A little camshaft advice sought

[mh434]

Hi all
So my block and crank are currently at the machine shop getting ready to be bored, ground and balanced. They are going to drill and tap the block to accept a camshaft thrust plate so I am now looking at which camshaft to get. Dave Dare suggested the following https://www.summitracing.com/int/par...-643/overview/ which looks to be a fairly stock replacement ? If I wanted a bit more low down torque and a bit more noise (nothing too drastic) while retaining a decent idle what would you guys recommend ? Summit sell camshaft kits with everything included, cam, lifters, springs etc, I would be tempted towards one of those.
Any thoughts ? and apologies if this has already been done to death.

Thanks

Jon

[pbf777]

The camshaft listed would make a fine stock replacement unit, but perhaps, if one wishes a bit more spirited ride, may find it somewhat boring.

Assuming your vehicle is currently of a stock configuration, with the 352 FE, although rebuilt otherwise unmodified, C.O.M. transmission and original gearing in the differential, I would suggest adding (to the example presented) a minimum of 8 to 10 degrees of duration but not greater than 15 degrees, for in excess of such one would be getting a little "hot-roddy".

As far as buying the "complete kit, with everything you'll need", communicate with your machine shop reworking the cylinder heads for their recommendations, as they can (should) establish the proper set-up particularly in the way of the valve train (springs, retainers, locks, shims/cups, seals, etc.) components. I recommend this procedure, as otherwise, if one looks, most often, one would find these components supplied prove not correct in the instance at hand. If your machinist just shrugs his shoulders and says "I don't know", then your at the wrong shop.

Also be aware, the "cam-effect" or lopey idle is do to the ineffective directional stability of the air motion within the induction tract, caused by the excessive valve timing presented at that engine speed. This means one isn't going to receive both the ruff, "bad boy" idle, and not sacrifice the tip-in throttle response and low speed torque values, some (a case of: "You can't have your cake and eat it too!").

Scott.

[simplyconnected]

I'm glad you have your engine out and at the machine shop. While there, I hope you have removed ALL plugs from the water and oil galleries so that it can be tanked and thoroughly cleaned. Replace your core plugs with brass. Make sure your engine block is clean of all debris before replacing plugs. With the conversion from 'button-type' to thrust plate, you also need a new timing chain set. I suggest a 'true roller-type' timing set as they last much longer before stretching.

CAM: That cam I suggested is an OEM replacement for those who want to retain flat tappets. I replace my cams with hydraulic ROLLER CAMS so that conventional oil works and I don't need ZDDP oil additives (for flat tappets). More expensive? Maybe but also consider the 'subtracted cost' of replacement flat tappets. A word of caution about duration/lift/separation. Don't go wild. Too many beautiful builds were done, then immediately sold because the engine no longer suited the service. A cam that starts producing torque at 2,500-RPM will need a slippery torque converter (which creates more engine heat). Vacuum and rear end gears start making a difference then, as well. We've had members who bought cams, only to trash that cam and order a 'trailer pulling' type cam that produces low-end torque not racing-RPM service.

With a roller cam, you will need shorter pushrods as well. What size? With any cam change, it depends on 'the stack':

• Did you mill the block deck?
• Did you mill the heads 'flat'?
• Are you using the oil baffles under the rocker shaft stands?
• What is the head gasket thickness?
• Are you using stock rocker arms and were the tips dressed?

When Ford assembles engines, they're all the same so 'the stack' variation is well within spec's. A rebuild changes this and many cams come in different lobe heights. The rocker arm angle should stroke through the middle or valve timing and depth will be affected.

After your choices are made and the engine is together, before starting the engine, valve-to-piston clearance must be measured. I install one set of pushrods without valve springs on #1 cylinder (I twist a small wire around the valve stems so they cannot drop down the cylinder). Carefully rotate the crank by hand and 'check' by dropping the valves at their closest point to the piston. Then, measure between the valve stem and rocker arm.

This is particularly important when advancing or retarding the cam but it should be done to all rebuilds. It costs no money to check but it might save a lot of money if clearances aren't right.

New lifters are dry, so this test takes a very light touch. Each lifter company recommends their own lifter preload. For instance, some lifters tolerate a .040" preload. I shoot for .020" but I will allow up to .030" (measured at the pushrod).

Adjustable pushrods (for testing) can be purchased at Summitracing or other speed shops. Once the desired rocker arm ratios and preload is met, order and install the correct size pushrods. - Dave

[Deanj]

I'm not familiar with FE engine cams, but I have some general cam advice. Once I installed an Erson in my 4 speed 1980 L48 350 Corvette. What great results as I opted for a cam I could use with the stock valve springs and was suitable for a 3.07 rear end. That means the low rpm still had enough grunt for those gears.

I recommend a cam that projects a 10-15% HP or Torque increase. It might even be listed as an "RV camshaft" which increase low end very nicely.

Exceeding a 10-15% power increase and you'll not only need new valve springs, but you'll probably need to modify the carburetor and exhaust to keep more low end power. As always, new lifters and pushrods should accompany a new camshaft.

Dean

[mh434]

Scott, Dave, Dean

Thanks guys, lots of useful info there. I will go back over it at the weekend.

thanks

Jon

[StealthSRT10]

So i installed a comp cams 265DEH in mine before.
It sounded so amazing. It was only a step up from the towing cam so nothing crazy. your manifold vacuum will go down some but if you still have the vacuum booster pump then you should be fine i would think.

COMP Cams K33-207-3 Camshaft Kit (FB 265DEH-10)

the whole kit is on sale on amazon for $390.
comes with springs lifters cam and timing set.

It was a bit peppier for sure. threw out the rear end first time i gave it gas going around a corner. defiantly didnt do that before.

[simplyconnected]

So, your choice in cam can only be made by YOU. What will you use the car for, MOST of the time?

As cams get more wild, they produce more high-end torque. BUT, there goes your idle, your vacuum, gas mileage and stop lights become a challenge. Been there.

No one cam is better than another. They are simply ground to meet the service you are looking for. It's up to you to determine exactly what that service is.

Stock cars come with powertrain systems that we're all familiar with. Changing the cam grind can mis-match the components. If you're ready for that, then ok. We can get another 100-hp out of your engine, that's not a problem. But... this isn't going to be a grocery-getter or a parade cruiser any more. - Dave

[scumdog]

For what it's worth the 429 in my '55 F00 is (from memory!) an Isky 270.

It has a Torker intake and 780 Holley.

I get good gas mileage on the highway, it hauls from idle BUT it is as hot a cam as I would want with a stock torque-converter, the vaccum at idle is lowish but enough for the brakes to still work well.

And it gives a lumpy exhaust note at idle and the overlap makes for a 'rich' exhaust - and gas economy cruising around town is not flash!.

[Woobie]

This link supposedly contains the original specifications. Included for the squarebirds is a 270/270 with a lift of 441. Nearly indentical to the later 390 6 barrel camshaft.

http://www.mercurystuff.com/fe-camshaft-specs.html