First I want to apologize in advance for not being able to locate the Cleveland Forum that has been referenced within some of the posts on this site. Also I know that probably much of what I am asking has probably been covered to death, I just can not find it. I am building a D2AE -CA block (casting date 3A4) for my 1971 Squire. The lifters that came with the block (everything in a box) look like hydraulic lifters. Did Ford put a hydraulic cam in the Cobra Jet block?
Yes, the cam is hydraulic - that was one of the main differences between the 351CJ and the 351HO. Casting date indicates a January 1973 build, if the heads are original they might have the slightly smaller valves from the '72 or '71 production engines.
The rest of the question. The Squire presently has a currently has the original 71 351C, 2 barrel engine that the PO put a Edlebrock RPM intake, Hedman hedders long tube (2 ½ I think), a way to big (for now) 750 cfm Edlebrock carb with a set of Flowmaster 40's on. I plan on using the 2 barrel heads (low end torque) unless I stumble across a set of Aussie heads before assembly and I plan on massaging the heads a little myself (port matching, smoothing out the exhaust, etc.) and I plan on using new Manley valves with springs/retainer-keepers to go with whatever cam kit I get. Since 1971 seats should probably be replaced with new, hardened seats and the guides need redone as well I may as well go with larger valves at the same time. (any suggestions on size?) I have already dropped the block off at the machine shop to get it set up right on the bottom end with a 408 Scat stroker kit bored .40 over. Decked, honed, balanced the whole 9 yards. (The block had already been bored .30 and after magnafluxing and bead blasting it will need to be cleaned up an extra .10.) I have an AOD from a late 80's mustang that I plan on replacing the FMX with (probably a stall speed in the 2000-2500 range) and I'm still looking for a locker with either a 3.50 or a 3.25 for the 9 inch rear end in the pic-aparts around here. Right now it has a 3.00 ratio. I plan on a manageable compression around 9.5 to 10.0, with the pistons being used and shaving the heads an extra .10, after having been being planed true. What I would like is some advice on cams. There are tons of older postings on various cam profiles from other members and I wondered what did or didn't work. I have been keeping up on the recent posts regarding rocker arms and I already knew a little about the geometry and getting the right pushrod lenght, etc.., unfortunately I have my heart set on a roller set up, cam lifers and rockers. Howard makes a reasonably priced retro-roller lifter without a spider (although I do not know anyone who has used them) plus there are a lot of roller rockers out there as well. This will be a primarily street driver (with an extra 4:11 rear end for that 1 time down the strip to see what it can do) so I am looking for torque in the 1800 - 3000 range, especially with the AOD. My prior rebuild experience has been all FE and I know little about the Cleveland. Learned about the low oil pressure at the back mains, although not much else. Any advice/past experience would be appreciated.
I'm running a custom grind in my 3 351 CJs, but to simplify it is very nearly the same grind as the stock 1973 351 CJ cam with more duration. Bear in mind, I run manual trans on all of mine and they tolerate a little more duration, and I build for top end and not drag - I don't care about quick, I build for "fast". I think CJ and 2 seater both have some cam grinds they are very happy with and hope they will wade in here in a short while.
@6delta -- Is it actually safe to plane the heads by .10"?? Or did you mean .010? Be sure to check valve-piston clearance after.
You should pick your compression ratio based on your cam. Your dynamic compression ratio (punp gas) is limited to about 8.5 to one, maybe 8.6 or 8.7 with the right set up. You select the cam, and adjust your compression ratio to match your cam. Your cam should be chosen based on the available intake and exhaust flow, with consideration to how you want the engine to behave. With the right cam, you can run 15-1 compression with street gas, except you will have a very lopey idle at around 1200 RPM. Next, your rear end ratio should be the last thing you decide on. The proper ratio and stall speed need to match the motor you build.
I would be leery of reaming out a bore with a hand drill just a question Glenn what do you gain by bushing the lifter bores? Is this so you use the bushing to increase lifter bore length to help support the roller lifter?
Not Knocking the Ream Glenn I just would rather see it done on a Mill or at least a drill press with the block clamped down. What about the other Question as to the benefits of bushing the bore?
