318 with 360 heads and compcam build help

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CLAY72dart

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Alright here is how my story goes I have a 67 318 with 318 heads and a spare set of 360 heads practically stripped to nothing all I know I need is valves to put these on pictures below are of the cam kit I have in a box for the car and the cam spec sheet. Looking for advice I’m keeping the stock crank and connecting rods other than that it’s free game. Ignore the pushrods didn’t know enough when I bought that about a year ago. I’m thinking I can use the original pushrods and rocker assembly on the 318 heads but I’m not sure I don’t have a spec sheet for something like this.
IMG_2322.jpeg

These are the 360 heads with nothing on them
IMG_2319.jpeg

This is the 318 heads I have with everything on them.
Intake. Exhaust.
VALVE ADJUSTMENTHYDHYD
GROSS VALVE LIFT• 497. 483
DURATION @
- 006 TAPPET LIFT287304
VALVE TIMING
.006
Open CLOSE

INT: 40.0
BTDC67.0
ARDC -
EXH :80.0BBDC45.0
ATDC
THESE SPECS ARE FOR CAM installed
@ 102.0 INTAKE CENTER LINE
INTAKEEXHAUST
DURATION @ . 050235249
LOBE LIFT• 3310• 3220
LOBE SEPARATION107.0
Don’t know what this chart really means. But this is what I bought a while back on marketplace.
Looking for help on what to buy to build the block I can answer your questions If you can help me choose what to do to make some power.

IMG_2321.jpeg
 
Here’s the list you have to awnser get the best responses.

What car is it going in.
What kinda driving. Street / Strip, only strip, AutoX / canyon carver
What are your goals for car
What transmission, gear ratios. If auto, what’s the converter specs.
What rear gearing
What tire size

Building a motor around a cam selection is not a good idea. Unless you want a dyno queen and then a dog in your car…
 
It’s going in a 70 swinger I just want to be able to get on it in a straight line from a stop or a roll. I would like to keep my 904 auto trans and I have an 8 3/4 stock rear.
Building a car around a cam isn’t a great idea but it’s the situation I’ve got myself in. I’m just wondering what else I need to do top end to get it running well.
 
Willing to buy a higher stall converter for the cam I just dont know what will be best, and I dont want to just keep buying parts I dont know will work if that makes sense.
If I read it right (and it wasn't easy reading....)
You'll need, in the very least, a good converter and some gears for that cam. Like a 9.5" converter that flashes up to at least 3800 rpms and something around 3.9 or higher gear ratio. That cam with 360 heads would appreciate better pistons for more compression as well. You put that cam with 360 heads on your 318 with stock converter and 2.76 gears, I'll smoke ya with my slant six truck ... lol.

Much cheaper to sell the cam and buy another one that fits your build. 235/249 @ 050 is a bit heavy for your build if I understand your build correctly (which I may not)
 
It’s going in a 70 swinger I just want to be able to get on it in a straight line from a stop or a roll. I would like to keep my 904 auto trans and I have an 8 3/4 stock rear.
Building a car around a cam isn’t a great idea but it’s the situation I’ve got myself in. I’m just wondering what else I need to do top end to get it running well.
Stock had different ratios. Have to mark both wheel and drive shaft, then spin the wheel and count how many times the drive shaft moves. Ie one wheel spin the drive shaft moves 3.5 or 3.2 or 3.7 or 3.9
 
That cam has a LOT of duration at .050! If you must use that cam then you're going to need 3.91 gears, or higher (numerical), and a higher stall converter. The car will not idle in gear with that cam and a stock torque converter. Regarding the head choice, 318 heads will run out of steam right about the time that cam is going to start pulling. The 915 heads with 1.88/1.60 valves would be the better choice. Depending on the current cc on the 915 heads, you will need to mill them to get some sort of compression capable of supporting that cam. How much to mill the heads depends on what piston and its compression height. If you try to slap it all together without doing the above, you'll have a dog of a combination that you'll be very disappointed with. My suggestion, if your low on funds, is to sell what you currently have and buy a complete good running stock 360, slap a cheap used aluminum intake, a 4 barrel and add headers. You can use your current drivetrain and the car will be plenty peppy and you can upgrade over time. In my area, running 360LA motors go between $400-800. You'll spend way more than that trying to get the 318 built with the parts you have, and the 360 with above bolt-ons, will smoke your desired 318 combo. Just my .02 worth.
 
Those heads will hurt compression ratio, and that cam will not like that
 
Sell the cam for a more suitable cam.

Or spend a bunch of money to make it work.

KB has a small domed piston In a Hyper or forged that will make some compression for you and will work with a 360 head.
 
