360 build ????s

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Well, I played around with the Dcr calculator, and it turns out, you'll probably be allright; so long as the valves dont get into the pistons.
Unfortunately there may be very little to no quench or squish, so you may be stuck running premium, even though your Dcr is in the ballpark. Guess we'll see. Good luck

My dad and I figured it would end up being a premium only motor this way. Which is ok. Better than expensive race fuel. Thanks again for the help and info!
 
Alright, i have been assembling the motor. My main worry was piston to valve clearance. Well, that is the issue. Here is the full combo.

318/4 speed/8.75 with 4.11 gears
Stock rotating assembly
Purple shaft 284/484 cam
J heads that have been ported, milled .100, and the large valves installed. I bought the heads at a swap meet. Lack of knowledge and didn't see the milling job.
Stock length push rods and rocker shafts
Head gaskets are Felpro from a full gasket kit from Summit(number on the gasket is 8553PT)
Torker II 340 intake

What are my options with this setup? I am keeping the cam and intake.

I have read and been told thicker gaskets won't get it done. True?
Spacers on the rocker shaft???? Seems odd but an option?
Shorter push rods
Best to go with different heads??
 
What i would do is stop fooling around and save up for a proper build.
Take those heads and put them on the swap meet table and get rid of them like the last guy did to you.
Put the Torker II on the table and get rid of it too.
Buy a air gap intake and install headers.
Both will compliment the next build and will be 100% transferable.
You are over thinking this big time.......
 
BTW, i am running a purple shaft 484 cam in my '79 360 with about 8.2:1 compression, stock 1.88 intakes, a weiand dual plane action plus intake, a 625 edelbrock carb, 340 exhaust manifolds with dual exhaust and 3:55 gears with a 4 speed in my '74 Dart Sport.
It sounds good, doesn't make a lot of power really, but is dead nuts reliable.
On a compression test to see what the cylinder pressures were, it was about 130 lbs per cylinder (lousy), and all were equal.
Keep in mind, i threw this together with what i had until i could afford to build a proper engine. It does not use or leak any oil.
I'm happy with it for what it is.......
 
Run the mp cam. My 340 dart ran a best of 13.15 with the mp 280 cam. Switched to a 276 voodoo best time was 13.13 Not what I expected. Maybe the 280 just fit my combo better.

I find it interesting that you went to a smaller cam with 11 degrees less intake duration and 5 degrees less exh duration, but ran almost the same et.
 
I know the Torker II is not the best intake out there. I am using what I have at the moment. The "proper build is not in the books right now. the 318 was in the car and had a flat cam. I want to throw some pep at it and this is the cam I want. I found these heads at a swap meet and missed the shaved portion of them. My bad. All I have into this build is my time and the money for the cam setup, gaskets, and the heads. I only paid $325 for the heads with adjustable crane rocker setup. I chose to not use the rockers so sold them. So the head to me were basically free and I know I can salvage some funds back out of them if I want to. The 360 option I talked about initially was not going to work for me at the time and still doesn't.

I guess a question I can ask is. The heads I took off the 318, can I take the double springs from the J heads and install on these? Or do the larger valves on the J heads and smaller valves on the 318 heads make this not happen?
 
318 heads and J heads can use the same size springs, the valve size difference is only the head diameter, lengths are approximately the same. a .484" lift flat hydraulic lifter cam does not need double springs. now do not just throw the outer springs from the J heads on the 318 heads, they will probably be too weak. and the double springs may need to have the 318 heads step cut for the inner spring and may be too stiff for the cam. can u tell if the intake sides of the J heads have been cut so the intake will fit?
 
Yes the intake side of the J heads have been cut. Will the stock 318 heads work then if I just bolt them on? Some say you don't need the double spring. Then some do and so does the cam specs. I am just trying to learn is all and get my motor together. So many different variables and opinions that people have. I am just trying to find out what to do to make my current application work or if I am better off just going with a different set of heads. How do I know what springs to purchase for this cam?

I have a local Mopar guy that I am calling tomorrow since today is fathers day. Possibly just do some swapping for the correct head setup that hasn't been shaved. LOL.
 
used stock springs are no good for .484" lift. the spring mopar recommends for the 284/.484 cam is p4120249 or equivalent - a single spring with dampener. stock 318 pistons are below deck. I question a guy selling heads bragging they have been cut .100" , they would then be closed combustion chambers or very close to closed. can u post pics? I would set the J heads on the block with head gaskets and see how the intake fits. if it fits throw the heads on with a few bolts and no head gaskets and check if the valves clear the pistons and cylinder walls with the new cam (this needs to be done with 2 solid lifters). should have kept the adjustable rockers
 
cdavis. The voodoo 276 is 234 in. 242 ex. at .050 lift .513 in. .533 ex. Mp 280 is 234 at .050 and .474 lift. So I figured the new faster profile would be quicker. Sometimes it doesn't work that way. Just my experience. I know other have had great success with the voodoo cams.
 
I am working on trying to get pics posted. I did not measure the P to V clearance by how many would do it. I used the playdoh method. they clearly hit the piston. Intake only is hitting. Also so the question isn't asked it was turned over by hand. I checked the 1,3,5,7 side. All four are hitting the same way. With head gaskets and everything torqued to spec.
 
