Visit The Dirt Forum for More Information

Author Topic:   49cc Iron Eagles
Rollin Thunder
Member
posted October 07, 2003 06:25 PM
I dont think you would have enough room in the chamber to do so, I just finised a 383 for a guy with the 49cc heads and flat tops, and I had to run .020 shims under the head gaskets to make enough room. One thing I can tell you is that you more that likely will have to grind on the push rod holes on the intake sides to clear the intake ports


sbateman
Member
posted October 09, 2003 10:27 PM
i run a 350 flat top at 0 deck height /with 49cc iron eagle and a 575 lift cam , had to flycut the pistons (srp) 50 thousands to get 120 on my exhaust


waltonjr1
Member
posted October 09, 2003 11:45 PM
Are these heads worth the trouble?It seems like you will lose the compression you gain by going w/ the small chamber if you must flycut the piston or shim the head?I was thinking about trying these heads if there worth it.Anybody else use these heads without making modifications?

------------------
DEANJR#22


sdhnc29
Member
posted October 10, 2003 12:57 PM
Yes you can run a small dome up to .150" without modifications . Anything over .150" and you will need to notch the piston dome to clear the spark plug area inside the chamber . You will also need to use a question mark shaped dome , not a concentric dome .

Steve

------------------
Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


Rollin Thunder
Member
posted October 10, 2003 06:20 PM
The question mark dome is shaped similar to a question mark ( ? ). This type of piston is designed for a modern style combustion chamber , such as the Dart , that has the intake side of the chamber laid back . A concentric dome is simply that , concentric . The dome goes straight across from intake to exhaust . This style dome is compatible with very old race heads and stock production heads .

I don't believe that Speed-Pro makes a question mark dome on any of their pistons , so you would most likely have to modify the piston to clear the spark plug area in the combustion chamber .

As for brands of pistons that make this style dome , you can check with JE , Weisco , CP , Ross , etc. Pretty much any of the major piston manufactures make this style dome . It will just be a matter of finding the correct one in the price range that your looking for .

Steve

------------------
Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


hiway80
Member
posted October 13, 2003 09:34 PM
I bought a set of these heads a few months ago and warned everyone then about these heads. I called dart and they were very little if any help. Dart told me that they were a new casting, but after doing some research I found that these heads are only angle milled from the factor. I called dart and asked if they could be milled more and they told me .030, my machinist said no way. He said he would get into the intake seat.

Iím getting close to 13:1 compression with flat tops, no need for dome pistons. Good Luck with them.


Back to the Archives