Camshaft for 408C daily driver

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wrobinson

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My Car
My 13 year old wants to build a 1971-73 Mach 1 Mustang for his first car. We have found a Grabber Blue with white interior base model 1971 Mach 1 to start on.
I would like suggestions on a hydraulic flat tappet camshaft for a 4V 408C build that will primarily be a daily driver. The compression ratio will be around 9:1-9.3:1. The car is equipped with A/C, power steering, and power brakes. The rear gear ratio is 3.50. The transmission will more than likely be a non electronic AOD. I would like to shoot for 375-400hp and 375-400tq. The most important thing is idle quality for fuel injection, A/C and vacuum PSI for power accessories

Other information:

Heads are 4V D3ZE with 2.07 intake and 1.66 exhaust Ferrera valves, Crane pedestal conversion kit, and Comp Cams roller rockers.

Intake will be either a Blue Thunder, Scott Cook or Eddy RPM dual plane.

Induction will be an EZ EFI or FiTech system.

Please understand this build is for my 13 year old sons 1973 Mach 1 Mustang.

Some cams I was looking at: Comp Magnum 280, Comp XE274

 
I won't suggest a cam. A cam company will almost always do better than I will.

I will question the compression ratio. Compression is essentially free power. Properly set up a 10:1 engine is not difficult to manage on the street. 11:1 is even manageable. at 11.5:1 my 393 does fine with just premium and a couple gallons of 110

I get that a 13 year old will be driving, but compression comes from parts selection and block machining and is really the closest thing to a free upgrade during a build. Select a mild roller cam and break in and lobe failures will drop to near zero. Roller lifters can be used on a second cam without a problem so the extra cost of lifters won't be a big deal if you dtart off with an RV cam and then graduate him to a higher performance cam in the future.

 
I really like the Howards Street Force 3.

LSA 112, advertised duration 279/289, @ 50 duration 225/235 with 536/542 lift

The wide LSA will help idle quality and vacuum. I think it would be a good starter camshaft for a young enthusiast.

 
I agree with Jeff on both higher compression and a hydraulic roller cam. With a 408 I would stay at or below an advertised duration of 280°, even though the 408 can do well with a bigger cam, for good street manners. This spreadsheet will let you play around with different parameters and help get you in the ballpark, so when you talk to the cam vendor you'll have a better idea of where you want to go:

https://www.7173mustangs.com/thread-camshaft-selection

And, this one will give you some ideas on how various components affect your engine build:

https://www.7173mustangs.com/thread-engine-and-compression-calculations

 
I won't suggest a cam.  A cam company will almost always do better than I will.

I will question the compression ratio.  Compression is essentially free power.  Properly set up a 10:1 engine is not difficult to manage on the street.  11:1 is even manageable.  at 11.5:1 my 393 does fine with just premium and a couple gallons of 110

I get that a 13 year old will be driving, but compression comes from parts selection and block machining and is really the closest thing to a free upgrade during a build.  Select a mild roller cam and break in and lobe failures will drop to near zero.  Roller lifters can be used on a second cam without a problem so the extra cost of lifters won't be a big deal if you dtart off with an RV cam and then graduate him to a higher performance cam in the future.
Jeff,

I know what you are saying about compression. I am actually setting the engine up without zero decking and with shaving the heads. Later on if my son wants to turn it up we have room to do so without changing a lot of components. A hydraulic roller or solid roller are great performance pieces that can be added at any time when he is ready. I am going with the stroker because standard stroke cranks are at a premium not to mention hard to find. Case in point Clegg has a .010/.010 4MA crank for $255. The core charge is $144. Shipping is another $50. After it is all said and done you have almost $500 in a stock stroke crank. A low end stroker kit costs a little more than double that.

 
I saw your new post when I posted mine. Yes, that should be a very nice cam, but really should have a higher compression ratio to make it work well.
I can bump the compression to 9.5:1 by taking .020 off the deck, .020 off the head, and a cometic head gasket. I am just worried about detonation with crappy gas and D3ZE 4V OC heads. I know my son will put the junky 87 octane in it from time to time. You know what I mean. The EZ EFI or FiTech system will help too.

 
That cam should bring the dynamic compression ratio down enough that occasional low octane fuel won't bother it much, especially at 9.5 CR.

The biggest reason for a roller cam is not performance, but is for longevity, and means not having to use racing oil or zinc/ZDDP additives in the oil. Using regular oil has a high likelihood of wiping off a lobe or two on a flat tappet cam.

 
That cam should bring the dynamic compression ratio down enough that occasional low octane fuel won't bother it much, especially at 9.5 CR.

The biggest reason for a roller cam is not performance, but is for longevity, and means not having to use racing oil or zinc/ZDDP additives in the oil. Using regular oil has a high likelihood of wiping off a lobe or two on a flat tappet cam.


Sent from my XT1635-01 using Tapatalk

 
Tapatalk and I are not working well together

I'd build it withe the machine work done and use a thic set of cometic head gaskets to bring the compression down if you feel that is best.

With an aftermarket crank, having your block milled for a 1 piece rear main seal would be a great idea as many of us have had leaks with the scat and eagle stoker cranks

 
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