440 Source flow numbers

We had a discussion a while back about these heads. At $1000 for the pair, they are a pretty decent alternative. I would say that they deserve a trip to a machinist for a valve job, to increase flow, and to check for whatever else. My set had 2 valve spring seats under one of the springs.

The numbers are as delivered on the top line, the bottom row represents a valve job to open up the seats and center the valves. I don’t remember any numbers on how wide the as delivered seats were or what they are now.

FWIW, here you go...

So what does a machine shop charge to inspect a brand new set of heads? My local shop charges $500 to rebuild a set of factory heads.(new guides, grind valves/seats and surface head) If a shop is going to charge that, your $1000 set of heads turns into a $1500 set.

.....Which is still a good deal for aluminum heads that are truly ready to go

Me thinks the Eddy 75.0 CC chamber RPM head is a better deal at $1500.00 a set from Summit than having to have the 440 source heads tricked out to flow almost as much as the Eddy do out of the box

Good info, thanks.

Most everyone says the Edelbrocks need to be checked over by a machine shop too.

Curious about cost too, intake picked up ~8% flow improvement.
Exhaust looks like no improvement, so is the juice worth the squeeze?

I think you're all missing the point of a 440Source head ... they are made to be a direct replacement for a standard cast iron head. So compare apples to apples. As they come from 440Source is probably as good as any iron head out of the factory. If you're going to have heads checked, machined, ported, polished, blueprinted and flowed then you probably shouldn't be starting with 440Source heads !!

Unless factory appearance is important! If it is, the 440source are the way to go. If you clean them up even better.

Disagree, dollar for dollar the 440 source heads win just because of the weight first and foremost. Then ease of porting. And deck mill. But if you just slap em on, still 9/10 better than a factory iron head

My machinist only charged me $75 per head for the valve job, remember that he is doing an entire build for me. I picked these heads because I'm trying to keep a factory car looking factory but I wanted to pick up some power. And don't forget that the factory heads that were on the car didn't have hardened seats either.

If I have another similar car to redo, then I'll use these heads once again. For a performance build, it'll be something else.

This was just an informational post.

Have you owned and use them? I have with no problems on the 84 CC version of the RPM heads, same on a set of eddy Victor M.W. heads

I've had both Eddys & Stealths on a couple of RBs.
No big problems with either, though both required a little work on valve job & guides.
I also changed springs on both to a double style.
I like the Stealths for their stock-ish look; the old street-racer sneaky thing dies hard .
Wasn't going for max power on either, but was happy with the results.

Flow numbers are about meaningless on the exhaust side.

I bought a set of 440 stealth heads around 2009/2010. Changed the valve locks from 7 deg to 10 deg since I was running a .533 cam. Ran them for 5-6 years before finally freshening the motor. Had 2 broken inner springs, so put new valve springs on them and had a local guy hand port them. After freshening the bottom end (new rings + bearings), the port job, shaved the heads just a smidgen to clean up the surface I picked up whooping .05 in the 1/4. To me they are the best bang for buck for a head at $1000 a pair. If you want a more serious head, spend the coin on some Trick Flows. I spent $1000 for the 440 source + $500 just for the port job. So I have $1500 into the heads now. I bought a set of Trick Flow 240 and bolted them on a different shortblock, but very similar specs and picked up a good 3 tenths in the 1/4. I also went from 2" headers to 1 3/4" with the trick flows which I think was a mistake. I'm putting the 2" back on for 2021 to see if it picks up even more.

I also forgot to mention that I had the small valve 516 heads on this motor so my flow probably picked up more than a newer head.

I'd do it again.

Do you think that because few seem to test them flowing in the right direction?

They ALL need to be checked and corrected no matter who builds them. Trust me, Edelbrock heads aren't ready to go out of the box either.

Kevin

The back-to-back flow tests I saw back in the day when the source heads came out showed the Eddy RPM heads OOTB had about 10cfm more on the intake at .600 lift. In OP's case dollar for dollar it's looks like he's ahead with 1500 into his source heads vs 1500 for OOTB eddys, minus the chamber volume differences of course.