I had Edelbrock made MP Hemi heads in the shop a few years prior to 2012....... so it would seem the heads like in the pics should have been out of inventory by then.

Zippy, you’re correct on the stock iron head flow. Original, unmodified 559 heads flow in that 300cfm range.

Funny thing....pretty much everything I had access to that was tested either at the CTC airflow lab or at Arrow racing engines matched up (within a handful of CFM) to flow numbers you've posted, fast68plymouth. I remember noticing that and going "well, it's basically like a lightweight stock head then."

The transition from the 110-M to the Edelbrock-manufactured 110-M1 (someone had a sense of humor with the casting number) began slowly in the 2008 to 2009 range under the same management regime I worked under/same one that replaced the megablock with the world block and did alot of other good, but because these parts don't exactly fly off the shelves and not much of anything was really advertised.... not everyone noticed the 110-Ms had been replaced. Took awhile for word to get out.

Edelbrock layed the option of a higher flowing head on the table, but my management decided to stay with something close to oem replacement. I'd have to guess nobody was ready to open that can of worms.

Don't forget..... MP used to get yelled at all the time by non-racers, for things like 509 cams being used in otherwise 100% stock vehicles (which brought on the wide LSA version, better idle but kind of a dog, and a poor seller), Hemi blocks with wedge motor mounts ("now my exhaust won't fit! thanks alot, pal!")......The last thing anyone needed to hear was "where did all my torque go? I put your $3000 heads with giant intake runner volume on my stock 426, and........"

Looks like the first set of Ede made castings I saw were in 2/09.
They were bought as bare castings, and came without the seats done.

After honing the guides and cutting the seats, but with no blending at all, the big number @.750 lift was 316.

I haven’t looked at any of those in a while, but my recollection is that the as cast intake guide boss is much less intrusive in that Ede made head than the ones in this thread.

As ugly as these were to start with, I think they’re going to work out pretty good now.

Nice results!

They look very similar to my iron heads ootb. Similar #'s after porting as well.

F

Zippy - for reference - the part number is P5153875, package date 3/31/14.

There was a pallet of these at Sherwood back around 2016, I think about a 125 of them.

The “P515” Hemi heads are Edelbrocks(at least, all of the P515 heads I’ve had here have been Edelbrocks).

Plain white Edelbrock box with foam clamshell inside, and the MP label on the end.

The heads in this thread are P4876857.

So Dwayne - based on your experiences - no issues with these P5153875 heads ?

P5153875 is the head I referred to earlier as Edelbrock or 110-M1 (casting number).
Please accept my apology for assuming awareness of that.

It’s predecessor P4876857 was 110-M Casting number, the main topic of the thread.

Yes, 110-M1s are definitely fixed. We didn’t hear of any more catastrophic failures when they came online.
However, to be fair....although the new head was a better quality part,it was not really a higher performing part OOTB. Flow wise, it's not far from it's predecessor...It flows just barely more than stock. The quality improvement made the change worthwhile, though (and opened the door to the Edelbrock Victor Jr when MP turned down that product).

I had to scrounge a little bit this was the oldest 110-M1 specimen that
I remember seeing....hopefully the packaging date is visible. The head itself is long gone
To a customer but the box ended up being used to move office stuff, and I still have it.
At the time this head was shipped, mp was actually selling both new and old, if I remember correctly.
I remember the transition to the new part happening later, and slower than I would have liked.
I’m still going to say 2008 was the real changeover timeframe because it took quite awhile to be completed.

I bought a new set of those and used them on two versions of 472" Hemi builds . The first was 11:1 with .600" solid cam, Indy 426-2 / 950 Demon and the second a .525 " FTH cam , and I changed it 9.25:1 factory type dual quad.two 600 Eddy carbs for a show poodle car when I sold it. Neither version made the power I was looking for. Only About 20 hp difference between the two versions. I guess the iron heads would have been better for OTB use.

Mark

Agreed.
The P515 head is just a nicer made product, even if it doesn’t really make much(if any) more power.

Hello,

Did you by chance CC intake runner volume after porting?

I didn’t cc them before or after.

It was really one of those iiwii type of porting jobs.
There was no target flow number I was shooting for....... I just knew the 300-ish they were as they came to me wasn’t what the builder was looking for.

As I said previously, before seeing them, the plan was a valve job and a bowl blend.
I could have still done that, but they’re building a pretty nice stroker.......and I made a judgement call that the motor could probably take advantage of a little more flow.

Gotcha, thanks.

I doubt I took 10cc’s out of the intake ports.