indeed drink gas. 15-20mpg is commonplace. I'm told you can do much better with some tuning of the whole engine (cam and head work), but most people seem to get about this mileage on a stock or near-stock engine with Webers on it.
The common jetting for a 1.7 is 115 mains, 200 airs, 50 idles. 52 and 55 idles are common, and make gas mileage worse, as it will remain on the idle jets until 3000rpm or thereabouts. Ignition timing also has an effect, and when switching to Webers it's all too common to fit a VW 009 distributor, which has entirely the wrong advance curve for the engine. |
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