Cam Ideas for 413

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hpmopar

hpmopar

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This is a 72 Truck engine with head casting 4006452, it was 8:1, I don't know how the heads would effect the compression
It is mated to a 4 spd and 3.55 posi.

Any cam ideas? I was thinking 474 MP Purple shaft. Would you change the valve springs?

Originally I was going to change the intake to an Edlebrock Performer RPM and add a Holley 750 vacuum secondaries and electric choke

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You will need to change the springs if you run anything more then a small RV cam. The stock HP springs with damper should get you to 6000 RPM with the right cam. I would probably replace those exhaust valve rotators with standard retainers too.
 
IMO, I think the purple cams duration at .050 being 238 is to large for a low compresion engine. Though, through sheer cubes, the effect will be minimized as vs a low compresion 318, you can still do better with a cam selection.

I would look for a split duration cam so it can help out the not so great flow abilty's of the stock head. Here's some examples;

Crane cams;

This cam has a wide centerline @ 112 to help build cylinder pressure in low compresion engines. Excellent daily driver with good power and mileage.
I used this cam before and currently.
http://cranecams.com/?show=browsePa...-440 C.I.&partNumber=643941&partType=camshaft
This one is similar but with alittle more RPM. Could use a bump in the ratio;
http://cranecams.com/?show=browsePa...-440 C.I.&partNumber=643801&partType=camshaft

Lunati cams;

Same , like description as the Crane cams above but without a wide centerline and will have a chop in the idle.
http://www.lunatipower.com/Product.aspx?id=1578&gid=287
http://www.lunatipower.com/Product.aspx?id=1579&gid=287

A summit racing cam, ground by Crane to there specs, similar to a Crane cam. (Cheap!); http://store.summitracing.com/partdetail.asp?part=SUM-6400&autoview=sku

I'm having problems opening anything up from Comp Cams, but they have a XE line that will work very well. Look for intake durations starting at 218 @ .050 or so but under 230 @ .050.

218 @ .050 will have a strting RPM power band of approx. 1800 depending on the grinder.

Given the low compresion ratio, if you go bigger, it will make the bottom end soft and slugish without a big bennifit of a superior top end worth the off set.

Also, I would do the RPM and 750 carb. Just take the time to tune it up and dial it in as best as you can. She'll move well.
The biggest thing your missing is head porting and a good bump up in ratio.
 
Before considering the cam, you are going to rebuild this engine right, she's got a lot of rust in her and those rocker arms have got a huge gap between the rocker shaft and thru hole. I wouldn't go any larger than the MP cam you're looking at and yes to new springs and dampeners at the very least. The 452 heads are a good flowing head for mild street use but you'll really need to find for sure the comp. ratio before nailing down the cam.

Terry
 
If I had REAL cash available, I just buy a 440!
I was originally just pulling the intake to replace the old cast intake and my Carter that is junk (needs a good rebuild)
A friend had the 750 that was litterally new for a hundred bucks.
I figured a good intake and that was it for now. but the motor was seeping a little oil, so I started tearing the front down to replce the timing chain cover..

Now I am here!
 
This is the cam from the 72 413 truck engine HT 413 3-10-72
Any ides on what size it is
I looks like the end of the cam is stamped 920379.

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rumblefish360 said:
IMO, I think the purple cams duration at .050 being 238 is to large for a low compresion engine. Though, through sheer cubes, the effect will be minimized as vs a low compresion 318, you can still do better with a cam selection.

I would look for a split duration cam so it can help out the not so great flow abilty's of the stock head. Here's some examples;

Crane cams;

This cam has a wide centerline @ 112 to help build cylinder pressure in low compresion engines. Excellent daily driver with good power and mileage.
I used this cam before and currently.
http://cranecams.com/?show=browsePa...-440 C.I.&partNumber=643941&partType=camshaft
This one is similar but with alittle more RPM. Could use a bump in the ratio;
http://cranecams.com/?show=browsePa...-440 C.I.&partNumber=643801&partType=camshaft

Lunati cams;

Same , like description as the Crane cams above but without a wide centerline and will have a chop in the idle.
http://www.lunatipower.com/Product.aspx?id=1578&gid=287
http://www.lunatipower.com/Product.aspx?id=1579&gid=287

A summit racing cam, ground by Crane to there specs, similar to a Crane cam. (Cheap!); http://store.summitracing.com/partdetail.asp?part=SUM-6400&autoview=sku

I'm having problems opening anything up from Comp Cams, but they have a XE line that will work very well. Look for intake durations starting at 218 @ .050 or so but under 230 @ .050.

218 @ .050 will have a strting RPM power band of approx. 1800 depending on the grinder.

Given the low compresion ratio, if you go bigger, it will make the bottom end soft and slugish without a big bennifit of a superior top end worth the off set.

Also, I would do the RPM and 750 carb. Just take the time to tune it up and dial it in as best as you can. She'll move well.
The biggest thing your missing is head porting and a good bump up in ratio.
Click to expand...

I appreciate the help, I am trying to stay on the less expensive way to go; without being stupid!
 
The smartest way is to get the whole kit from any grnder/seller of the cam. Sumit has the least expensive cam and getting the cam and lifters with the valve springs is the way to go.
 
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