Hot Rod Forum banner

283 head gaskets

13K views 14 replies 6 participants last post by  techinspector1 
#1 ·
I have been reading up on head gaskets because I am almost to the point of putting on the heads on my 283 build. I know the pistons are shorter than stock. I have decked the block and the heads for a total 0f .017 (.010 block .007 heads). My kit came with a composite (cheap looking) head gasket and I don't know what the compressed thickness is. I am guessing .041. I have read that we want a quench of about .041. Doing the math, if I use the .041 gasket I will have a quench distance of .056. Is that too much? I am going out to try to measure the top of piston to deck height soon to confirm my numbers.

Also if I use the composite gaskets do I spray them with copper seal or put them on dry?

What is the best head gasket to use?
 
#3 · (Edited)
I have been reading up on head gaskets because I am almost to the point of putting on the heads on my 283 build. I know the pistons are shorter than stock. I have decked the block and the heads for a total 0f .017 (.010 block .007 heads). My kit came with a composite (cheap looking) head gasket and I don't know what the compressed thickness is. I am guessing .041. I have read that we want a quench of about .041. Doing the math, if I use the .041 gasket I will have a quench distance of .056. Is that too much?
While 0.035" to 0.045" is considered by many to be ideal, the motor will work fine with a slightly wider squish of 0.056" in my opinion.

Also if I use the composite gaskets do I spray them with copper seal or put them on dry?
Clean all foreign substances off the block deck, heads and gaskets and install them dry.

What is the best head gasket to use?
The best gasket to use is the one that works with your combination. With iron heads, use just about any gasket you want to. If the block decks and heads are flat, you can use shim gaskets (0.016") if the decks and heads are flat within 0.002" end to end. Composite gaskets will allow a good seal on "less than ideal" surfaces because they have the thickness to conform and still seal. Those fellows with aluminum heads have to use a thicker composite gasket (0.039"/0.041") with a pre-flattened fire ring to prevent brinelling of the aluminum.
With iron heads on a 283 where I needed a little thinner gasket, I'd use this one.....You can buy it here from Summit or you can toddle down to your local Chevy dealer and order it across the parts counter. Note that they are sold individually.
Chevrolet Performance Composition Head Gaskets 10105117 - SummitRacing.com
If your pistons are down in the hole by 0.017", these gaskets will yield a squish of 0.045".

One part of engine assembly that always makes me grit my teeth is the installation of the intake manifold. If the block decks are not parallel with the main saddle on all four corners, the heads will not sit squarely on the decks and the intake manifold will not seal the same all the way around. Pay very, very, very close attention to the intake gasket seal. I have even sacrificed a set of intake gaskets by installing the manifold, torquing to specs, letting it sit overnight, then removing it to inspect the gaskets for being pinched ALL THE WAY AROUND EVERY PORT. If you put the motor together with an internal leak at the interface of manifold and heads, it will never be right and could possibly suck oily vapors from the crankcase into the port and on into the cylinder as the piston descends with the intake valve open. Just PAY ATTENTION. Many builders miss this very important step.
 
#5 ·
I think the biggest problem here will be finding a "dedicated" gasket for the 283. Virtually NO ONE makes them in under a 4 inch bore, unless you go with the racing/specialty aftermarket ($$$$). I just got lucky, and found a NOS complete gasket set for a 283, including steel shim head gaskets. Butch/junior stocker.
 
#6 ·
Mertz has bored the block +0.030", so the new bore is 3.905". At the very top of the bore, the machine shop would have cut a chamfer to ease entry of the rings into the bore. I have no idea what the O.D. of that chamfer is, but a WAG might be 3.930". That'll leave 0.035" difference between the gasket and the bore on the radius. Close enough in my opinion.
 
#7 ·
I ordered the kit for a 283 and hoped the gaskets were for the 283. I haven't measured them yet but they had a part number on them. First a cirle with a V in it and then 2995. techinspector is correct that the cylinders are 30 over and the tops have been chamfered. I will measure that as well this evening.
 
#11 ·
I have read a lot of techinspector's recommendations and trust that he knows what he is doing. I will probably order the head gaskets he recommends but I am going to check with a local engine builder and see if I can fine one close to the 283 bore. I am also going back to the person I bought the kit from and see he has anything to offer about the 283 kit he sold me.
 
#13 ·
I ordered the gaskets techinspector recommended. I checked the depth of the piston and it is .030 down. I also looked at the old gaskets and they are the same as the ones I have that are too big. The quench should be about .058 with these gaskets.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top