Jim,

Pulling one spring would allow you to check the installed height easily. If they are, in fact, your 943s, math takes care of the rest.

I recall some of your problems with the engine builder, and "Someone may not have been very "awake" when they filled it out." is very generous on your part.

Also, a quick check on the one dual spring removed would prove their specs.

You idea of a different cam has merit.

Jon

 

The guys with the Solid Rollers who have posted, seem to all be using very "large" grinds, which wasn't what the thread was started to discuss. We were talking streetable high lift, moderate duration cams.

From everything i've read in this thread, i can't see any real benifit of running a solid roller on the street (using street profiles).

Has anyone done any dyno or 1/4 mile testing or have a comment on SOTP differences between comparable HR vs SR cams??

 

Sounds like a good summary to me.

 

Mark had nothing to do with building the engine, FWIW. B&B Performance did all the machine work, porting, assembly, and dyno runs, and they provided the documentation.

Only if I had a spring compressor with a gauge on it or some other way to test them.

From appearances, they are the same springs I sent down, and the locks and retainers are also the ones I sent. I seriously doubt that any substitution took place on B&B's end. The only substitution happened after things turned ugly and the items that Mark still had in his possession at that time were the only ones at risk.

 

Why? They've only got a few dyno pulls on them, and they're Crower Extreme Duty lifters.

 

Oldsstroker,
I ran my 943 springs at 1.950 as recommended by CC, with my .688/.672 lift SR cam. I never had a problem with the springs. The 406 engine was typically shifted around 6200 with this setup, but pulled much higher than that.

Stealthramman

I ran a fairly aggressive HR cam (.600 lift) before this SR and was very happy with it. As far as valvetrain noise, it was nearly as noisey as some street SR grinds. My heavy car typically ran in the 11.8s with the HR. When I got ready to freshen the engine, I decided to go with the more aggressive SR. I never had my engine dyno'd but by going from a 5.7" rod to a 6" rod and from the HR to the SR my ET dropped from a best of 11.82 to 11.66. The mph picked up from 113 to 116.6. The advertised duration was similar on the two cams (288/304 on the HR, 283/302 on the SR)and they both made around the same vac at an idle. (15.0 for the HR, 14.0 for the SR). As far as the driveability, there really was not much difference between the two of them. The HR would get up to 21 mpg on the highway. The SR got 20.5 on a couple of occasions. In order to see any real gains from a SR cam, you must utilize the more aggressive SR lobes that are available. If you don't, then there isn't a real benefit to running a SR over an HR, IMHO.
Kevin

 

I don't agree with that. Just looking at the profiles of the two lobes should indicate that the valve opens faster and stays open longer on an SR cam. More air and more fuel equals more power, obviously.

I believe that all things being equal, a solid roller will make more overall power, more average power, and with larger cams, be more driveable than a hydraulic roller equivalent. If not, show me the list of people making 600+ NA horsepower with hydraulic rollers...

Even if I drop back to a more streetable SR, I will still be making more power than any hydraulic roller LT1 I've ever heard about. My 260/267 cam didn't ever make a healthy pull because of ignition breakup, but still made 641 hp @ 6,600... and 637 @ 7,400 on the base maps. What do you think was in between if the Opti-spark had been able to get the job done, even without tuning? A 23x-24x range SR cam will still probably make 600+ horsepower in my engine. I haven't seen anyone with a CC306 making anywhere near that kind of power.

 

Two interesting solid roller STREETABLE grinds in the comp. cams catalogue:

268AR 224/224, .525/.525 @ 110

or

XR268R 230/236, .552/.564 @ 110

The notes indicate both have higher lobe lift than their HR counterparts. The RPM range and red line is also significantly higher.

I'd love to see what kind of power these grinds would make compared to their equivalent HR series cams. I'm guessing that either would make more power and the power wouldn't drop off so quickly at the top end.

I was planning to replace my HR lifters with 875's anyways, so the cost difference going to a solid roller wouldn't be much. I'm thinking that these cams could work well on the street??

 

Jim,
I may have said something the wrong way in my last post, but I think that we actually are in agreement.

Let me try to say it in a different way...
I saw a dyno test recently with a roller cam and two different sets of lifters...one set was a hydraulic roller, the other was a solid. Everything else was the same. The average hp and torque was almost identical with both sets of lifters. There was no average hp improvement found by switching to solid rollers.

Back to your statement about looking at the profiles of the two lobes... I think that you're right and wrong about this. I agree that most SR cam profiles are more aggressive that most HR profiles...but not all of them are.

