303 Cams

[CustomCherro]

Well I don't care for lumpy idle or track performance. Hell the stock lopo in there now with the AOD can spin the tires all day no problem. I just want some oomph really. The five speed and a bit more horsepower should be quite fun. If the rear-end wasn't so light on the truck I'd go bigger, but I don't want to tub it out nor do I want to have to have a load in the bed just to get traction.

[1987cp]

Ok, I was told earlier in this thread that my block wasn't a roller block and that I'd need retro-fit HR for it.

Misunderstanding or oversight, perhaps? Or ....

Well I don't care for lumpy idle or track performance. Hell the stock lopo in there now with the AOD can spin the tires all day no problem. I just want some oomph really. The five speed and a bit more horsepower should be quite fun. If the rear-end wasn't so light on the truck I'd go bigger, but I don't want to tub it out nor do I want to have to have a load in the bed just to get traction.

Anecdotal evidence says that with the small "lowpo" intake and exhaust plumbing, a teeny-tiny little cam is just the thing for maximum low end. IIRC, you also get peak HP at something like 3700rpm (thus the stock WOT shift points at about 4000rpm).

I will say, if your lowpo is the original engine in a truck, at least some injected 5.0 trucks allegedly came with flat cams, and the source of that information was also in doubt as to whether his hypothetical flat-cam motors got roller blocks. On the other hand, I knew of a guy specifically looking for a used lowpo HR as a direct replacement for a stock 5.0 truck. For my part, it seems crazy to me that they would have kept producing stock non-roller 5.0 blocks past 1985, but that may or may not have any correlation to reality.

As for the HOs, the CFI HO (such as in the compact LTD LX made through 1986 and AOD equipped Mustang GT from maybe 1983 through 1985) is said to have gotten a flat cam, and may or may not have gotten a roller block. Carb HOs for 1985 got the HR cam, as did all the SEFI 5.0 HOs. IIRC, starting in 1989 they went to a split-pattern HO cam for emissions reasons, but I think the '89-'95 HO roller cam is considered interchangeable with the '85-'88 from a performance perspective.

[CustomCherro]

My engine is an '89 lopo 5.0 out of a MGM. The engine and the AOD were both slapped into the truck I have, which is a 1957 Ranchero. Sorry, I didn't mean to confuse you. But the low end makes sense. I had 4.11s in the rear with a mean shift kit before that AOD fried. It would chirp second with any pressure on the pedal and boil the tires off no problem, but put it on the highway and you get up to 80mph and you're revvin pretty high. But, I'm on my 3rd AOD in a 5 year time frame, hence why I want to stick a 5 speed in there. After the first (and best) one fried I took it easy on them, and they just haven't been able to cope with normal daily driving.
Anyhow, so I take it as a Yes, my block is a roller block.

[sly]

+1 yes - roller