tator62

Does anyone here know If the Edelbrock heads are really worthwhile for for the money for a basically stock engine. I’m running a 455 with 10.5 to 1 compression and c heads With a turbo 400 and 373 Posi. Last time I checked they were advertising 100 extra horsepower simply by bolting them on, but is that a fact or just a sales pitch? I figured someone here has had an experience with both and would know the pros and cons.

Owen Miller

GREAT question. I'll be watching to see the response.

THX,
Owen

cutlassefi

Who said 100hp?
There are still a lot of variables to make any blanket statement. Do your heads have small valves or big valves? Stock cam or something different? Stock intake or not? Headers or manifolds?
With that said I believe if you went from a bone stock 10.0:1 ish 455 with small valve heads and otherwise stock components, to a complete top end kit then yes I think 100hp would be pretty close to reality. Otherwise there would be different levels of gains.

oldsmoboogie

Your not going to gain 100 hp from just a head swap. You will need supporting mods and a cam swap. Did they advertise 100 hp with just the heads, or with the “total power package “?

VORTECPRO

I think your looking at roughly 50 HP on a street performance 455 engine build, but thats just a guess.

matt69olds

I have seen many people say the edelbrock heads are a 40-50 hp bolt on. I suppose if you have a 2 bbl 455 and bolted on a pair of heads/intake and carb, then I could see a 100 hp increase.

I guess it’s a question of what’s important? Obviously, aluminum heads won’t look stock. If you can live with the non-stock look, then it’s worth discussing aftermarket The cost of rebuilding iron heads can get pretty pricey. By the time you buy springs, replace guides, valves, and other machine work, it’s not hard to get close to the cost of aftermarket heads. To get an extra 50 hp with a stock engine normally requires a more aggressive cam (won’t idle as smooth) which might need a different converter (more money/labor to install) more compression (more expensive fuel) or a combination of all the above. When you consider all that, 50 hp from a head swap is a pretty good bang for the buck.

83hurstguy

Aside from what's already been posted, I think there are a few other factors to consider since you said "basically stock"... if you're planning to run exhaust manifolds, there's no point in going to aluminum heads. If you are committed to a mechanical fuel pump, you'll want to wait until the new Edelbrock version comes out, as they will be clearanced for one. Otherwise, the older versions require the use of an electric pump or significant mods to the heads to clear a mechanical pump.

cutlassefi

Most mech fuel pumps will clear an aluminum head on a 455.

shiftbyear

Edlebrock package must include a nitrous unit = 100hp

tator62

OK let me clarify this a bit, years ago when the aluminum heads first came out from Edelbrock a Salesman from Edelbrock told me a 100 hundred horsepower gain just by bolting them on. I’ve not talk to a lot of people over the years that Have run them to see how they like them or what they actually got from them. I’m not running exactly stock motor I have a 455 with Forge 10 1/2 to 1 compression flattop pistons, Mondello JM 2022 cam the heads are C with large valves that have been worked over a little bit, edelbrock 04B intake, with the 70 4 speed 253 carburetor and I’m running the W/Z manifolds. Plus I run a turbo 400 with the B&M shift kit and a 12 Bolt posi with 373 gears. I’ve built this car 40 years ago, but it kind a got set back in the garage for a while, raising kids, and a divorce, and now I’m looking at just trying to get it back up in some kind of decent shape. Motor still runs good and strong but I’m sure there’s been a lot of changes over the years and Just looking to get caught up on things. I have been a member on the list for years, just haven’t been active

VORTECPRO

Depending on who worked your C heads you could go backwards bolting on the Edelbrocks........

83hurstguy

Good to know, thanks.

Andy

Exactly, no simple head swap is giving you 100 hp. Not a chance, now headers, cam ,heads, carburetion and good compression its definitely a possibility.

VORTECPRO

Battenrunner built a 455 Olds, it made 474 HP, we took the bigger cam out reccomended by well known cam seller on here and replaced it with a smaller cam, we modified the same heads along with the intake, no other changes, 598 HP, I think thats 124 HP gain. Power peak went from 5200-5300 to 5800 RPM.


https://classicoldsmobile.com/forums...rs-ago-126621/

Andy

cutlassefi

No back to back testing of any single component so what made how much difference. No one knows, especially not Velcro.
Kudos to you Andy for picking up on that.👍.

Battenrunner

The Howards lobe ramp profiles were apparently a fail on the 474hp wheezer combo we had, unless we were willing to install some 1/2 ton truck suspension springs to use as valvesprings to control the valves, and even then, we don't think they would have worked within the parameters of the real world harmonics and physics and our simplistic valvetrain....

The re-do was full of monetary-based compromises imposed by our budget on basically everything, with nothing optimized for the best power output, just the best power output that we could do with what we could afford. Re-grinding the austempered Iron cam core meant that we could only get so large of a cam on the re-grind as well as using the Hyd. Roller lifters we had that could have been better. Re-using the existing old-design heavy and thick-ring Arias pistons that came with the engine, then only being able able to go up to a 2.125 intake valve because of no time or money to custom order valves, being limited by the cheap distributor instead of a crank trigger, and re-using the sub-optimal Moroso oil pan.



If we had done what was recommended by Vortecpro, we likely could have seen 680-700hp and still been a streetable engine using pump gas.

Instead, with his tremendous help, going above and beyond with all of our compromises, we still ended up with likely one of the lowest cost-to-highest performance output Iron-headed stock-stroke 455 (now 469) Oldsmobile engines that runs full pump gas.

Harold Bettes actually did a small calculation for the humidity at that time, and the fully corrected number was 604hp.


Back to back testing..... NO
one at a time parts change-out testing....NO
use of aluminum heads to make big power....NO


Real world streetable power that will run mid 10's at sea level and keep on running without spinning bearings..... YES

I think at this level that the Edelbrock heads would likely be a step back for our setup, but until we see some real world flow testing, we won't know for sure.

I am still hopeful that the new E-Brocks flow much better than the old ones and that they help a lot of Olds guys step up their power to new levels.