Well a while back my 408 got hot coming back from the races. I figured I popped a head gasket or cracked the block or head. Long story short, intake gasket leak.

The aftermath was a wiped out bearings, crank and cam.

When I first built the engine I read that it might be a good idea to use a small base circle cam since I am running 5.7 rods in a 400 block. My cam was XE286H it was custom ground and cost me an extra hundred to have it ground. Is it neseccary to run a small base circle cam?

here are the cam specs:
Intake Duration 050 inch Lift 240
Exhaust Duration 050 inch Lift 246
Advertised Intake Duration 284
Advertised Exhaust Duration 296
Intake Valve Lift with Factory Rocker Arm Ratio 0.507
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.510
Lobe Separation (degrees) 110

also though about upping the ante with a 294H

Basic Operating RPM Range 2,800-7,000 RPM
Intake Duration 050 inch Lift 250
Exhaust Duration 050 inch Lift 256
Advertised Intake Duration 294
Advertised Exhaust Duration 306
Intake Valve Lift with Factory Rocker Arm Ratio 0.519
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.523
Lobe Separation (degrees) 110

BTW: I already have a 2800 stall and .600 lift springs

I can`t speak from experience but I can tell you of the experience my buddy has had with the 400`s. If you grind the rod bolt, you should have enough clearance for most cams. Also, you can get "stroker" rods that have more clearance into the design of the rod. I`m sure someone with actual experience with this will chime in but wanted to give my opinion.

A few years back, I built a 400 small block. From previous discussions I realized the need to check clearances. I used a similar cam from Comp Cams. I bought an extra set of rod bearings and test fit each piston / rod assembly, without the rings. This was with the cam and crank in, #1 piston in the bore, and the timing chain installed setting at top dead center. I then removed #1 piston and test fit all piston / rod assemblys one at a time.

I had to grind a little of the sides of the rod bolts on 5 rods. The only mistake I made was having everything balanced prior to the rod bolt clerancing. I went ahead and assembled it an the small amount I took off didn't seem to affect the rotating assembly. The engine revved quickly and with the dart alum heads, ran a 12.57 at the track in street tires.

you will have to check rod bolt clearance for sure .do as ed as already stated and you should be fine .i really dont think there is any reason though to buy extra bearings just be carefull

I would just go ahead and grind all of them before doing a mock assembly prior to balancing and do the pan rails while your at it, 7&8 are usually pretty close. My machinist ground the rod caps at a 45* but I still had to dissemble to round off the edges. I would have them grind a nice radius. Inspection mirrors and feeler gauges is a pain in the arse but I heard a tie wrap might work if you can get the cam in or clay. I did the clay myself and don't forget to rotate the engine at least twice.


Scat makes a stroker clearanced rod.