Comparing bone stock 88 cc 452 big block heads to bone stock, out of the box edelbrock 88 ccrpm heads, does anyone know the flow numbers stock vs. stock? Wondering if there would be much gain going from bone stock 452 heads to bolting on a set of bone stock RPM heads..again, both 88 cc..

there was a thread way back on this & the concensus was that just iron to alum was nothing earthshattering in itself. the eddys would have better ports & I would think a better combustion chamber tho that might be minimal & the alum would support a higher octane. You might Google Steve Dulcichs' porting articles cuz iirc he had info/caveats on them.

Depends on the rest of the combo.

The rest of the combo would stay the same. im saying head swap only, what the increase would be, if any.. Its in a 1972 dart swinger. 9.4:1 440(TRW-2355 pistons), 284/484 MP cam installed 4 degrees advanced, Holley street dominator intake with 1050 cfm 4 bbl., 1 7/7 fenderwell headers, electronic ignition at 20 initial, 34 total. The psitons have a compression height of 2 061. and currently bone stock 88cc 452 heads..How much increase would i be looking at by swapping the bone stock 452 heads for bone stock 88cc edelbrock RPM heads?

What?

There are anecdotal sayings that aluminum will support higher compression, but the only data I have seen doesn't necessarily support that.

Years ago one of the hot rod magazines did a dyno test to compare iron vs aluminum heads. They got one of each from the same manufacturer that were as identical as possible.

They tested for heat related differences primarily, they found nothing outside the margin or error with either head and multiple coolant temps.

When it came to compression tolerance the engine tested was almost 11:1 and showed no signs of detonation with either head setup and they were running 91 octane.

Now this was a dyno test only, who knows how it would act on the street.

Dyno test article

I'm not a head porter, and I do not have a flow bench, but have seen a lot of info from professionals. Your looking at probably 220 - 225 cfm on a well prepped stock head with a good valve grind, and probably 265 - 270 on the Eddy's at your max. lift

Not sure why you would choose an open chamber aftermarket head when for the same or less money you could get a closed chamber head, and get both a bump in compression ratio while also getting good quench distance.

Putting the 88cc RPM on that combo would be a mistake.

Use the 84cc head...... should be worth 40-50hp over a stock 452 on that combo.

Save yourself a little $$$, and just buy the E streets.

That is a very mild combo that you have so I agree with Dwayne, buy the closed chamber E streets and you'll pick up some power. Could be 40 to 50 as he says, could be a little more if you gasket match the heads and the intake.

I was asking because these RPM's i speak of are a used set at a really good price and ready to bolt on and go..Thats the only reason i was looking at these open chambered heads. I guess i will wait and get closed chambers when i can afford it. Whenever i DO get to buy a set, the only thing i will have done to them for a while will be to have them checked by a machine shop before installing them...no port work or anything for a while, so THATS why i want the best bang for the buck when it comes to choosing an aluminum head.. It would be different if i could buy new heads AND have them ported and all right at the start, but it would be a good while after buying them that i would be able to port them, so again, whichever head i buy, i want it to be the best one to bolt on as they come, besides being checked out. So, with my combo, what head would be the 'ONE'? I want something that doesnt need different rocker arms or this and that..

I would go with the ones Dwayne suggested (he's the man on this stuff). You'll certainly feel 40-50 HP. The ones in front of you might be a killer deal but if there is no gain or even a loss then you wont be happy (or save the killer deal ones for a future build with the right pistons).

Why do you think the open chamber is such a good deal? Save your money and by the right heads.

I will save for the better heads. Thanks!

The top end of any motor is the stopper or the best way to make more power with little heads, carb, intake and exhaust along with the cam is to make all of them bigger to flow more air and fuel
You can make 500 HP with the correct good stock type heads and after market intake, carb, cam and exhaust on pump gas pretty easy
With better heads and the same other parts you can add from 20 to 100 HP more

I just figured those RPM heads would flow better out of the box than the stocks..

We used a pair of used bone stock 88cc Eddy heads on a 440. True 10.0-1, 557 Mopar solid, headers, old Weind 2×4 w /2 Eddy 600, 410 gear, good converter. All stock street 65 Belvedere minus exhaust with 9×28 slick, 11.30s@115

something I've noticed in the stock vs edelbrock head thing is that the edelbrock does seem to burn a little better. in my case a little easier to set the carbs up for a clean burn. I don't know exactly why; maybe the chamber , maybe angle plug, or maybe the way the air exits the intake port? as far as power goes my comparison is between a set of stage V's fast68plymouth did vs 84cc edelbrocks, with just me cleaning the boogers up in the intake ports in the edelbrocks, good quench both times, not a big difference in power between the two heads. the iron heads were easier to set up the rocker gear vs edelbrock using off the shelf parts. the edelbrock had much better retainer to seal clearance for higher lifts. the 88cc edelbrock is for quench dome pistons. they will run with a flat top piston but would work better with quench domes. the edelbrock should give a very noticeable power increase over a stock '452.

I just wanted to highlight that Lews ported stage v’s are a huge step up from a set of untouched 452’s...... so it’s expected that there would be very little difference in power between them and a set of RPM’s.

Ok, so if the stave V's are a big step up from untouched 452's AND the stage V's are similar in power to the RPM's, then why wouldn't those RPM's help me muchbeing they ARE a big step up from 452's? Just asking to learn..

the rpm's will help your performance. just use the 84cc head. my guess would be in the 40hp range increase, BUT pay careful attention to rocker and push rod geometry with the rpms.

I think im going to wait and get the E-streets instead because of the valve train mess. These RPM's were used and at a good price and ready to bolt on, so I was curious, but sounds like not the right head for what I want. I do want to save for a set but would like recommendations on which set..I know a few on here said the edelbrock E-streets, but is that the final recommendation because there are the stealths, trick flows, edelbrocks, etc..Like I said, I want the best bang for the buck as far as straight out of the box with no porting..just checking them out and corrected at the machine shop if needed..