stealth heads on a 383?

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stroker mike

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Has anyone here run stealth heads on a 383? 440 source also has 915's but that's a real good price for some aluminum heads.. I know I'm out of the loop on these, just wondering if anyone here is running them and how they worked out? I'm trying to shave as much weight as possible. The build so far is a 69 383 hp block .030 over with speed pro flattop hyper's and a comp xe275hl...I don't plan to race the car, (well, not much) just want to have a really fun street machine. Aluminum heads would make it alot nicer to stop with the manual discs... my goal is a nice 425 horsepower and similar torque, with a range from 2-6. I think if the flow numbers on the stealth heads are accurate that with this cam I should be in the neighborhood. Any thoughts? In a 67 dart with a 727 and 3.55's.. TCI 2500 stall... should be good, right? Any help from the head doctor's out there? Thanks!
 
The port volume seems to be a bit large for a 383, and without more converter and gear they may be a bit lazy down low. If you can tolerate this then no issues. But IMO I would use a smaller intake port and keep the velocity up as much as possiable and the engine will be more fun to drive.
 
The problem is with the stock stroke and huge head chambers it's hard to get a decent compression ration with a flat top in a 383. If the shop just made the deck surface flat and installed the pistons, you need to see how far down in the bore they are. Most 383s have taller decks than blueprint and you'll want a static at least 10:1 with it. The best scenario is cutting the deck to get them .015 proud of the deck, then reduce the chambers as far as you can. I believe you can get them down to 68 ccs without any issue (.100") and that will get you a true 10.6:1 with a quench of .034". If you simply bolt on the parts and run the piostons on a factory-but-flat deck you will have a static ratio of 8.4 or so. Not nearly enough for that head as BJR suggests.
 
He really needs more CI to fully use the potential of the large 210 + cc intake runner. Just doesn't seem right to take a new head and cut .100 off the deck to make it work.
 
Yeah, but it's desgined into most aftermarket heads and it's done all the time to get the right result. It's another opinion thing...lol
 
Thanks, guys.. that's what I needed to know. So, then I guess I'll be going with the 915's. I'll have to find other ways to reduce the weight I guess. I just figured with a flattop at zero deck I'd end up with 9.7 or so which would be fine for a street 383 with the cam I chose. Nice quench, too. But if port velocity would suffer that much then there's really no point.
 
If you have not already done it move the battery into
the trunk. That would equal the weight of the alumn.
head versus the cast iron head at least depending on
the weight of your battery.
a.j>
 
Yeah the battery will be in back. So, I think the stealth heads maybe are a good deal if I just use a different piston.... 9.9-10.2 cr and a performer rpm... install the cam at 7 degrees advanced instead of 5, and then curve the ignition... what do you think?
 
Sounds like your adjusting everything to fit rather than getting the parts that fit and in the long run, work better together without tweaking it to suite. I like the iron head plan and the KB piston option with a slightly thicker gasket for pump freindly gas ratio.
Pushing the issue with a iron headed pump freindly ratio leeds to problems later. As carbon builds up and change of season feul blends come into play, detionation can be an issue.
The difference in 1pt. of ratio is small peanuts in the overall output.
 
So I just left a message for Angie at Mopar Engines West, she was the one who pointed me in the direction of the 915's, so I'll see what she thinks and take it from there.
 
rumblefish360 said:
Sounds like your adjusting everything to fit rather than getting the parts that fit and in the long run, work better together without tweaking it to suite. I like the iron head plan and the KB piston option with a slightly thicker gasket for pump freindly gas ratio.
Pushing the issue with a iron headed pump freindly ratio leeds to problems later. As carbon builds up and change of season feul blends come into play, detionation can be an issue.
The difference in 1pt. of ratio is small peanuts in the overall output.
Click to expand...

Sure but heads are a BIG part of a performance engine, and if he's starting from scratch the stealth's are the way better deal.
The port volume is not that big of a deal 'in this case' as would it be if there wasn't enough.JMO:read2:

At least it's not in the same boat as the ol 302 boss.

I don't believe he needs 7* of advance but 4-5* would be ok.

