Dart Head Issues
#21
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Stock rockers with the rocker tray or "bridge" slightly modified on the corner tabs work out fine on those heads. Jesel shaft rockers work fine. Harland Sharp rockers work fine, and a really trick rocker by a company called Curtis Built work fine. I don't see why any rocker/shaft set-up that fits a stock head would not fit your heads???
#22
Originally Posted by rjw
Their R & D 80 sets went to various builders, none of which informed them of this or of the combustion chamber being to large for a small bore engine.
Galen
#23
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I'm sure you could just grind the crane guideplates no? You arent going to hurt them at all. I would do that before grinding on the heads.
I am a little concerned with the bore size since I am going to be using them on a standard bore motor. RJW, can youi just open up the head gaskets a bit where they are hanging over? I dont have a GM MLS gasket here to see how far you can go.
I am a little concerned with the bore size since I am going to be using them on a standard bore motor. RJW, can youi just open up the head gaskets a bit where they are hanging over? I dont have a GM MLS gasket here to see how far you can go.
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Originally Posted by Malihoochie
Stock rockers with the rocker tray or "bridge" slightly modified on the corner tabs work out fine on those heads. Jesel shaft rockers work fine. Harland Sharp rockers work fine, and a really trick rocker by a company called Curtis Built work fine. I don't see why any rocker/shaft set-up that fits a stock head would not fit your heads???
I am curious as to why the chamber is wider than our stock bore, requiring us to use .080" bigger bore gaskets than the 3.910 bore that we have. I could see this on the 225's, but on the 205's?
A fella at your location stated that 80 sets went out to R & D people, but no one gave feedback as to any issues? It seems that the only ones who installed a set and reported results, did so on 4" bore engines.
It would have been nice to know what the issues were before buying.
Now, how long will it take to get a 3.980" head gasket made from Cometic?
Vettenuts has issues with his crane rockers.
I am not unhappy with these heads, in the least, so far, but they do have some issues that people need to be aware of.
Some buyers want a true bolt on, while others (like myself) don't have a problem with having to fit things. I'v spent a bit of time deburring these heads as well. jmo
#26
Just measured my "heart width" of the chamber, it is approxmately 3.96" leaving about a 0.030" overhang above the 3.9 bore. Will this matter in any way?
Just found this statement by Brian Tooley:
"Just had a chance to flow the new TFS LS1 head, it has a 13.5 degree valve angle and relocated spark plug to enhance the mid lift flow with a smaller valve, these had 2.04/1.57 valve diameters. This is the most impressive head we have seen on a 3.90 bore. The chamber measures around 3.950" across, so it is designed to be optimum on a 3.90 bore."
in this thread.
Not sure I follow the reasoning behind Brian's statement as to why the slightly larger chamber cross measurement is optimum. I am confused again, but that's nothing new
Just found this statement by Brian Tooley:
"Just had a chance to flow the new TFS LS1 head, it has a 13.5 degree valve angle and relocated spark plug to enhance the mid lift flow with a smaller valve, these had 2.04/1.57 valve diameters. This is the most impressive head we have seen on a 3.90 bore. The chamber measures around 3.950" across, so it is designed to be optimum on a 3.90 bore."
in this thread.
Not sure I follow the reasoning behind Brian's statement as to why the slightly larger chamber cross measurement is optimum. I am confused again, but that's nothing new
Last edited by vettenuts; 12-28-2005 at 07:41 PM.
#27
Originally Posted by Slowhawk
Vettenut's,also what CC are these heads? With your cam you want good compression to get the most out of them.I would look for 60-62cc if there is enough P/V clearance. Mill them now rather than kick yourself later
Last edited by vettenuts; 12-29-2005 at 07:40 AM.
#28
Originally Posted by rjw
I am curious as to why the chamber is wider than our stock bore, requiring us to use .080" bigger bore gaskets than the 3.910 bore that we have. I could see this on the 225's, but on the 205's?
#29
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The chambers measured and are advertized as 62cc's...Mine are currently around 63cc's cleaned up.
I haven't yet trial fit these heads to the block, so until then, I won't make a decision on the gaskets.
Remember that the very top of the cylinder has a fairly hefty chamfer, which means that a small portion of a 3.910 gasket would be left unsupported around the entire cylinder, even with a smaller chamber head.
BTW No comments on my chamber clean up?
I haven't yet trial fit these heads to the block, so until then, I won't make a decision on the gaskets.
Remember that the very top of the cylinder has a fairly hefty chamfer, which means that a small portion of a 3.910 gasket would be left unsupported around the entire cylinder, even with a smaller chamber head.
BTW No comments on my chamber clean up?
Last edited by rjw; 12-28-2005 at 09:45 PM.
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RJ
Are you saying that the " gasket overhang" is OK???. I have not noticed the head gaskets with the stock heads to see if there is an issue, but I would think that it would cause gasket failure sooner or later.
Dart tech... Any comment on this??
By the way RJ, Nice looking CC. If I send my heads down, will you work my up like that??
Are you saying that the " gasket overhang" is OK???. I have not noticed the head gaskets with the stock heads to see if there is an issue, but I would think that it would cause gasket failure sooner or later.
Dart tech... Any comment on this??
By the way RJ, Nice looking CC. If I send my heads down, will you work my up like that??
#31
Originally Posted by rjw
BTW No comments on my chamber clean up?
Does anyone know the chamber width of other heads, stock, AFR, etc.?
What is the diameter of the stock head gasket, is it exactly the bore diameter? I don't have mine yet.
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The OEM MLS gasket is too small, so I will probably be going with Cometic 4.13 bore gaskets. Dart recommended this as well.
My stock 241's measured between 3.904 and 3.908"
My stock 241's measured between 3.904 and 3.908"
#38
I am really not very concerned about head gaskets...I will purchase whatever I need. What I am concerned about is if it will be detrimental for the cc to overlap the cylinder bore like it appears it will. Maybe I am making a mountain out of a mole hill…but I would like to hear from some of our more experienced engine builders on this one.
Thanks ya’ll!
Galen
Thanks ya’ll!
Galen
#39
Galen,
Saw your post on the Dart Board and was surprised at the answer provided by Dart. I have a post in the Advanced Section on this, but as of yet no responses. It appears the Dart and TFS combustion width is the same, so I was wondering if there was something to this, but based on the Dart Response on their web site, I guess not
Saw your post on the Dart Board and was surprised at the answer provided by Dart. I have a post in the Advanced Section on this, but as of yet no responses. It appears the Dart and TFS combustion width is the same, so I was wondering if there was something to this, but based on the Dart Response on their web site, I guess not