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[B]who can help me?[/b] I have a 1971 240z. I had to bore it three over and I had to deck the block two down.In the block I have flat top pistons. I'm also installing 280Z vales in my E31 head. And I plan on putting a header on also. Other than that every thing is stock and I plan on keeping it that way. So what cam do you advise me to get. MSA's third package sparks my intrest but some say that it will make you slugish out of the hole. But a guy at MSA tolled me to get six pounds shaved off my fly wheel and it will fix the problem, is this true and how much will it help. I'm not looking to make a total race car, but just Excellent street performance. And I am also woundering how to figure out the compression ratio on my car. I have the formula but I'm stupid :stupid:. Also just how ruogh does the third cam idle, could you give an example of what it sounds like an what muffler would you advise. I'm sorry to ask so many questions but these are the questions that no one can answer in this town. SOME ONE PLEASE HELP ME!

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I think better advice would be leave the stock cam(don't forget changing the deck height will mean you have to add shims to keep the valves out of the pistons' way (n.s. w/280 valves), add the header and a larger exhaust, port and polish the head, port the intake manifold to match, and rebuild/rejet your carbs, and keep the car tuned.

Lightening your flywheel makes for a car that is more difficult to drive on the street (Lowering the moment of inertia on the clutch drive does mean the engine can rev up faster, but it also makes it harder to drive smoothly because there isn't as much energy stored in then movement of a lighter flywheel-meaning the car is much easier to stall-especially in hills/mountains)


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I don't know what the MSA style Camshaft is like but I'd say it would be fine if you don't go over the top on porting. It's a combo of both porting and camshaft profile that would make it less drivable down low.

I'd say you'd be fine with the wild cam but if your not going to do much else to the motor it's kind of a waste. As Will was saying you'd be better off spending your money on the items he listed and if your not happy then put in a bigger camshaft.

Can you give me the formula for C:R? I've never seen what it looks like and would like to know how to work it out myself aswell.

I have a lightened flywheel in my Z from memory it's about 6 kilograms that's prob ~12pounds in your measurement :P.

I find it quite reasonable sometimes when the motor is cold the revs drop very quickly and it can almost stall but i tinker with the choke anyway. I find it can be a little sensitive on the throttle but that's also because of the distributor recurve.

It comes down to your budget and your goal i guess.

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I have a 13.5 LBS flywheel and have never had a problem with it on the street. I do not believe in lightening the stock flywheel, other will say it is fine. IMO if you want a light flywheel buy a light weight one do not try and make your own. If you go too light the car will not be streetable at all. The stage III cam is probably the limit for street driving. I would go for the stage II, you will not have to shift nearly as much, your HP and torque will come on at lower rpms. My flywheel does not really make that much differenct in acceleration off the line or make up in lowend power loss. I got the light flywheel for the feel and ability to rev the engine quickly to match the engine/trans for down shifting. The light flywheel is not realy necessary but I love mine and will allways use it.

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