I am working on trying to get pics posted. I did not measure the P to V clearance by how many would do it. I used the playdoh method. they clearly hit the piston. Intake only is hitting. Also so the question isn't asked it was turned over by hand. I checked the 1,3,5,7 side. All four are hitting the same way. With head gaskets and everything torqued to spec.


This is with the new cam installed also. This motor would be assembled and running if I hadn't went with these heads. Oops.
 
Yeah I just used what I had at the time. When there was a whole in the playdoh, that was enough to tell me there isn't an clearance. Haha
 
Alright, i have been assembling the motor. My main worry was piston to valve clearance. Well, that is the issue. Here is the full combo.

318/4 speed/8.75 with 4.11 gears
Stock rotating assembly
Purple shaft 284/484 cam
J heads that have been ported, milled .100, and the large valves installed. I bought the heads at a swap meet. Lack of knowledge and didn't see the milling job.
Stock length push rods and rocker shafts
Head gaskets are Felpro from a full gasket kit from Summit(number on the gasket is 8553PT)
Torker II 340 intake

What are my options with this setup? I am keeping the cam and intake.

I have read and been told thicker gaskets won't get it done. True?
Correct
Spacers on the rocker shaft???? Seems odd but an option?
Not an option
Shorter push rods
Yes but
Best to go with different heads??
Maybe

If the heads and intake will all bolt up without more machining, its just a matter of fixing the P to V clearance, and then sciencing out the valve geometry.
You will of course need to calculate the eyebrow depth of cut, and then measure the piston tops before you cut the eyebrows to ensure there is enough material to allow the cut without compromising the integrity of the piston.
If the piston tops wont allow it, then you have exactly 2 options; 1) smaller cam with lift engineered to work, or
2) different heads.
But as someone else posited, if the heads have been machined .100, and are now as good as closed chambers, it would seem a waste not to at least try and make things work. There are pistons out there that already have eyebrows, and have thick tops, that could be made to work. And since the engine has to be mostly dissassembled to measure the current piston tops, you are nearly ready to repiston anyway.
And if you go with new pistons, you can engineer quench and squish back into it, and possibly/probably get it to run on lessor fuels.
I say its an opportunity.
 
I talked to my local go to Mopar guy. He said two options.

- Special head gaskets that can be ordered per request but cost $3-400. Not an option IMO. He also recommended not doing this.
- Cut the pistons

I decided I am going to just go with a different head. He has a set of 360 heads that he will install the proper springs on for this cam. If he is not interested in my J heads, I will just sell them. I know there are a million different directions to go but after all it is only a 318. So I do not want to stick a few hundred dollars more into pistons that will work. I am still on invested in this setup for around $500 and my time. In the future the proper build will be set in place on paper pre purchase and assembly. whether it is a small block or a big block. I haven't totally decided yet.

Once again, THANKS to all that have shared there input. I appreciate it and know I irritated the heck out of most of you. LOL.
 
The shaved heads should keep some compression in that mill, which is what the 318 really needs. Notching the pistons should be a relatively easy affair. As others have said, the cutter can be rented and a careful setup (After determining the depth needed) can yield good results in your garage. Heck, super glue and sand paper can make it work.
 
UPDATE

My 318 turned out to be in good shape to just do a cam swap. I ended up trading the milled out J heads for some Non milled J heads with bigger valves. I am hoping here in the next few days to finally fire this thing up. I just have a few questions to ask prior to firing. Full motor info......
78 318 with J heads that have larger valves, purple shaft 284/484 cam, Eddie carb(1406 number is on it, idk cfm), Torker II intake, Hooker headers(El cheapos), otherwise all stock from there.

1. I Installed a Holley Blue electric fuel pump. What should I set the fuel pressure to to start with? I installed 3/8" fuel line also.

2. Good base point for timing? Stock electronic ignition.
 
Well the car has been running great. Although the passenger side exhaust(true duals) smokes quite a bit and leaves oil spatter under the car. Was told the intake is not sealed good inside. So today I pulled the intake and found a rocker arm failed and the push rod was through, which also wrecked the lifter. this must have literally just happened. Weird part is I had no signs of issues. Good oil pressure, no misses and no knocks. I will get this all fixed up in the next few days. While playing on craigslist I ran across an ad for a Victor 340 racing aluminum intake.

Would this be an upgrade from my Torker II 340 intake?
I looked the specs up and says 3500-8000 rpm. Seems excessive for my setup on the top end for sure. Just curious if would be worth my time to see how cheap I can get it for. Says make an offer. LOL.

I did not intend to look to upgrade my intake but since it is off and the oppurtunity is there figured I would check. I did reread this whole post from everyone for intake info. this one was not listed but just curious is all. Not sure if I will spend the money or not.
 
For a street car I would think a nice dual plane would be more appropriate for throttle response and all.
 
Not an expert here, but everything you are doing is adding up to a lot of rpm I think. I have that cam in a 360. It really likes light springs for advance, at least mine does. Might want to list listen to Bad sport with the intake, I am running an air gap. With that cam you probably want a dual plane for street use.
 
I don't think you could have mismatched parts any worse than if you tried.
 
Thanks guys. All I needed to know. Don't need any insults by any means. Everyone's a critic. I know it isn't the "perfect combo". As I have stated in prior comments I am using what I have available since it is only a 318 and not worth big money. I wanted the cam I chose since I know it works. The car runs great and performs well for the street and what I want at the moment. Thanks again Badsport and 1973 barracuda.
 
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