Where would I go to purchase a cam shaft and solid lifters 65 L76
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Re: engine
Federal Mogul is an OE quality source for replacement camshafts. The original "30-30" cam is available (CS-118R), but I recommend the LT-1 cam (CS-1145R) as it will make better low end torque with about the same top end power. The key to top end power is head flow, so if that is a goal you need to massage the heads.
The 30-30 cam was discontinued by Chevrolet circa 1970 and the LT-1 cam is listed in subsequent parts catalogs as the replacement for all original 30-30 applications.
I believe Dana Corp. also offers replacements under the Clevite brand. Go to napaonline.com and cross reference the above two numbers.
Duke -
Re: engine
If you want your engine to run, sound and drive like it did when new, stick with the original cam. The 30-30. There'll be no confusion when it comes time for service, either. Some like the LT-1. Many don't.
I've never seen a Corvette that hit on all eight cylinders that needed a boost at any rpm.
The exception is the Blue Flame.Comment
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Re: engine
Federal Mogul Sealed Power:
The "30-30" solid cam is their #CS-118R (or KC-118R kit with lifters) - specs are 254/254 duration @ .050", .455"/.455" lift, 114* LSA.
JoeComment
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Re: engine
Sal,
The Federal Mogul piece is an exact clone of the original 3849346 (AKA "30-30") L76camshaft.
We in the NCRS are supposed to be all about restoring our cars to the same state that they were in when delivered. If I were you, I would not substitute an LT1 camshaft. There is plenty in the archives about it, and some are persuasive enough to make a good point in selling it.
There are some dyno numbers available, showing a "more-or-less" straight-up comparison between an LT1 equipped 327 vs. an L76. There were differences in the test car's exhaust systems, states of tune, general engine build quality/health, and weather conditions. All of these variances, combined to make the tests inconclusive. Dyno numbers did not show much torque difference, at all, and, actually showed the 30-30 with higher torque numbers at some points. The 30-30 should, theoretically make more top end power than the LT1 in 2 otherwise identically configured engines. Engine Analyzer, indeed, bears this out. The dyno tests, however, showed the complete opposite, which stands to reason, because the L76, as tested, was later confirmed to have internal sealing problems!
The 30-30 has a distinctive idle cadence that is not quite the same with the LT1. Additionally, if you wish to be able to state, truthfully, that your engine is equipped with the most radical camshaft that Chevrolet ever installed in a PRODUCTION SBC, then build your L76 with its original L76 camshaft. IF YOU KNOW HOW TO DRIVE IT PROPERLY, then you'll be rewarded with a "rush" of top end power that you'll not find with any other production camshaft.
Do you use your vintage Corvette as a grocery getter? Well, then you might consider emasculating it by installing a milder camshaft, like the LT1, or even the L79. If you want all of your torque at the bottom end then consider building your engine as an L75.
When the internal issues with the test L76 are addressed, then I will post the test results, which should once and for all, put this issue to rest.
Joe
JoeComment
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Lift : .485"/.485" *NM*
Comment
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Re: engine
sal-----
You'll probably find that purchasing whichever cam and lifters you decide on through an online source like Summit (www.summitracing.com) is going to get you about the best price you're going to find. You cannot buy these items directly from Federal-Mogul.In Appreciation of John HinckleyComment
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Re: engine
Mark Johnson can't discern any substantial difference in the idle characterisitics of his OE L-76 and after the engine was rebuilt with massaged heads and the LT-1 cam, but it makes a lot more low end torque, and more top end power with useable revs to 7200.
His data and links to other web sites with his data can be found by searching the archives using search word "327 LT-1" and my screen name. IIRC it was about mid-2005.
Your engine's torque/power curves are an anomaly, and you won't find out what's going on until you do a forensic teardown.
DukeComment
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More info
It was mid-2006. The following link should get you to the thread
All the details are on the C2 Corvette Forum link including the chassis dyno test or you can search the Corvette Forum for posts by ghostrider20.
Also Dave McDufford posted extensive details of his nearly identical configuration, which was tested on a lab dyno on both the Corvette Forum (search posts by "Dave McDufford" circa 2003) and Vetteheads.
DukeComment
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Re: More info
I've read all of those results, and you and I have been over it extensively in phone discussions.
