World Products vs. Dart Heads

General engine tech -- Drag Racing to Circle Track

Moderator: Team

Post Reply
bobdar
New Member
New Member
Posts: 10
Joined: Sat Apr 02, 2005 5:12 pm
Location: Lakewood, CO

World Products vs. Dart Heads

Post by bobdar » Sat Apr 02, 2005 5:21 pm

I'm involved with an eligibility question that I need some advice on. There are two aftermarket SBC cylinder heads under consideration, the World Products S/R and the Dart Iron Eagle. Both would be cast iron, straight plug heads, with porting and combustion chamber modifications allowed. Are there real performance differences between the two? If so, why? Any comparisons on the internet? Thanks in advance.

bill jones
Guru
Guru
Posts: 2516
Joined: Sun Sep 05, 2004 6:38 pm
Location: salt lake city, ut
Contact:

Post by bill jones » Sat Apr 02, 2005 5:51 pm

-The SR heads are street replacement heads and they are not too bad compared to the older SBC stock heads.
-BUT--the Iron Eagles are 100% performance and race bred pieces with the main intentions of being used on wide open throttle race engines.
-The SBC SR heads that I have seen flow about 191 CFM at .500" lift as they come stock, and then about 222 with a mild porting job.
-The Iron Eagles I've seen flow about 266 out of the box and 287 with a mild port job.
-The Iron Eagles come with intake port sizes from 180CC to as large as 230CC's where the SR heads are small probably 166 to 175 range.
-------------------------------------
-The exhaust flow on stock SR's is about 126CFM at .500" lift, then about 181 with a mild port job, and the exhaust on the Iron Eagles is about 169 stock and 195 with a mild port job.

Fkned
Member
Member
Posts: 83
Joined: Mon Jan 03, 2005 12:15 pm

Post by Fkned » Sat Apr 02, 2005 7:13 pm

The Iron Eagles have bronze guides also,big selling point for me.

bobdar
New Member
New Member
Posts: 10
Joined: Sat Apr 02, 2005 5:12 pm
Location: Lakewood, CO

Post by bobdar » Sun Apr 03, 2005 3:39 am

Thanks for the replies. What differences are there in the combustion chambers? The Dart is purported to have more a "heart shaped" chamber, whereas the SR heads are said to more closely resemble the OEM style. Is that correct?? Is there a performance advantage in the Dart combustion chamber design??

bill jones
Guru
Guru
Posts: 2516
Joined: Sun Sep 05, 2004 6:38 pm
Location: salt lake city, ut
Contact:

Post by bill jones » Sun Apr 03, 2005 12:18 pm

-I haven't worked on the Eagles for a while but I think they are available in 68 and 72 cc where the SR's are more likely 72 to 76.
-The Eagles have the chambers shaped to help the air and still squeeze the chambers smaller.

PDQ

Post by PDQ » Sun Apr 03, 2005 8:32 pm

The SR heads are like Bill said more like older GM heads, they make a good replacement head. The World Products Motown 220 head would make a better comparison to the Dart Iron Eagle. Take a look at the new Dart Plantinum Series iron head. They say they flow 10% better than the Iron Eagles and they are only about fifty bucks more ! Alot cheaper than sending the Iron Eagles to the shop to get the same results.

nova john
New Member
New Member
Posts: 23
Joined: Sun Apr 10, 2005 10:18 pm
Location: New Jersey
Contact:

Post by nova john » Sun Apr 10, 2005 10:29 pm

Honestly, it is quite a difference between the two heads. I was going to build an engine using some S/R heads I had laying around for a *very* low buck DIRT racing engine. What stopped me was the water passages around the spark plug side of the head. Normally you could plug holes to angle mill, but the S/R heads water passages diverge under the deck surface. They are available in 67cc and manufacturer says you can only mill I think .020" off the deck. Iron Eagles are available w/ 49cc chamber, which has obvious advantages in a flat-top piston class.

Ended up buying Iron Eagles (small 180cc to be legal for class.) Nice heads! As previously mentioned, they have bronze valve guides vs. iron. Also the factory valve job was at least 5 angles on intake and 2 or 3 plus radius on exhaust with some "bowl hogging" vs. stock type valve job on S/R. No flow bench or flow data, but they look better....

Nova John
PS I just read this and it looks like I'm trying to sell these heads. No affliation with anyone, just my $.02

PRH

Post by PRH » Mon Apr 18, 2005 8:30 pm

Dart also makes an iron head that's 165cc's with the std OE style chamber and iron cast in guides, like the World S/R head, and is available in a 1.60/2.02 or 1.50/1.94 version.

we have a class in one of the local dirt series that allows the use of either the Dart or World OE type head, or an OE open chamber head. all must use the 1.50/1.94 valve sizes.

Pro Action/Top Line also has an OE replacement head like this.

Post Reply