4.6 vs 5.0

[trwp72]

4.6

So the 4.6 does have main and rod bearings.. ( looked up the specs.. ) I was told that the mains and rods were machine down to the excact tolerences, so the the main and the rods acted as their own bearings.. I thought that seemed a little bit stupid.. but I know everytime the PD has had to replace an engine.. they just put a new engine in the car.. instead of rebuilding.. and threw the old engine away.... I guess it costs too much for the machine shop work etc... to justify rebuilding them... who knows! Tom...

[93 Marquis]

I'm feeling lots of "Stock HP" envy here.

Both engines have advantages and disadvantages. Neither in stock form is going to live up to it's maximum potential. Then again when was the last time Ford built a motor to it's full potential.

Someone said the fun is in modifying them, and I agree. I have had both over the years, and if I had to pick my all time favorite engine I'd say F the small blocks! Give me a FE any day....428CJ baby!!!

[Jackup460]

Ok, lets just get off topic here.

Which engine is more reliable and durable?

5.0 parts can wear and still perform.

[zwack88]

I may have a 4.6 but a 5.0 is still better in my opinion. Parts are way cheaper for 302s and performance mods are cheaper too. So in that aspect you can build a way better performing engine with out as much green. But when my 4.6 dies in my car I'm going to swap it over to a 460 with a C6 tranny. :evil:

[93 Marquis]

"reliable and durable"

If you take care of the engine properly then either one will give you 200k miles of happy motoring.

If you plan on neglecting the engine then the 302 will certainly last longer than the 4.6. It can handle abuse much better than the tighter tolerance 4.6 will.

[p71towny]

I've seen plenty of beat ass 5.0's with rods knocking still driving, but I also see alot of high mi 4.6 running just fine. I dunno, but my towny will prolly take alot of the boxes out there just fine :guns: And look good while doin it. IMHO a real v8 needs to be at least 300ci. not 281

[Jackup460]

Agreed

[grandpaslincoln]

BlazingStang-

I don't know if the 67 mustang ever came with the 302. Do you know of one that does?

As far as I know, the 302 was first introduced in 68, but it coulda been put in a few 67's first.

In 1968 Ford produced the Tunnel Port 302 to compete in the FIA Trans Am racing series, but was crushed unmercifully by the competition. That's when Ford designed and built the Boss 302 in 69.

The Boss 302 heads were a variation of the heads Ford was designing for the 351C 4BBL.

[Mercracer]

I don't know if the 67 mustang ever came with the 302. Do you know of one that does?
As far as I know, the 302 was first introduced in 68, but it coulda been put in a few 67's first.

I have never seen a 302 in a 1967 production year Mustang. 1968 was the first year of production and the only year of a 302 4V until 1983. Even the Shelby got a 302 4V in the GT-350 for 1968. What a dissapointment compared to the HiPo 289 from the 2 previous years. The 1969-1970 Shelby GT-350 351W 4V wasn't much to brag about either.

[Mercracer]

IMHO a real v8 needs to be at least 300ci. not 281

The 306HP Shelby 289 held its own.

[Lincolnmania]

ok you guys are lost on your smallblock history
1962 the 221 v8 is introduced
1963 the 289 was introduced
1964 the 289 was introduced
smallblocks had a different bellhousing pattern (5 bolts) untill 1966 when they became 6 bolts
1968 the 302 is introduced
1969 the 351 w is introduced
scott

[Mercracer]

ok you guys are lost on your smallblock history
1962 the 221 v8 is introduced
1963 the 289 was introduced
1964 the 289 was introduced
smallblocks had a different bellhousing pattern (5 bolts) untill 1966 when they became 6 bolts
1968 the 302 is introduced
1969 the 351 w is introduced

Who's lost?

1962 the 221 AND 260 were introduced. I have a 1962 Fairlane 4-door project car with an untouched 221.
In 1965 the 289 adopted the 6 bolt bellhousing pattern. Early production 1965 Mustangs had 5 bolt 260 and 289 blocks.

[Southern_Pride]

Ill take the 5.0 anyday. I run the dog shit outa mine and it still fires up every time. My 86 knocked for over a year and sounded like it explode at any second. Smoked like a pot head and id rev the shit out of in the yard every for about 30 minutes for the first month after i got it. Revving an engine with a knock is a bad idea tho

[SleepyMerc]

The 302 is a stroked (believe it or not) 289. The 221 and 260 have smaller bores. The 289, 302, and, I believe, the 351 all have 4" bores, though the 351 has a taller deck height.

The 4.6 has better counterbalances on the crank so it doesn't need any external balancing. Even the cast cranks have a great history of withstanding abuse. The block also has crossbolts on the mains. They dont have the same problems with main caps walking that the 302s do. So the short block has a lot of potential to withstand abuse. If you really want to rev it though, the SOHCs have hypereutectic cast pistons, like the later 302 h.o.s, and marginal rods. Anything over 6500 rpm is a crap shoot. A 4.6 with good rods and forged pistons is good for 7500 +.

They also have an efficient combustion chamber design.

The downside - the small bore, a little over 3.5", shrouds the valves, so the 2 valve heads are limited. Even with porting and oversize valves and big cams it's hard to exceed 380 hp at the flywheel. For the SOHC you have to buy two cams - $550+. Unless you get 4 valve heads (which can make a lot more power), then you need to buy 4 cams! Intake manifolds are limited in choices and expensive.

The heads CAN be ported. Some companies that do this are VT, Steen Racing, Sean Hyland Motorsports, TEA, Renegade, and a slew of others. As yet there are no aftermarket heads available.

The cool thing about the 302 is that you can easily tailor it to the exact application. It's easy to build a high torque 347 or a screaming 306. You can easily build it to make power in the rpm range you want. And it' is a lot cheaper than the 4.6.

The bottom line is that hot rodding is all about doing what you want. I remember when 302s were economy motors and considered too small for serious power. They were underdogs to big blocks. But FI and hydraulic roller lifters in fox body Stangs changed all that. Now the little 4.6 is the underdog, but there are a lot of guys proving that they have potential too.

The cheapest engine to build for a lot of power is the small block Chevy, but wouldn't it be boring if everybody built small block Chevies? Just because they're cheap? Build what you like!

[Mercracer]

The 302 is a stroked (believe it or not) 289. The 221 and 260 have smaller bores. The 289, 302, and, I believe, the 351 all have 4" bores, though the 351 has a taller deck height.
The 4.6 has better counterbalances on the crank so it doesn't need any external balancing.

The 302 used a new casting block. The bore skirts were extended for the longer stroke. The 302 shares the deck height with a 289, but they didn't just drop a longer stroke crank in a 289 block. The 4" bore is shared by all Ford small blocks (don't care about the 250) from 1965 to the demise of the 5.0 Explorer motor after 2001 including all 351 (352) motors and the 400.
The counterbalances are not "better" on an internally balanced motor. There is enough mass within the counterweights to neutral balance the rotating assembly. Any crank and rotating assy can be neutral (internally) balanced.