440Source "Stealth" heads, your experiences and opinions

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jos51700

jos51700

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I'm looking at a set of the "Stealth" heads from 440Source. This would be a mild build in a 100% street application. I'm just curious to see what those of you that have run them, had friends that run them, and know those that hate them, what have you experienced?
I do NOT like the fact that they're made in China, but I'm not seeing any other stock-type aluminum 440 heads on the market.

All opinions are welcome. Thanks! JOS
 
I had if I remember right three sets of 440source heads. The castings a very nice. Out of the box they flowed right around 267cfm. They should be checked out because all heads should be checked out. They respond nicely to a good valve job. With a little port work they will easily flow over 300cfm with the stock valves.
 
Can't beat them for the price. Tons of builds out there with their stuff and most of the time people seem to be happy with their parts.

Several years ago they would get bashed for this or that on the forums but they seem to have weathered the storm. Those heads fill a void for guys that don't want a race engine but also don't want to pay a similar amount or more to have an ancient, used up set of 906 heads re-done.

And really, just about everything is made in China these days, almost can't avoid it anymore. It's also common for vendors get the raw castings done there but machine them here. Pick your poison.

But speaking from direct experience, I built a budget-minded 383 stroker for a friend using 440 Source parts including the heads and their complete stroker rotating assembly. 450hp @ 6,000 rpm and 475 lb./ft of torque. .060" over 383 block with a mild hydraulic cam, RPM intake, 750 carb and headers. Nothing earth shattering but it is plenty capable for the application. Motor is in a heavy '66 Fury but it gets up and goes when he wants it to and he couldn't be happier.
 
Off topic but I ran 8.60’s@155mpn with their cranks, rods and pistons. I ran 8.40@160mph with their rods.
 
I have experience with them and it has been 99% positive. A mild 440 can make 475hp pretty easily on pump gas with 9.5:1, 750cfm carb and headers.

Three thungs I do before running them (specific to these heads):

1) Use a rotary file to improve oil drainback, especially around the spring pockets. This will help avoid seepy valve covers.

2) Install thread inserts in the valve cover bolt holes.

3) Use a *minimum* of a 4.410" bore head gasket to avoid the fire ring overhanging the chamber.
 
Running 440 stealth on my warmed up 400, about 10 years now. Back in the day you threw away the locks and keepers and went with comp. Mine dynoed at 438 hp and 515 torque.
 
69conv said:
Running 440 stealth on my warmed up 400, about 10 years now. Back in the day you threw away the locks and keepers and went with comp. Mine dynoed at 438 hp and 515 torque.
Click to expand...


I think now you can get them updated with 10 degree stuff. It’s a shame but Edelbrock heads still come with 7 degree stuff.
 
7 degree locks are probably OK if you’re using them in a milder application that is mostly part throttle operation. If you’re running a big roller cam with high RPM you’re likely beyond using those heads anyway. Sure there are instances where people push them to the limit but in those situations the heads are certainly not 'as-delivered' in any sense.

On the build I did, we changed the 7º locks out but only because we changed the valve springs to suit the cam. Even then it was debatable and we probably could have gotten away with using them. If you're not changing the as-delivered valve springs they will be fine.

I'd say the one drawback to Stealth heads is that if you want to run any sort of cam, you're going to be changing the valve springs. Once you're at that point you'd just get 10º locks. 440 Source probably figures that most people will do that anyway. The heads have been $1,000 for years, they'd probably sell less of them if they were suddenly $1,100.
 
The heads are currently $1200 per set.

My 511" Stealth headed engine has a big solid roller. It makes excellent power even thought it is over cammed for n20 use. The only thing required for that upgrade was .080 lash caps. I am going to have a set CNC ported with MW port windows. Those heads will get +.100 long valves.
 
Have a set on warmed over 383. So far so good. Checked out good before they went on, no issues. Very good people to deal with. The straight spark plugs helped my header situation. I personally would have no reason not to recommend a set of these heads. Good luck…..Swingn’
 
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