cygnusx1 Posted March 8, 2005 Share Posted March 8, 2005 http://www.motormeister.com/suz/911_engines/911_engines.htm Read the last line.....? Quote Link to comment Share on other sites More sharing options...
yo2001 Posted March 8, 2005 Share Posted March 8, 2005 early 70's crank was weaker than the later ones due to lack of couterweights I think. The L6 crank goes to harmonic somewhere in the 7500rpm also. Quote Link to comment Share on other sites More sharing options...
speeder Posted March 8, 2005 Share Posted March 8, 2005 I think this guy is still pi$$ed about the 240Zs kicking 911s' a$$es in SCCA C Production back then. Curious that he's still talking about Zs after 20 years or so - Sounds like a deep seated trauma . Probably cheaper (and easier) to rebuild Z motor 8 times than to do a Porsche once. I'm a former 911 owner ....... Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted March 9, 2005 Share Posted March 9, 2005 LOL Speeder ... deep seated trauma... i agree the way the guy writes it sounds like he has some personal beef Quote Link to comment Share on other sites More sharing options...
Guest JAMIE T Posted March 9, 2005 Share Posted March 9, 2005 Just another case of some guy living in the past. He's still pissed off 'cause some guy handed him his a$$ back in the day! Quote Link to comment Share on other sites More sharing options...
mjfawke Posted March 10, 2005 Share Posted March 10, 2005 He's right, actually. The 69-70 crankshaft (not fully counter-weighted) used to shake the clutches apart and were very unreliable. But even the fully counterweighted cranks used to be changed after each race because the would bend. The factory race teams would run qualifying with the crank from the previous race, then would put a new crank in before the race... So - Nissan used to win, but they had a very short life on some of the engine components. Quote Link to comment Share on other sites More sharing options...
Guest 240zJake Posted March 10, 2005 Share Posted March 10, 2005 But what does that have to do with his ability to rebuild a Porsche engine? Quote Link to comment Share on other sites More sharing options...
rudypoochris Posted March 10, 2005 Share Posted March 10, 2005 why is my crank okay after 30 years..... and why didnt they simply counterwieght it if it was nissan's racing division? hmm even if u change the crank on a 240z its still fuinny to see an over head cam beat the tar out of a 911 air cooled 4 cam Quote Link to comment Share on other sites More sharing options...
preith Posted March 10, 2005 Share Posted March 10, 2005 He's right, actually. The 69-70 crankshaft (not fully counter-weighted) used to shake the clutches apart and were very unreliable. But even the fully counterweighted cranks used to be changed after each race because the would bend. The factory race teams would run qualifying with the crank from the previous race, then would put a new crank in before the race... So - Nissan used to win, but they had a very short life on some of the engine components. What I don't get is why is this not an issue now? There are plenty of GT-2 cars here in the states that are putting out healthy amounts of hp, and I never hear of this. One guy who I know very well, used to prepare a CP car in the late 70's/early 80's. It was dyno'd at over 300hp, had a bone stock crank, and they regularly rev'd it to 9500. When Malvern was still around he told me they had problems with the crank actually breaking apart (not bending), but this was solved with a Tilton dual disc and dampner up front. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted March 10, 2005 Share Posted March 10, 2005 He's right, actually. The 69-70 crankshaft (not fully counter-weighted) used to shake the clutches apart and were very unreliable. But even the fully counterweighted cranks used to be changed after each race because the would bend. The factory race teams would run qualifying with the crank from the previous race, then would put a new crank in before the race... So - Nissan used to win, but they had a very short life on some of the engine components. Well that's it. I am selling my 70 Z and buyng a Porsche. Quote Link to comment Share on other sites More sharing options...
johnc Posted March 10, 2005 Share Posted March 10, 2005 When Malvern was still around he told me they had problems with the crank actually breaking apart (not bending), but this was solved with a Tilton dual disc and dampner up front. Exactly. The later cranks were (are) fine. What was needed was a better way to dampen the harmonics. The early CP racers were stick with the stock harmonic balancers which weren't up to the task of constant use at rpm levels above 7,000 rpm. Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted March 10, 2005 Share Posted March 10, 2005 What does that last sentence have to do with the rest of the page? It'd be kinda like me goin on talking about the war in Iraq and then at the end saying did you know that "Washington crossed the delaware in a boat?" True or not how does it tie in? I keep tryin to figure out how this ties in to the rest of his statements. Like somehow that has bearing on what ever else he was talking about. Unless he is trying to make an excuse for how often his motors need rebuilding by pointing out one that was weaker. (I don't know enough about either motor to say factualy.) All I know is what I heard. That is, in it's classs, the early Zs beat the pants off everyone else. And it ran mostly stock. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted March 10, 2005 Author Share Posted March 10, 2005 .... talking about the war in Iraq and then at the end saying did you know that "Washington crossed the delaware in a boat?" .... ROFL They needed new paddles after every crossing. Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted March 10, 2005 Share Posted March 10, 2005 ROFL They needed new paddles after every crossing. Realy? I hadn't heard that one. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.