I've built several street engine with SR cams and many more with HR roller cams. I recall a good running torquey 406 that I built several years ago. The cam was an Erson SR street cam. I think that the specs were 278/286 adv dur, 238/246 duration at .050, .555/.555 lift at 108 LS. It was a good little street roller and easy on parts. I could shift that engine at 5200 and run 11.9s at 112 mph. I built the same engine for a different car that weighed the same and had the same rear gear and same stall speed converter. It was built with a street HR cam of the same advertised duration and lift. The car ran almost identical numbers (11.9s).

Later, I took this same engine with a larger HR cam (that was only slightly larger in duration as compared to the Erson SR, but with a much more aggressive lobe...over .630 lift) and ran a best of 11.74@113+ mph. This engine could have made more hp with a more aggressive SR, (which it later did) but it was a very aggressive lobe.

That is an awesome street engine that you've got there Jim. I hope that you get it installed soon. We are ready to see some awesome ETs and mph.

Take Care,

Kevin Winstead
Product Engineer
TCI Automotive

BTW, I'm almost a celebrity now...I found out this week that I was mentioned in a Dave Emanuel article in the April '04 issues of Corvette Fever (p. 64) and Drag Racing Action (p. 85). I also found out today that I'm gonna be on ESPN 2's Inside Drag Racing again. Big Daddy Don Garlits interviewed me at the PRI and they're finally going to air the show on March 7 at 11:00am EST. Ya'll need to get the autographs while they're still free

 

Jim,

I ment when it's time to replace the springs, not no by any means. It was a general suggestion to everyone.

Not always. Total Duration, .050 duration and lift being equal the lobe area measured in sq in deg will be very close. HR and SR ramps (the area where the cam goes from base circle to the flank of the lobe) are pretty dam close.

Both a HR and a SR can be both equally undriveable or driveable. The lifter difference and relative lobe difference is not going to cause the driveablity issues to differ.

No doubt on the high RPM advantages of a SR, but there are HR race motors that tunr 8,000 no problem

600hp with AFR 215's and a HR cam? Easy take out 30 cubes from your 396 and shoot the motor over to Joe Sherman, won the Engine Masters with that setup and made 600hp. With a cam swap I have one in my shop that can do the same thing. 600hp is not that hard to do.

Your A/F ratio wasn't even close either, that motor needs some tweaking on the dyno and it will make even more power.

The big thing is that you have some bad as castings to start with to make that power. That's where it all comes from not from the SR camshaft. A big SR cam like yours and a off the shelf CC306 is more like apples and oranges. How about a HR rules restricted race camshaft that might be a better comparison and will make for about equal HP.

It's a hyd plunger in a lifter for christ sake. That's it!

Bret

 

For your sake, I'd hope not.

 

I've been reading this post and I think I can offer a happy median for your applications. We build a hydraulic lifter that is modified to act like a solid but only require the maintenance of a hydraulic. The lifter is internally modified and is a direct replacement for a standard hydraulic roller. I have them in many street/strip cars, most NHRA/IHRA stockers and also dirt, SCCA, tractor pull, and most other classes that require hydraulic lifters. For more information feel free to e-mail me at shermanracing@eatel.net or call me at (225) 717-1461 or my Dad, Cliff, at (225) 473-4923.

 

To all of you that have broken lifters:

Were you running oil restrictors?

Ryan

 

Ryan

Yes and no on using oil restrictors.

When my first engine was put together, it had oil restrictors and after galling one camshaft we pulled the engine and I removed them. Don’t remember for sure if a lifter had broken then or not. The engine was redone and for sure it did not have oil restrictors and for sure, I broke lifters. Again….. this is changing everything including a different set of heads with obviously different springs.

As mentioned…… I don’t have any answers and the only thing in common is the cams were all custom grinds from Cam Motion.

Galling problem – 236/242 - about .600/.610 lift (no longer have cam card)
Broken lifter – 246/254 - .656/651 lift
Broker lifter – 240/250 - .650/.658 lift
Broken lifter – 254/262 - .668/684 lift (hated the cam for street driving)

So anyway….. guess the only consistent thing is pretty high lift and that’s all I can figure out.

 

Interesting article in the April Car Craft magazine. Project Humble Pie. They got 401 hp from a carb'd 355 and a Gm hot cam. Then they stuck a 280/284 solid roller and only managed 420 hp from an extra 22 degrees duration. It peaked at 6000rpm. hampered, i'm assuming, from the mediocre flow of the stock vortec heads and 9.1 compression.
All in all, not cost effective to only pick up 19 hp...but an interesting article.
I'd like to see them pump up the compression to 11-1, then port the heads. i'm sure they'd see some power with that cam.