[glhs#116]

OK, so let's just cut to the chase. Let's say a guy had a fairly stock 1971 455 HO engine with the 197 heads and the RAM AIR manifolds and HO intake and 71 455 (though not "HO") carb. Let's assume 3.42 gears and automatic (with future plans to go manual) equipped 1971 Trans Am with no weight reduction. Given all I'm reading here what realistically prevents me going from my 068 to the Old Faithful grind? I'm not seeing much downside and it looks like there should be some good upside!

Also, as a complete non-initiate into the whole Pontiac cam world, what is the Old Faithful grind and where would you get one?

Lastly, I guess my main concern would be that I wouldn't want the car running hotter at idle than it does. I have a big aluminium radiator but I also have to drive half the year in heat and humidity you guys would NOT believe.

Thanks in advance and loving the thread!

Sam

[72LuxuryLeMansLa.]

Originally Posted by glhs#116

OK, so let's just cut to the chase. Let's say a guy had a fairly stock 1971 455 HO engine with the 197 heads and the RAM AIR manifolds and HO intake and 71 455 (though not "HO") carb. Let's assume 3.42 gears and automatic (with future plans to go manual) equipped 1971 Trans Am with no weight reduction. Given all I'm reading here what realistically prevents me going from my 068 to the Old Faithful grind? I'm not seeing much downside and it looks like there should be some good upside!

Also, as a complete non-initiate into the whole Pontiac cam world, what is the Old Faithful grind and where would you get one?

Lastly, I guess my main concern would be that I wouldn't want the car running hotter at idle than it does. I have a big aluminium radiator but I also have to drive half the year in heat and humidity you guys would NOT believe.

Thanks in advance and loving the thread!

Sam

Your heads will need new valves and machine work to handle the lift associated with a cam like Stump Puller or Old Faithful. Dave at SD would be the man to consult since he picked the lobes for those cams and knows what the heads need to use them. It is easiest to contact him through the email links on his site: http://www.sdperformance.com/viewPro...productID=1816

[ponyakr]

"Probably be pretty similar. Rule of thumb is that Rhoads shave off about 8-10 degrees of duration at idle."

"I would expect both to be close to the same. Given the choice I'd opt for the RAIV cam with Rhoads lifters."



Isn't this amazing ?

After many pages and over 225 posts about 455 cams, with some refusing to even offer any specific cams, without EXACT minute details of the combination, at least one saying they had a bad experience with Rhoads lifters, some saying go roller, and LOTS of other ideas, we're right back to the 041 / Rhoads combo.

It seems that some guys will hold out for "new technology", regardless, thinkin it has to be better than that stuff that was designed nearly 50 years ago. Even after all the drag strip testing done by Jim and Cliff, well documented for all to read, proving that the 041 / Rhoads combo is hard to beat, many just simply refuse to accept it. These 2 guys have probably done more testing with the 041 / Rhoads combo than everybody else on this forum combined.

So, my conclusion is that for a STREET driven(mostly 600-5000 rpm range) hyd flat tappet cam, the 041 / Rhoads may just be the best combo available for MANY 9:1 CR & up 455-474 cube engines.

For those who may not have read it, Jim tried several cams that were real close to the 041 specs, and discovered that none of them were quite as good from idle to his shift point as the 041 / Rhoads. Those that made just a hair more top end, wouldn't idle quite as well as the 041.

And, since the 041 / Rhoads will idle so low, for street cars with hard street tires, you don't even need to buy one of the high dollar converters. This combo idles smooth at 800rpm or lower, has instant torque, from the 1st stab of the throttle, and will pull strong to past 5000rpm. Unless you will accept nothing less than 500-600hp, my question is, what else could you ask any HFT cam to do ? Will any of these other HFT cams that have been mentioned, idle as smooth and low, with good vac, as the 041 / Rhoads, AND still have as much or more top end power ?

So, if you are planning a mild 455 / auto street build, and have never tried the 041 / Rhoads, try it before you bad mouth it. Then, if you don't like it, at least you'll have something to compare your next cam to. And you can report back about what cam / lifter combo you used that was actually better than the 041 / Rhoads.

If I'da said this much on the site I got kicked off of, they'da crucified me and set fire to the cross. But at least here, I have Jim and Cliff's testing to back me up.