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Join Date: Aug 1998
Location: 1000 oaks, CA, USA
Posts: 9
question about cams

Hi everyone, I have a question about cams for my 2.0 rebuild. I currently am setting things up for a rebuild and I was wondering if anyone made a more agressive cam (non-hydraulic, yeah adjustments are a pain but im willing to make a trade off) that I can use with the stock f. i.? I really dont want to go to carbs to use one if I dont have to. What I plan to do in my rebulid is use the euro 2.0 pistons to up the comp. ratio, have the heads opened up a bit, with stainless steel valves, install oil pressure boosters, and a lightened flywheel. The only thing I cant figure out is the cam, anyone have any ideas? If anyone knows about a cam that would work, please let me know, thanks

Old 08-16-1998, 08:00 PM
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Join Date: Aug 1998
Location: 1000 oaks, CA, USA
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Thanks, Brian I aprreciate you taking the time to help. I was under the impression that SS valves were superior to the sodium filled ones, that they disspated heat faster. Oh by the way, If you could send some more specs on your engine, what you did, etc.. I'd really aprreciate it. Would be kinda nice to have a plan to go by, and improvise to my own tastes. When you decked your heads, what did it bring the comp. ratio to? I'd like to build my motor under 9 to 1, yet still get around 110- 115 HP. I saw a type 4 that ran 9.8 to 1 and the pistons were not a pretty sight. Also, if my crank and stock cam are in good shape, which I believe they are, do you think it would be wise to just add on the Euro pistons and heads? My motor has about 40K on a fully stock rebuild by a previous owner. Also, how hard is it to change cranks, cams etc.. I heard it was pretty straight-forward and easy. I'm a bit confused about this whole standard, 0.50, 0.25, thing with bearings, I f anyone can help. thanks, fenton
Old 08-17-1998, 05:57 PM
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Join Date: Dec 1969
Location: Lac La Biche, Alberta, Canada
Posts: 951
I agree with Brian's comments completely. I just went through rebuilding my 2.0 last winter. Someone else appears to have rebuilt it previously and probably less than 20,000 miles previously. What I found was a worn out cam, worn out piston pin bushings and slightly oval big ends on the con rods. Whoever previously rebuilt it, didn't do anything but regrind the crank and stick in new bearings. I also replaced the p&c's with euro's, but did not do anything with the heads (valves and guides were very good, and I also like regular gas). Anyway, I resized the rods and had new pin bushings installed, new stock cam & followers, and reused the original crank. I can't say I notice much power improvement, but the engine does wind up to redline faster than it did, and it now is MUCH quieter mechanically (most of my previous noise was from the worn out pin bushings). I strongly recommend Tom Wilsons book, "How to Rebuild your VW Air Cooled Engine". By the way, as an example,.25 undersize refers to 1/4 of a millimetre removed from the journal surface. This requires the corresponding bearing to be .25 mm thicker.
Old 08-18-1998, 08:40 AM
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Join Date: Dec 1969
Location: Dade County, FL.
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I worked at a NAPA machine shop in Ohio for 3-4 years on and off, (the owner/machinest is a good freind so he would ask me in when he needed help). I only saw 1 911 motor, and maybe 4 different type-IV motors in that time. I can say that there are similarities between domestic engines and VW, but in principle only. An air cooled motor expands/contracts and dissapates heat VERY differently. I would not attempt, or even pay someone (except maybe a VW only shop) to rebuild my motor without reading Tom Wilson's book.
You say your crank is good, but as the previous message states milege is not a good indicator. There are several things, like compression, that should be checked before engine teardown. The parts MUST be marked as they are taken apart if you even HOPE to reuse them. The lifters mate with the cam within the first 5 min. of an engine firing up, the rods and their caps warp into a mating pair. Mark each rod to its cap, and each rod WITH ITS ORIENTATION TO THE FLYWHEEL to the crank. I put each lifter in a small ziplock and label it (intake #3). Don't even think about prying the case apart or it will leak, I have torn apart 3 complete Type-IV motors and each time (of coarse I don't claim to be a brain surgen) I "think" I've taken out all the case bolts (why don't I learn and just count them) I find 2-3 more. As for just dropping in a crank, first have it "miced" at a machine shop, I don't know that magnafluxing is necessary unless the motor spun a bearing or ran hot for a long time, but it is the best way to find cracks. The rods must also be checked, I found mine were still in spec even though the crank needed turning. Also look at the old bearing, if one or two look a lot worse than the others the case may be warped. A cheap check for case warpage is to install the cam with new bearings and see if it spins freely. Here again a shop with line boring ability would be better but it will cost more.
Sorry about the disjointed ramblings, but what I'm hope to have pointed out is that, yes, you can just drop in a cam and crank, but you are taking a HUGE risk as far as longevity and power. With the right tools and information though it is something a reasonable person can do as well, if not better, than VW.
Old 08-18-1998, 02:05 PM
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Location: Lac La Biche, Alberta, Canada
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Tom Wilson's book covers most of the above points. He also is pretty good on describing what can be reused, and what should be replaced.
Old 08-18-1998, 02:22 PM
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