5.0 cam into a 302 and vice versa........?

Mtrain · 11-20-2009, 01:02 PM

Im going to possibly swap cams with my brother. I built a motor for him a few years ago which was a late model 5.0l engine. I bought the cam for the engine.

He still hasn't finished the engine yet, and said he really doesn't want a cam as radical as the one in the engine.

Im going to visit him next week and I have an old Crane hyd flat tappet cam that I was going to swap into his engine and get his cam and lifters for a motor that I have.

I know that I will have to buy the lifter hold down spider for my old 302 to make the lifters work in that old block, but I know there is something about base circles that I always have to tell the cam people when I build an older engine 302/351w with roller hyd lifters.

Will these swap or not, and if they will what will I need to make it work?

Decurion · 11-20-2009, 01:14 PM

There are 2 ways to put a roller cam in a pre-roller block. The first is to use a reduced base circle cam and stock style lifters, or do like I did and use a standard cam and special lifters. The latter is probably more expensive, but IMO works better because if you ever want to switch cams youre not limited by the reduced base circle. If you try to use a stock cam and lifters the lifters will stick out of the bores too far and could crack the lifter bores and/or the oil hole can come out the end of the bore and you lose oil pressure. I used the Jegs retrofit rollers ($449), but there are others.

66 6 · 11-20-2009, 01:31 PM

Definitely spend the $$ to stay away from the reduced base circle cam. Don't forgot about the different firing order used through the years as you may need to move a few spark plug wires.
Also don't forget about matching the timing chain set and the distributor gear if the new cam is billet.

Mtrain · 11-20-2009, 03:29 PM

Thanks for the advice. How bout the other way around, with my old 302 cam in brother's 5.0l block......

2ndGen · 11-20-2009, 03:42 PM

Quote:

Originally Posted by Mtrain

Thanks for the advice. How bout the other way around, with my old 302 cam in brother's 5.0l block......

This could be a lot more involved...

If his car is a late model fuel injected motor, then the change in firing order will mess up the fuel injection. Simply rewiring the injectors won't fix this properly, since the oxygen sensors will be getting input from the wrong side of the engine for some cylinders.

Beyond this, and not mentioned above is that some late model hydraulic roller cams are steel and will you don't want to mismatch steel and cast iron distributor gears.

Good luck,
-Rory

Mtrain · 11-20-2009, 04:00 PM

Sorry, I forgot to say that his motor {5.0l} is now in a carbureted Sunbeam Tiger. No fuel injection.

It would seem that to go the other way {ie a 302 cam into a 5.0l} would simply mean a different length pushrod, or maybe a custom pushrod, and remove the spider assembly.

v8only · 11-20-2009, 10:00 PM

just have him run a stock HO mustang roller cam. can be had free..or dirt cheap. Try ebay or corral.net to find a stock cam. the stock ho roller cam's are actually quiet decent

gotstang · 11-21-2009, 09:34 AM

Quote:

Originally Posted by v8only

just have him run a stock HO mustang roller cam. can be had free..or dirt cheap. Try ebay or corral.net to find a stock cam. the stock ho roller cam's are actually quiet decent

I agree, would be a lot faster/easier than swapping in a flat cam and should only cost $30 0r so