I'm very anxious to do a few more dyno runs with my engine once the internal issue is corrected. As you know, I also suspect that my actual compression ratio may be somewhat lower than I had believed. When I do the teardown, I'll be more precise in my measurements, and will aim for an actual, measured/calculated SCR of 11.0:1. Presently, I suspect that mine, as built is actually closer to 9.75 - 10.0:1. This lowered compression will, as you know, kill the output of the 30-30 cam in the upper rev range.
If you remember, my torque readings were actually higher than the LT1 equipped engine, at some points on the low/midrange. If you recall, my engine's torque output began dropping prematurely, at about 4800 RPM. If the engine was in a healthy state, and with sufficient compression, and equipped with a low restriction exhaust system, instead of the highly restrictive sidepipes, then projected power output at 7200 RPM would have exceeded that of the LT1 equipped engine.
The LT1 equipped engine had no "SUBSTANTIAL"idle difference, but that's not to say that a discerning judge, or anybody else with a discerning ear could not easily detect the difference.
The LT1 equipped engine "but it makes a lot more low end torque, and more top end power with useable revs to 7200". The ported heads probably had a lot to do with that result.
The only way to know, for sure, which config will produce which engine characteristics, is to have a valid comparison. Again, Engine Analyzer clearly shows the L76 as producing more horsepower, when all else is equal.
The only way to make a valid comparison, is to have a valid test, where all variables are kept to a minimum. I will be sure that I have my heads flow tested. My goal will be to duplicate the excellent flow numbers of the heads that were used for the LT1 test. I will be sure to dyno test on a day with the same ambient conditions, and be in further contact with you, to gather any other test stand configuration, and sensor placement locations, as was done with your LT1 test. I will conduct my test with a free flowing exhaust system, similar to that which was used on your LT1 test.
It will be interesting to finally see some valid results. Win or lose, I would be willing to collaborate with you in publishing an article in an upcoming Restorer issue.
Stay tuned.
JoeComment
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during the dyno test
make sure the fuel temp is within 5 degrees and the oil temp within 2 degrees to get comparatable results. the oil temp is important as i have seen 18 HP difference between 180 and 200 degree oil temp on a 500 HP engineComment
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Re: during the dyno test
Few cars have oil or fuel temperture sensing and dyno operators typically don't have any equipment to measure fuel or oil temperature.
Many do have wide band O2 sensors that record A/F data, which is very useful to see if your fuel flow map is in the ballpark.
I always look for at least two back to back runs within no more than two percent, preferably one percent. The second run is usually better - probably due to higher oil temperature.
The MOST IMPORTANT thing is to have plenty of external fans and, hopefully test in cool weather in order to keep the fan clutch from engaging.
Mark Johnson had no choice but to test his car on a portable Dynojet 248C and the vendor had no fans. It was also over 90 degrees (The SAE correction factor was 1.06). The engine did not overheat over several runs in both second and top gear, but Mark reported that the fan was "screaming". My estimate for fan loss is about 15 HP from 3500 to 7200.
When the fan clutch is fully engaged, fan RPM is limited to about 3500, so the power loss is close to constant from that point up.
If the fan clutch does not engage, fan RPM is limited to about 1500 and the power loss is about 1-2 HP - big difference!
Fan power absorption increases with the CUBE of fan speed.
DukeComment
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Re: during the dyno test
i am talking about engine dynos as chassis dyno can show a power difference depending on temp of the gear oil in the trans and rear.the hardness and softness of the rubber in the tires and the rear gear ration will show a difference since some gears require more HP to turn. if you are looking for just 10-20 HP and using 2 different cars i would not put much into the accuracy of the resultsComment
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Re: during the dyno test
Few restorers have the budget to do lab dyno tests, which are quite expensive given all the time to set them up.
I have found good correlation between similar engines when tested on chassis dynos and good correlation with Engine Analyzer predictions for net power when using the typical 15 percent driveline loss for a manual transmissions in direct drive. I actually prefer chassis dyno tests since they yield "as installed in the vehicle power" which includes driveline, accessories and exhaust system losses.
A highly tuned engine with a lot of valve overlap that puts out big SAE gross numbers on a lab dyno can see HUGE losses when it's plugged up by a vehicle exhaust system. Lab dyno tests only make sense on a racing engine where the vehicle configuration is essentially the same as the lab dyno test configuration.
For road cars, chassis dyno tests are much more revealing.
DukeComment
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Re: during the dyno test
if they can afford to spend $50K restoring a car $500 a day for engine dyno time is cheap. hell guys spend more that that for restamped parts.Comment
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