That cam has a LOT of duration at .050! If you must use that cam then you're going to need 3.91 gears, or higher (numerical), and a higher stall converter. The car will not idle in gear with that cam and a stock torque converter. Regarding the head choice, 318 heads will run out of steam right about the time that cam is going to start pulling. The 915 heads with 1.88/1.60 valves would be the better choice. Depending on the current cc on the 915 heads, you will need to mill them to get some sort of compression capable of supporting that cam. How much to mill the heads depends on what piston and its compression height. If you try to slap it all together without doing the above, you'll have a dog of a combination that you'll be very disappointed with. My suggestion, if your low on funds, is to sell what you currently have and buy a complete good running stock 360, slap a cheap used aluminum intake, a 4 barrel and add headers. You can use your current drivetrain and the car will be plenty peppy and you can upgrade over time. In my area, running 360LA motors go between $400-800. You'll spend way more than that trying to get the 318 built with the parts you have, and the 360 with above bolt-ons, will smoke your desired 318 combo. Just my .02 worth.
I have an aluminum intake 4 barrel carbs headers and a 360 block sitting at the house also. It just a stripped block so I would need to buy a rotating assembly and the rest of the top end maybe I could get one on Facebook cheap.
 
Stop buying parts on Facebook with no direction.
Find and hire a reputable mopar engine builder/machine shop in your area preferably that has a dyno. Buy quality parts at the discretion of your engine builder and install/use to the manufacturers recommendation. Stay engaged with the builder to ensure you get the end result you want and don't lose interest or feel like it's not "your" project.

Don't go down the rabbit hole of spending money on parts only to become frustrated and end up rebuilding the engine twice at a significantly higher cost.
 
Cam is way wrong for combo and intended use.

Stop buying parts on Facebook with no direction.
Find and hire a reputable mopar engine builder/machine shop in your area preferably that has a dyno. Buy quality parts at the discretion of your engine builder and install/use to the manufacturers recommendation. Stay engaged with the builder to ensure you get the end result you want and don't lose interest or feel like it's not "your" project.

Don't go down the rabbit hole of spending money on parts only to become frustrated and end up rebuilding the engine twice at a significantly higher cost.


Best advice of the year.

/thread
 
Clay, what rear gears do you have or intend on using?
 
There really should be a more detailed description of what the OP is after.

Then…….. a budget.

Then start thinking about buying parts.

Great advice in post 15.
 
a competition cams 260H or xe262h (plus their spring kit) and you can use the stock converter. I hope your plan is to get the block and heads freshened up at a machine shop. I would use the 360 heads and get some domed pistons as rumblefish mentioned. Then work from there with the shop to tune in compression.
 
Alright here is how my story goes I have a 67 318 with 318 heads and a spare set of 360 heads practically stripped to nothing all I know I need is valves to put these on pictures below are of the cam kit I have in a box for the car and the cam spec sheet. Looking for advice I’m keeping the stock crank and connecting rods other than that it’s free game. Ignore the pushrods didn’t know enough when I bought that about a year ago. I’m thinking I can use the original pushrods and rocker assembly on the 318 heads but I’m not sure I don’t have a spec sheet for something like this.View attachment 1716382459
These are the 360 heads with nothing on them
View attachment 1716382461
This is the 318 heads I have with everything on them.
Intake. Exhaust.
VALVE ADJUSTMENTHYDHYD
GROSS VALVE LIFT• 497. 483
DURATION @
- 006 TAPPET LIFT287304
VALVE TIMING
.006
OpenCLOSE

INT: 40.0
BTDC67.0
ARDC -
EXH :80.0BBDC45.0
ATDC
THESE SPECS ARE FOR CAM installed
@ 102.0 INTAKE CENTER LINE
INTAKEEXHAUST
DURATION @ . 050235249
LOBE LIFT• 3310• 3220
LOBE SEPARATION107.0
Don’t know what this chart really means. But this is what I bought a while back on marketplace.
Looking for help on what to buy to build the block I can answer your questions If you can help me choose what to do to make some power.

View attachment 1716382460

First you need to decide what you want out of your car. What do you want to do with your car street car, highway cruiser, drag race? Have you driven or rode in a 340 car? Is that what you want or are you willing to put up with a lot of extra stuff dealing with a race motor? Unmilled J heads are around 73cc and unmilled 68-72 heads are about 68cc. What gas do you want to run regular or pump premium? Now you can decide on a compression ratio and buy pistons accordingly. 340 cams are in the 212-222 range of duration and .450 lift. That will put you in the 14-13 second range in the quarter mile.
 
a competition cams 260H or xe262h (plus their spring kit) and you can use the stock converter. I hope your plan is to get the block and heads freshened up at a machine shop. I would use the 360 heads and get some domed pistons as rumblefish mentioned. Then work from there with the shop to tune in compression.
Can I use the spring kit I currently have and just buy the cam mentioned?
 
First you need to decide what you want out of your car. What do you want to do with your car street car, highway cruiser, drag race? Have you driven or rode in a 340 car? Is that what you want or are you willing to put up with a lot of extra stuff dealing with a race motor? Unmilled J heads are around 73cc and unmilled 68-72 heads are about 68cc. What gas do you want to run regular or pump premium? Now you can decide on a compression ratio and buy pistons accordingly. 340 cams are in the 212-222 range of duration and .450 lift. That will put you in the 14-13 second range in the quarter mile.
I want a street car and I’m not looking to go super crazy on a performance motor I just want to get good pistons and a good cam for my 318 I would really like to put the 360 heads to good use. I have never built a performance motor just rebuilt stock motors with stock parts.
 
Can I use the spring kit I currently have and just buy the cam mentioned?
I don’t know what you plan to use for springs but the comp 901-16 or hughes engines springs HUG 1110P will fit your 360 heads with no machining required.
 
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