early block will accept roller cams. I have one. Just have to have your cam built with a small base circle...tell the cam guy you're talking with what you're doing and he'll set you up. That way you can run the factory spider, dogbones, and just drill & tap the 2 little 1/4" holes in the valley. Speaking of which...the 2 holes you'll be drilling/tapping....they're right in line with the #2 and #4 cam bearings so it's best to drill & tap BEFORE you put the cam bearings in the block. No chance of damaging the bearing that way. Also, use the right length bolts. Factory roller blocks use longer bolts to hold the spider down. Use those bolts in a early block and the ends of them will sneak their way down to the cam bearing and partially crush it. Ask me how I know. Hyd Roller advantages: Easier starting, better economy (in most cases) revs quicker, and it won't wear out. Disadvantages: RPM is limited to about 6500 give or take because they aren't designed to be used with lots of spring pressure...and the little light weight springs that have to be used generally let the valvetrain go into "bounce". Expensive. Even new factory lifters are around $20 each. If you go with the factory lifter/small base circle cam, the cam is expensive....generally around $250, BUT it's billet steel instead of iron, which means you'll also have to change the dist. gear if yours has a factory iron gear on it already. You'll also need springs most likely. Sure you can use your flat-tappet springs like I did, but the valves tend to float pretty early....around 6200 on mine. Saw a dyno test once where a guy picked up over 90 HP by installing a rev kit..all above 6500 RPM, on a 331 Ford. I personally prefer a roller cam over a flat-tappet, but it's hard to beat a good ol' flat-tappet solid cam for the money. Next project for me is to put a ranger cam in my Mustang....along with the factory roller followers. Wonder if it'll make any difference?
You can switch balancer/flywheel(flexplate) to any crank... 28 oz and 50 oz imbalance cranks are different. You have to match the damper, flywheel and crankshaft. Then you run into the issue of 50 oz imbalance cranks use a one-piece rear main seal, so to use it in an early block you have to have the block machined accordingly.
Comp Cams will grind any of their hydraulic roller prifiles on a small base circle at no extra charge. If you know alot of 5.0 guys, I'll bet one of them has a set or roller lifters laying around. I got my lifters and retaining assembly for free.
Often, due to it's smaller size, a small base circle cam can't be ground with as aggressive ramps as a full sized roller cam. You can end up with not much more lift/duration "area under the curve" than a good flat tappet cam. You will still have the advantage of less friction with the roller lifters, but at a cost of about 2 or 3 time what a flat tappet setup runs. If you want to run a roller with a non-roller block I would recommend getting the Crane vertical link bar lifters and a full sized cam so that you can enjoy all of the advantages.
Barry, I agree with you from a technical point of view. Which is why I did what I did on my brothers 331ci(crane link bars full size cam) but I do remember racing Mavaholic at the round up only to see his fancy chebby tail lights(not by much I didn't hook I ran him) both times I ran him So in essence the performance loss must be marginal. Then again I could just be making excuses for getting beat.
i think i'm just gonna go find myself a different block and ehh i'm not gonna run hydrolic lifters in my engine :16suspect
I was assuming that he had a factory 302 from a Mav/Comet. I thought the '82 and up 302's/5.0 HO all had the newer balancing method. I know the roller cam showed up in '85 and I believe '82 was also the year that 302/5.0 HO engines went to the 351W's firing order. I shyed away from the roller conversions due to their cost, but every 'expert' that I have spoken to SINCE my build up told me that I should have done it. My Dyno2000 program shows a radical difference in HP/TQ with a roller cam of the same profile inputs compared to hyd. flat tappets. Seth
Here is a link to my cam nightmare if your interested. http://mmb.maverick.to/showthread.php?t=1164&highlight=cam
Zooomzoomguy: Use your old block with a solid roller cam and lifters with linkbars. Comp cams sells them. Nothing special needed, but it is about $300 for the cam and $300 for the lifters. I have the same setup and it works well. Roller cams can have a steeper ramp, therefore, the valves can be more efficiently opened=more power. As for the block, if one is going to run a mild hydraulic roller engine, get a 86 or newer block unless you want to use the whole shortblock, in that case get an 87 or newer HO engine with forged pistons and valve reliefs. For any other mild build, the older blocks are fine and considered to be better by many because the block is thicker in areas. For any serious build, use an aftermarket block. I just realized this is too big of a topic to discuss...we need to trim it down to one question...er, what was the original question