I think for mike that if he buy's the same brand alloy pistons at a higher 10.1-11.1 compression and go's with the stealth heads he would be glad he did and it wouldn't take any honing just a lil disassembly-reassembly.

I see 906/915 flowing 212-218cfm stock meanwhile the stealth's are flowing around 275-290cfm out of the box and have the iron beat through out the low lift flow range so it's hard for me to tell a guy not to just change pistons and go w/stealth heads.
If it was me I'd buy the stealth heads and make them work cause I wanna go fast and not fart around.JMO:cheers:

right on mike, good luck!
 
I see 906/915 flowing 212-218cfm stock meanwhile the stealth's are flowing around 275-290cfm out of the box and have the iron beat through out the low lift flow range so it's hard for me to tell a guy not to just change pistons and go w/stealth heads.
If it was me I'd buy the stealth heads and make them work cause I wanna go fast and not fart around.JMO:cheers:

right on mike, good luck![/QUOTE]

Hmm,I was not aware of this. In that case I need to rethink my approach. I was considering ported iron heads,but the weight savings with aluminum and detonation issues with iron are something I never even considered.

The stealth heads were my first choice for my 451 build
 
needsaresto said:
I see 906/915 flowing 212-218cfm stock meanwhile the stealth's are flowing around 275-290cfm out of the box and have the iron beat through out the low lift flow range so it's hard for me to tell a guy not to just change pistons and go w/stealth heads.
If it was me I'd buy the stealth heads and make them work cause I wanna go fast and not fart around.JMO:cheers:

right on mike, good luck!
Click to expand...

Hmm,I was not aware of this. In that case I need to rethink my approach. I was considering ported iron heads,but the weight savings with aluminum and detonation issues with iron are something I never even considered.

The stealth heads were my first choice for my 451 build[/QUOTE]
.............................................................................................

that was stock flow.
In the over all scheme of things full ported BB iron go's 270-290cfm but so do sb j heads so....what the heck?

They can be made good but with heads as cheap as stealth's it makes stepping up more affordable.
 
Thanks. Still learning on the bb stuff. Any good online reading for that subject?
 
It's not all in big ports or flow #'s or material that there made of. But more so what the engine needs and wants. Like what lift cam are you planning on, how much compression ratio, what intake manifold, and carb?
You have to look at low and mid lift #'s not just peak, because this is where your camshaft is going to be running most of the time. It's far more important to have very good low and mid lift #'s below the cams peak lift than something higher than the cam actually opens the valve.

The 440 source heads show 290 cfm @ .600 peak on the int. and 220 @ .600 on the exh. and this is with a 212 cc int. runner. A set that I did with a 452 head and 2.14 valves which are the smae size as the stealth heads flowed 293 @ .500, more air at .100 less lift. And the port volume was only 186 cc's. I also did a set with port size compareable to the stealth heads @ 213 cc's and they flowed 300 # .500 lift, and this was still a factory casting, 906. Now the factory HP MP Max Wedge heads are 210 from the factory and with a minor cleanup of the ports, just at the gasket and taking the flashing out in the bowl and they flow 314 @ .500 and 343 @ .600, the exh. went 240 @ .500 and 253 @ .600. So in my book it's hard to compare the old cast as stock to a aftermarket head with revised ports. But when you compare the new aftermarket heads with new factory heads both in the same conditions they don't fare so well.

But in any case, it's not how much they flow at peak but whats under the curve that counts. What needs to be found out is what the stealth heads flow @ .200 and .300 and .400 lifts. This is what a 452 head did with a gasket match and bowl blending.

