marky mark

I was wondering what anyone thought about these two crate engine choices.

The 454 has certain ease of installation advantages (no elec fuel pump needed). But gives up about 25 HP & 50Lbs ft of torque to the 502 HO.

The 502 H.O. has the same heads, cam, etc. It's just a bigger version.

It would appear that the 454 Gen VI block is non-siamesed and the 502 block is siamesed. That would mean 3 rebuilds minimum (.030, .040 & .060) with the 454 and only one rebuild with the 502 (.030). Also, the non-siamesed block (502) might tend to run hotter than the 454 but this could be neglible.

This example assumes no other performance parts will be added at initial installation. Cost is cheaper with the 454 (approx $1000).

Given the HP & torque #'s of: 454 = 425hp, 500 trq ( at the flywheel)

& the 502 = 450hp, 550 torque (at the flywheel)

Would the 502 be the preferred choice based on power, or would the difference be less than great.

Thanks for any opinions!!!

Regards, Mark

Bearcat

I'd really go for the 502, Marky Mark. The stroke is the same as the 454, so you're not getting any worse with the rod/stroke ratio. The increased bore is better for horsepower and breathing. You can go up to 496 cubic inches on a 454 with stroking and overboring, but the rod to stroke ratio becomes horrible. That doesn't happen with the 502, and the unshrouding of the valves are better due to the larger bore as well.

The 502 I think has powdered metal rods, which are certainly stronger than the 454's cast iron rods...unless you opt for forged rods. The 502 may have fewer choices in pistons, so your ability to build one for high compression may be limited. For the street however, 50 lb-ft is 50 lb-ft. That's like the torque difference between a 327 and a 383, or between a 396 and a 454. It's a difference you can really feel. I wouldn't fret too much about it "only" being a 25 horse gain. It's not the horses you feel in the seat of your pants, it's the torque. For only a grand more, I'd prefer the torque. That's what will make your launches more violent.

I have a 455 Firebird, which is a well known torque machine. It may have lower horsepower numbers than a comparable Corvette or Camaro with a 350, but it's far quicker. Torque is the force that pushes you deep into your seatback and seemingly warps time and space. Horsepower is torque translated at higher rpm's, but it's the torque you feel.

Go with the torquey 502, that's my vote. :rofl:

marky mark

Thanks Bearcat, well said.

I appreciate the input!

Regards, Mark

need-for-speed

I believe BOTH the 454 HO and the 502 HO have forged rods, crank, and pistons. They make it a tough choice. I'm mulling over the same choices for my '67 Camaro. One thing I've considered is getting the 454 in a short block (not sure if the 454 H.O. is available in a short block but I've seen the 502 H.O. short block advertised so I assume the 454 is available as a short block) and spending the savings on a great set of cylinder heads and a better cam resulting in more than 450 HP. Torque is king but the lighter your car, the less you are able to take advantage of it due to traction issues. With a light car, you may be better off going for the horsepower. I'm not crazy about siamesed cylinders although there may be nothing to be concerned about. Decisions decisions :smash:




[Modified by need-for-speed, 12:43 PM 8/5/2003]

427Hotrod

If you really want to use the GM stuff...it's good,( but I really believe you can buy better from the aftermarket for the same price), I'd go with the 502 shortblock and a better cam and MUCH better heads. The GM/Edelbrocks just aren't the best thing out there for the $$ these days. The 502 block is a strong piece. I know of some race engines based on it that have survived 5 years of running in the 8500-9000 rpm range making 900 hp with stock main caps! And no, it is not a Bowtie..they are just a regular 502 blocks out of dead boats.

The bottom ends of each one of them is essentially identical. But large bore sizes always make good power and if you get 48 more cubes with just a bore increase and the same stroke, it could be a killer deal!

Just build it to 10-11.0 compression (it WILL run on pump gas!) stick in a healthy cam, put on a decent set of aftermarket heads and hang on!! Don't worry about a dual plane intake....you won't need it.


JIM

marky mark

Hotrod, that's a good idea. WA 2 fast did that with his 454HO and likes the results very much.

On the 502 block since it uses the new style cam lifter retention plate device (whatever it's called) I was wondering if at high lifts (say above .650) if there is the possiblilty that the lifters can come out from the retainers?

Thanks again, Mark

OatBoy

i'd say 502

marky mark

Thanks OatBoy.