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Walt Fricke Walt Fricke is offline
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Join Date: May 2004
Location: Boulder, Colorado
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There is actually quite a lot that you could use from your 2.4 on your early 3.0 should you choose to do so:

The cam carrier, the chain housing, the cam, and all the associated stuff - chains, gears, tensioners, rockers, rocker shafts. Also the oil pump and intermediate shaft and all the gears associated with that. And the oil cooler.

Plus the valve covers. The intermediate shaft end plate. The crankcase breather piece. The various sensors (idiot, oil p, oil T). The case through bolts and nuts (maybe you could not use the thick washers, as then need a beveled outer edge), except, I think, for the nuts for the two bolts which stick out (as studs) behind the oil cooler - I think this case uses the finer thread through bolts. The head studs, washers, and nuts. The engine and surrounding tin, plus the fiberglass engine cover. The various 6 and 8mm nuts and washers and odd bolts. The engine carrier (the assembly that holds the engine to the chassis at the back). Your exhaust system. The alternator and assorted pulleys.

By using your earlier distributor crankshaft gear you should be able to use your distributor (you can just measure the width of the hole the distributor fits in to see if that part is compatible - I don't remember when the distributors got fatter in the shaft area) if the early 3.0s were the start of the "reverse rotation" system the SCs used.

What you can't use are pistons, cylinders, or (unless you are making a wierd motor and are willing to spend a bunch of money, and you say you are not making a weird motor) heads. You could use the springs and their associated hardware from your heads if you purchase raw heads, but not the 2.4 heads themselves.

Although the bolts will line up, you can't realistically use your 2.4T induction in terms of physical compatibility because the injectors on the T are inserted into the heads, and any heads you will buy won't be set up for that.

Your flywheel will be fine if in good shape, but the junk donor 3.0 you might purchase will have a 9 bolt flywheel that you can't use.

Now how much of this stuff you will want to use is an entirely different story. You might want a larger oil pump, like the ones from '77 on as a minimum, especially in a hopped up motor. You might not want to mix and match case stud thread pitch (I sure didn't). You might want to use the SC and later cams and cam carriers because they have 4 bearings and journals of a larger diameter. If the T didn't use the nice exhaust where each side has a 3 into 1 collector which then heads directly back to the muffler (no crossover), that exhaust won't be for you (and for that matter, if you build a 3.4 even the good early exhaust is probably too small).

I'm sort of in your boat (or was - I'm beyond the decision point now). I bought one of these early 930 cases and a 66mm crank as a start on a 2.8. I had bits and pieces from a blown-up early motor and several others. When buying all but one of the case through bolts from a junkyard for $100, and then laying out the better part of $40 for the one they were short plus its hardware, I wondered if I wouldn't have been money ahead buying a junk 3.0. That would have gotten me the heads and cam carriers as well plus a cam and a bunch more stuff.

And of course many folks would not be caught dead reusing nuts and bolts even though only rod bolts and flywheel bolts are on the bottom line must not reuse list.

But I bought Pauter rods and J&E pistons, and will have used 3.0 cylinders nikasiled (alas, the ones I had are Alusil, which adds extra cost to convert to nikasil). I'd have no use for the 3.0 induction. I have some mag chain boxes which should work fine (they do on my aluminum case 2.7 race motor). I was not going to use an SC oil pump and have no need for an oil cooler. So I've quit kicking myself for not going that route.

I suppose if you can trade your 2.4 for a 3.0 (one would think you might be able to sell a good running 2.4, even the not so desireable T, for more than a non-running 3.0 will cost) that might put you money ahead because you will get the top end stuff you need. On the other hand, if you scavange your 2.4 for parts, the case might bring a decent dollar - it should be the most desireable of the 7R mag cases: it is nicely broken in, but because this is the least stressed of these cases (as a T) it is the best for a project motor using that case (as in, for instance, a long stroke 2.8 race motor)

Those are my somewhat lengthy thoughts on your situation.

Walt Fricke
Old 09-02-2005, 11:13 AM
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