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I have a 72 chev p-u. it has a 355 with a very healthy solid lifter cam, dont know the specs, also has headers, hei , high-rise dual plane and 194 camel hump heads. i need gears and conv for this cam. my question is how much gear? it has a 700 r4. it is stree driven. i dont like loose converters. i want just enough to make the cam happy. and make the combo driveable and live on the street. would a 410 with the over drive be as good as it sounds. seems like a low gear and overdrive, would be having your cake, and eating it too. Thanks.
 

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I have a 72 chev p-u. it has a 355 with a very healthy solid lifter cam, dont know the specs, also has headers, hei , high-rise dual plane and 194 camel hump heads. i need gears and conv for this cam. my question is how much gear? it has a 700 r4. it is stree driven. i dont like loose converters. i want just enough to make the cam happy. and make the combo driveable and live on the street. would a 410 with the over drive be as good as it sounds. seems like a low gear and overdrive, would be having your cake, and eating it too. Thanks.
The 4.10 gear will give you a 2.87:1 ratio in OD. OD won't be much use unless the road speed is up there pretty good because a cammed up SBC 355 will want to spin, not lug.

But the rear gear is a separate deal from the TC. You want a higher stall rpm so the converter doesn't pull through the brakes when stopped in gear and so you'll have a better idle. This is true regardless of the rear gear ratio.
 

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gear ratio depends on application of vehicle. I use 3.5 gears and I have o/drive.At 60 mph Im just over 2,000 rpm,and the engine is happy. Converter really depends on application of car(truck) a loose converter is for racing.You need a converter that allows your engine a little slip for sport driving if your cam is bigger. without know what your cams specs are,its a random guess.
1800 stall should work,and thats close to stock.You didnt list any wild parts,,,,
 

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Discussion Starter · #4 ·
it does want to rev

it sure likes to rev, it ok on take-off, but comes into its own when the r,s are up. I think changing the cam is a good idea. I love the sound but reving to 5 plus grand is not working on the street. who wants to wate for that many revs. I think a smaller cam is in order. What would be a good one for a heavy truck with my combo
 

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I have a 71 c-10.. mine has 3.08 gear gears..

I'd change your cam to a 270-280 ish hyd.. it'll be a ton more fun..
work better with what's in the truck..
my long bed is 3950. lb not really all that heavy..
adding 4:10 with no weight over the back, tho fun.. doesn't make the truck fast
 

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It would be easier on your wallet to install a cam like the Comp Cam XE262H. Even with this small cam a 1400-2400 stall converter is recommended. The engine output with this cam will be around [email protected] rpms and 395 lbs [email protected] rpms. Here is some information on the GM 700R4 transmission. 700R4 Transmission Swap - SMOKEmUP.com
Nothing meant against Mr. Minter, but I despise those extreme energy camshaft profiles and feel that they are equally as responsible as the lack of high-pressure lubes in off-the-shelf motor oils for roaching flat tappet lifters.

Many years ago, Harvey Crane coined the term "hydraulic intensity" to identify the difference between duration @0.050" tappet lift and duration @advertised. He used 56 degrees on all the grinds I have examined. In other words, 280 degrees advertised, 224 degrees @0.050" tappet lift as an example. Today's extreme grinds from Lunati and Comp, for instance, use a difference of 44 degrees. In my humble opinion, you can use a softer hydraulic intensity (56+ degrees) and have pieces last longer instead of yankin' the valves open and puttin' all that hydraulic intensity at the interface of the lobe and lifter. If you think you will need the additional 10-15 hp that an extreme grind will get you, then re-design your motor with an added 1/4 point of compression and a little more duration @0.050".

Now, I understand the reason for using a high hydraulic intensity in.....maybe in class racing where you might be limited on the 0.050" duration of the cam and have a need to jerk the valves open quickly, but for Ricky Racer out there who runs his motor 95% street and 5% drag strip, there is no justification for a high hydraulic intensity.

The Comp cams that are a copy of '60's muscle car cams have a hydraulic intensity of 120 degrees. That's how the factory did it, years ago. Easy up, easy down.
 

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Techinspector1, You didn't hurt my feelings. Thanks for the useful information on the cam profiles. I knew the Xtreme Energy cams open and close the intake valves faster because of more exhaust duration but I didn't know that they were that bad.
 

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Cranes are measured at .004`lifter rise and comps are measured at .006``
Not entirely true. Crane uses both, depending on the grind. I appreciate your point, but the point I'm trying to make with all this is that the average Ricky Racer street motor does not need the radical "end-all" "yank-em-open, slam em closed" camshaft in his motor and would be much better off with a slower action.
 

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how many guys have ran an XE cam with either face oiling lifters or a grooved lifter bore and had failure problems? just like with solid cams increasing the oil supply will help immensely. Also, how many guys have tried these cams with beehive springs and a lighter retainer and/or valve?

There's a lot more to a valve-train than lobe intensity.
 

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none of the Crane hyd cams are speced at .006" lifter rise.

.004" or .0042" is common for the Crane Hyd cams.
On some the advertized seat duration check spec is not stated at all.

i have never seen one with a published .006" spec.

But of you really want to know you can call Crane Cams tech line . They do kn ow and can tell you
what the cam duration at .006" lifter rise is. (There is a typical approx 8deg difference)
Or you can measure it yourself when you degree in the cam in the motor.

If you want to see how a comp cam stacks up when measured at .004" you can do that too.
When measuig at .004---.006" you must be very accurate with the dial indicator and degree wheel.
But you will see....for your self and now can make a valid comparision.

You do have a valid point in that many many people bite off more than they can chew.
By buying the latest fastest action cam for their street car that will see way more idle time and operation at less than 3000 rpm than it will ever see a rpm that can actually benefit from a XE or voodoo cam.

I like the Crane HMV designs, for a lot of reasons. When you make a really good wheel, you don't need to re-invent it every week.
Comp and Crane and most other big box cam companies use adv. durations that vary all over the place (measuring point)- and many times its not published as such. Also, because its not published as such many times their own tech line can't tell you that.

Don't ever think that not having something published to the contrary means you're correct in your assumptions.

I believe Isky, and Schneider, and Jones, and a few others are all consistent when they give adv. numbers but I could be wrong about that.
 

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I had no problem getting the .006" hyd cam duration specs from Crane.

It's an eye opener.

I believe Isky uses .007" on some hyd cams. Some Isky have a different spec or the opening and closing side. Another eye opener.

You are tying to compare apples to oranges unless you sue the same check spec

The Isky Hyd Mega Cams have a very intense fast lobe design yet again you do not see the cam lifter failures.... Quality counts.
isky lifters fail,, I've never had any luck with their lifters
 
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