Superman's '83 info has been posted above. I do think Noah's info is worthy of discussion, if for no other reasion than his HP numbers are skewed from anything else I have seen and no logical explanation.

Jim's/Superman's engine and Noah's #s are both recent 3.0 rebuilds and have similar torque numbers. I trust the torque numbers, more than a 25hp jump from a one point jump over my car in compression for example. Although I have been quoted an additional 10hp from each .5 point in compression increase.

The major difference between Jim's and my cars...big and small intakes... is that I am about 500rpm later on the torque curve. But, it is virtually the same curve. And the 10 extra HP of course on my 190K mile engine in comparison to Jim's virtually new one. 10HP worth $2500? Not to me.

I didn't hit my rev limiter on the dyno at 6900rpm. I would be interested to know if Noak did. Hard to tell what the cars are really doing for power unless you can see the numbers drop through the entire rev range.

Dave, my graph is the last one in Dane's last post on Page 1 ("above" I guess you could say). I guess I'm still a bit hazy on what "horsepower" is, but I think it is essentially a mathematically derived number using torque and rpms. According to my hazy understanding, an earlier SC will make more HP than mine by shifting the torque curve up in the RPM range. That is, the more torque you can make above 5250 rpm, the more HP you will make. I really don't think there's that much difference between how the early SCs will react to modification, unless you try to pack better HP at higher RPMs. If you do that with a later SC, you will not get the excellent results you could get with those same mods on an early SC.

So, Jim, provided that you make it sound like enlargening the heads along with the intake runners (and airbox), is worthwhile provided 20/21 cams are installed. But upon reading your post again, I'm not sure what you mean by "better HP."

Dane states that the only true difference between an early SC and late SC engine with 20/21s is that with the late motor, develops its highest hp and torque numbers 500 RPMs earlier. If a 500 RPM delay is all I'm going to get with large bore intakes and heads, I could better spend my money on a cruise ship. :D

I'm certainly no expert but I think what makes a difference are things like, Noah's light crank, my light flywheel to a lesser extent and even more so, fresh engines like Jim's and Noah's producing all the torgue that is available from a 3.0.

Looks to me by the limited dyno samples I have collected that as long as you back date your exhaust in any form (buy cheap, not brand name IMO) you'll pick up darn near the same HP.

20/21 cams do make a more drivable engine. Jim's torque comes on earlier, making it even better as a everyday driver I would think.

Noah's has a bit more HP and torque that is as good as we have seen. It should be a very nice street machine. My only concern are the peaks on the torque...in comparison. I suspect that is the engineering. As the 20/21 is a specific performance grind.

But on the plus side the 964 cam didn't "die" at 5500rpm either. If that is the performance curve on a 964 then it has some real advantages over a 20/21 depending on your needs.

I am tempted to do a bunch of little tuning tricks as I rebuild my 3.4 engine just to see how far I can take the CIS. CIS is easy as a everyday driver so I am sticking with it.

But if it weren't for the need to do a valve job, I wouldn't go past where my engine is now. My intent on my rebuild is to just bump up the torque and HP while making the engine even more bullet proof than the original for the next 200K miles.

Lightening up that 3.2 crank and add some Ti rods should make up some HP;)

For what it's worth, I spoke with Steve Weiner about the small port/large port SC thing. His opinion is that unless you are using a "real cam" not a wimpy CIS compatable one, it won't make that big of a difference, and even then only up high.

Tom

Tom: that's what I'm starting to realize. Thanks for the insight.

Considering my revised Reseda dyno measurement of 193, and Jim's 198, I think the 5hp can be made up in headers or SSIs.

NOTE: you guys do know the port size for '74 heat exchangers is smaller than Bursch headers or SSIs. Plus the headers are 10 pounds less weight than exchangers or SSIs.

Torque curve is another interesting factor. Jim's lasts (I think) 1000 RPMs longer than mine. What does this mean other than at WOT, I'm not sure, because...

I've also got the lighter weight and the 7.31 r/p.

Now, can weight and a smaller r/p somehow make up what I don't have in 20/21 cams?

Jim was running a pre '74 exhaust and I have SSIs. I think any pre '74 system will give you 5HP or more if you haven't done that yet. Factory headers and super traps would be fun if you didn't need heat and drop more weight yet ;)

Glenn's '81 had SSis and ran 159rwhp/ 169 torque at the rear wheels. Marks' '79 with stock heat exchangers and a Flowmaster off BBI ran 168 rwhp/161 torque. Your car running 164rwhp and 167 torque is right in there imo.

Jim's numbers are 173rwhp/174torque. Total mods are '73 OEM exhaust, triad muffler and 20/21 cams and the most obvious recent rebuild.

I have to think pre '74 exhaust and a free flowing muffler would be the best add ons. More importantly I suspect a stock engine ( having a recently refreshed engine wouldn't hurt either) would be better served with a new set of fuel injectors and a good tune up. Best $1000, or less, you can spend on a CIS car I bet.

I'll add SF lube to much of my pistons and then new injectors. Once the engine is apart I think it'll be the details putting it back together that make the difference between an OK engine and a really great engine. Those details are pretty much the differences between a Porsche factory race engine and a production engine.