Yes, know quite a bit, ... have castings here,

it's basically an SR-20, .. my same cnc programs go in that casting
as the SR-20.

Doing an aggressive cnc port, large valve, etc.

It moves air, I'm expecting an honest 520 from a reasonable size
port / throat. Could get more if you really blew the sizes out.

Curtis

 

So any benefits to using the dart over the SR-20? What is the rocker setup like on the Dart?

 

Yep, it's a bad dude. Got a pair sitting right here.

As cast, 50 degree seats... conservative valve jobs it rolls 466 cfm at 1.0".

Takes same rockers as Brodix SR20.

 

Chris.

466 with what size valves? Can you post figures for the entire lift range?

 

2.400 Valve. I haven't flowed it on my bench.

 

The dart head is a nice piece.

 

We got an as cast set on the floor waiting to be tested...Would like to see my porter grind on em' and see what he can do.

 

 

It looks very similar to the sr20. The cast port looks very big also. From what you guys see is it a improvement from the sr20 and is there more potential with these.

 

Why don't they put an exhaust rocker boss like that on the 24 deg pro 1?

 

There's 2 mounting holes in line, per exhaust valve. It's pretty robust in my opinion. Again, from the looks of it, Maskin took the SR20 rocker gear, and made it fit his head. It's going to be the same part number as we already mocked up an SR20 set from T&D.

 

Chris or Curtis
Could you post a pic of the as cast combustion chamber and bowls.

 

They come CNC finished, no as cast unless you specified it.

 

I seen the flow sheets and dyno numbers on a 582 ... These things are BEAST MODE

 

They are a little aggressive in the short side right from the get go... which, isn't a bad thing IMHO, considering that these heads are probably aimed towards more of a high end engine.

 

Yes they are nice, ... but the rather large cast port is the issue
I had given as feedback to Dart, .. nice but really limits the use
of the casting.

I like it, ... nice casting as all Dart castings are.
Not inexpensive

Curtis

 

Are the chambers around the same size 93 to 96cc. It think it's great that they are using the same rocker assembly. IMO my valvetrain is rock solid on my sr20s.

 

What is a General Price on these????

Aren't They spendy enough to just go right to a pb1200 or The raptor heads.........

And I understand it if it's a rules thing, but just asking as a customer of mine ask about the sr20's and
I thought for the money, I'd go right to the raptor heads......No rules just a bracket deal that want big power.

 

They aren't cheap once you involve porting and finish work...

 

That's what I thought.....

Got a ball park............... What are you using them on???

I want 1200hp+++ out of a 582..... that can run a whole season

would like more in the line of 1300HP.... but it's going to need to be a pretty damn good effort and not sure I can do it.........

 

I'm using them on a twin turbo drag week engine.

 

I have 2 sets of them. I sent one of the heads to T&D to verify the rocker arm situation and the Brodix SR-20 rockers are the same to go on the Dart heads. The intake bolt holes on the Dart heads are in the correct location to line up with std. bbc manifold bolt holes. The head bolt holes are spot-faced for regular large washers for the head studs. They are nice.

 

How does the price compare to the Brodix for the raw castings?

 

slightly less, .. but close.

 

THANKS. Can you tell us what the min area is for the Dart as cast? Looks pretty big as cast in the photo.

Maybe they will make a porter's casting as well.

 

I asked several people at Dart including Richard
about a Cnc core head and the answer
was a solid "NO".

Not much flexability for porting but we will see.
I have a very good big inch program for
the SR -20 that I think will fit, and with some
updating to the new casting could be killer.

I'm gonna be honest,, at the cost if the SR 20
and these new "conventional" heads,
I don't know why people don't look closer
at the 18* spread port stuff like the Brodix 1803.

 

Curtis

Were you surprised about the "NO" to the CNC core? When you say CNC core, do you mean Edelbrock pro port style casting, with the thumb sized intake ports, or just something a bit smaller that will allow porters some more flexibility with there designs.

How does the as cast Dart compare to the as cast Brodix for size and flexibility?

 

I'll run a probe into them over the weekend
and tell you exactly what the CSA is

 

Curtis,

Did you manage to get any CSA measurements?

 

Edelbrock has a few new castings,, DR17 and
a new 24*, but they are painfully slow
at producing them and getting them to market.

Curtis

 

So what are these called? SR20s? Or Pro-1 20* heads?

 

Dart says you can use a conventional 24* intake and you can use the same headers in most cases, with that being said that makes it a little cheaper to change over using their stuff vs the sr20.

 

Doesn't the sr20 take the same intakes and headers as conventional 24 deg as well, just needing spacers for the front and back rails?

 

Sounds like dart is making a peanut port 20....