lift.........Int
.200......178
.300......226
.400......259
.500......293
 
So, I'm gonna be running an rpm intake, 800 cfm demon, and the cam has lift at .525 both sides. Cam quest software states that with stock hp heads with 2.08-1.78 valves it would make 447 hp and 467 ft.lb.s, 9.5:1 cr. Now, that's right in my target range for output, but I really wanted this build to be above and beyond the stuff I've done before, the price of the aluminum heads has me thinking long and hard about them. If the heads have a VE that matches the lift of the cam, and save me the time and cost of porting and flow bench an cc'ing, then I think they are just right for me, cause shaving 50, 75, 100 lb.s off the front of my dart would make a dramatic difference to me. But the main reason I chose this cam was because of the good bottom end, and if I'm going to stall airflow at low lift with the giant 2.14 intake valves then I'd be defeating my own purpose. I have been there before, put 340 j heads on a 318, the top end was awesome, but it needed 2500 stall to launch with any real force, and that was with a little 268 cam. Ouch. The same heads on my 371 were freakin awesome, cleaned up the valve guides and matched 'em, so... What will these heads do at low rpm with this cam? Will it be a dog around town? I don't want another 2 second 60 foot time. Know what I mean? I want some street aluminum heads is what I'm saying, I guess. But they don't really exist, huh?
 
I just saw the numbers for the new procomp 440 heads....jeeez! 2.20 intake valve! those are big heads! I don't think I need those....Ha!
Ok so I just spoke with Angie at MEW and she said that I should forget the 915's, that eddie or stealth heads either one would be a great choice. She said to keep the cr at 9.5 and I'll be really happy. I trust her, i know the work that comes out of that shop to be some of the very very best, so I think I have my answer! Thanks, guys.
 
BJR Racing said:
It's not all in big ports or flow #'s or material that there made of. But more so what the engine needs and wants. Like what lift cam are you planning on, how much compression ratio, what intake manifold, and carb?
You have to look at low and mid lift #'s not just peak, because this is where your camshaft is going to be running most of the time. It's far more important to have very good low and mid lift #'s below the cams peak lift than something higher than the cam actually opens the valve.

The 440 source heads show 290 cfm @ .600 peak on the int. and 220 @ .600 on the exh. and this is with a 212 cc int. runner. A set that I did with a 452 head and 2.14 valves which are the smae size as the stealth heads flowed 293 @ .500, more air at .100 less lift. And the port volume was only 186 cc's. I also did a set with port size compareable to the stealth heads @ 213 cc's and they flowed 300 # .500 lift, and this was still a factory casting, 906. Now the factory HP MP Max Wedge heads are 210 from the factory and with a minor cleanup of the ports, just at the gasket and taking the flashing out in the bowl and they flow 314 @ .500 and 343 @ .600, the exh. went 240 @ .500 and 253 @ .600. So in my book it's hard to compare the old cast as stock to a aftermarket head with revised ports. But when you compare the new aftermarket heads with new factory heads both in the same conditions they don't fare so well.

But in any case, it's not how much they flow at peak but whats under the curve that counts. What needs to be found out is what the stealth heads flow @ .200 and .300 and .400 lifts. This is what a 452 head did with a gasket match and bowl blending.

lift.........Int
.200......178
.300......226
.400......259
.500......293
Click to expand...


Bowl blending & gasket match? hmmmm.....

How much with customer supplied castings would those heads cost with valves, guides, seats, milled, VJ, ported like above etc?

And have you had any of these stealth heads in your hands to work on?
 
The last time I bought the valves like in those heads they were $20-$22 each. But as we know the price more than likely changed since then, and that was just last fall. Guides are $148.00 and seats are $200.00 as I use Serdi seats. Milling is $55 for the first .030 per head then it depends on how much more you would want off. As the intake side would also have to be milled for the intake to fit. At a rate of $1.00 per .001, .040 = $40.00 an so on per head. The VJ is $250.00 and the porting of the bowls and gasket matching is $400.00.

So you would be looking at about $1,108.00 plus parts and shipping.

As for the stealth heads I haven't as of yet.
 
Angie is a great head porter. I'm impartial to MEW but I can tell you she knows her stuff.
 
$1,108 + $140-180 valves $60 retainers $16 keepers $90 springs

So for around $1454 we can have iron heads from you that flow the following?
ift.........Int
.200......178
.300......226 look at the .300 lift flow thats huge for a street head!
.400......259
.500......293 killer!
If so I would take these over eddlecrocks for sure and unless pushing comp to the limits on pump gas would rather have iron anyways.

You gotta admit though, for $900 assembled those stealth heads are pretty bad assington.lol
 
hey i just did a 383 with 440 source heads i got 10.1 to 1 compression btw. using a 39thousands inch gasket and keith black 30 over valve release flat top pistons call keith black lol worked for me
 
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