[TNCHEVYMAN]

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.

[cobalt327]

Originally Posted by TNCHEVYMAN

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.

[vinniekq2]

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,,,,

[F-BIRD'88]

A lumpy rough idle cam needs a loose converter to idle nice in gear and perform well on acceleration. Good th700r4 converters have a internal lock up clutch
so the converter locks 1-1. big cam get a 3000 +. stall.
Gears will depend on the rear tire height. tall tires needs a higher gear ratio.
Trucks are heavy and need more gear, when cammed up.
Big cammed motors want to rev.

The good th700r4 converters are not cheap.

What is the manifold vacuum at idle in gear?
what is the tire diameter?
A big cam also wants a different distributor timing curve
A stock curve does not work well.

"low gear and overdrive" sounds better than it works. A cammed up motor wants to rev.
Its not happy at low rpm.

Why not just change the camshaft to match the truck/gears/converter and purpose?

[TNCHEVYMAN]

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

[cdminter59]

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 309hp@4500 rpms and 395 lbs torque@3500 rpms. Here is some information on the GM 700R4 transmission. http://www.smokemup.com/tech/700r4.php

[F-BIRD'88]

If you want the OD to be effective and usefull install a cam with a duration @.050" of 203 to 212.

what gear? tire diameter?

[E.Furgal]

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

[prostreet6t9]

[QUOTE=F-BIRD'88;1608223]
Gears will depend on the rear tire height. tall tires needs a higher gear ratio.
Trucks are heavy and need more gear, when cammed up.

You mean "lower gear" Higher numerically BUT lower gear ratio.

[techinspector1]

Originally Posted by cdminter59

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 309hp@4500 rpms and 395 lbs torque@3500 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.

[cdminter59]

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.

[F-BIRD'88]

Originally Posted by techinspector1

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.

this is incorrect. The actual seat to seat timing between a Crane HMV cam and
a exteme energy cam is not that much different.
But: Cranes are measured at .004`lifter rise and comps are measured at .006``
The measured spec is not the same and not comparable.
This makes the seat duration look much shorter and makes the cam seem much more intense,

YOU MUST measure both cams at the same lift spec to compare.
There is a aprox 8deg difference. between a .004 and a .006 speced cam.
When you campare these cams at the same check height they are not that different.
They are different, but not that different.

IMHO the biggest problems with the extreme energy cams is
mass production cam quality control, hyd lifter quality control and PROPER Customer/End user INSTALL.

They sell way more òff the shelf`XE268H-10 cams for SBC`s than they could ever hope to produce in house.
I bet they sell 2 more of this camshaft for SBC's ..... for every other cam they sell for all makes of engines combined.

Probabily most are made for them "outsourced" by the lowest bidder.

The XE cam I run in my 406 was custom made in house, for me.
No problems with this cam. (It is not perfectly quiet at idle)

The old factory cams were measured /rated for duration at .001",,, not .006" or .004"..... big difference.
The old cams had a HYD intensity of around 60-70deg,,,,not 120. When measured at a comparable/same spec.

The crane cam does have a slightly tamer hyd ramp than the comp XE grinds.
The XE grinds do require more carefull break in, (like reduced spring pressure for run in and highest quality hyd lifters) and camshaft manufacturing quality control is critical.

Most of crane HMV catalog cams have wider LSA's If you want one of these cams on a say 106, 108 or 110 LSA
all you need to do is call and custom order it. You will get a good cam from Crane.

[techinspector1]

Originally Posted by F-BIRD'88

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.

[ap72]

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.

[F-BIRD'88]

Originally Posted by techinspector1

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.

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.