my Low dollar 318 hop-up project

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If the 360 head is a 974 casting, it can done to work great, if it's not I would stick with the 318 heads and do the work I illustrate in my 318 porting for the average joe sticky.

I even added another casting, flow numbers and pics a couple days ago.

I'll look into it for sure, thank you.
 
if the 360 is a good motor, I would probably use it. You'd have more low end torque and power. You may give up a mile or two per gallon... but not if you are pulling.

That was actually my original plan, I guess I'll have to take a close look and see if its a usable engine. Thanks again.
 
My 68 3/4 power wagon with 318, 2 bbl, 4 sp, 4.10 gears and 9.50-16.5 tires pulling a loaded 4 horse trailer got 8 to 10 mpg.
Swapped to a 76 360, 4bbl and gained more pulling power and 2 mpg.

55 mph is my max speed for hauling loaded with animals on the hiway.

Lol 8-10 mpg seems about what I get loaded or not. I have the 4:10's as well with 727 with np205. I use it to carry heavy loads and to get from here to there once in awhile.
 
Part of that is the 4 brl will always get better mileage than a 2brl...unless its TINY...is because the front primary venturi of the 4 brl is smaller and mixes 'with the higher velocity' fuel better.
My 68 3/4 power wagon with 318, 2 bbl, 4 sp, 4.10 gears and 9.50-16.5 tires pulling a loaded 4 horse trailer got 8 to 10 mpg.
Swapped to a 76 360, 4bbl and gained more pulling power and 2 mpg.

55 mph is my max speed for hauling loaded with animals on the hiway.
 
Thats why a TQ works so well
pick the small or large primary depending on being able to run on the primary most of the time
otherwise spread bore AVS
let's not just pick on total FPS out on primary flow
 
if the 360 is a good motor, I would probably use it. You'd have more low end torque and power. You may give up a mile or two per gallon... but not if you are pulling.

Apples to apples comparison.
My dad has a w150 extended cab 360 4-speed 3.55 gears 14.5 mpg. He documented every gallon of gas he put in it since new.
I had a w150 318 4-speed 3.55 gear shortbox truck 14.5 mpg.
The 360 is a way better truck engine.
Both trucks are 1978.
 
If the 360 head is a 974 casting, it can be made to work great. If it's not... I would stick with the 318 heads and do the work I illustrate in my 318 porting for the average joe sticky.

I even added another casting, flow numbers and pics a couple days ago.
What makes the 974 head more desirable than other J heads for a 318 swap? I've done some searching but wanted to ask while this post is still somewhat current.
 
What makes the 974 head more desirable than other J heads for a 318 swap? I've done some searching but wanted to ask while this post is still somewhat current.
They're on the small side compared to other castings, port volume is usually around 150cc and the exhaust ports, 'smaller than a j head exh port l' but with a lot better shape qith a raised floor. J head is a great head, for a 340/360.

People lump them all together because they tend to overlook or are ignorant to the small , but quite significant... and mostly people judge them by max potential or by them flowing within 10 cfm as cast..."same size valve"..ill also add that MOST who tried a set of ported factory iron didnt have the right person performing the porting.
Sadly most who fall into that group, for that reason, will never try another set thats actually done right...in their mind they tried it and it wasnt all that.... but neither was their head porter.
 
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I want to say what a great thread with a lot of good info. Since reading this I started porting some magnum heads. I don't think the screwdriver is going to make it through the port though
 
I want to say what a great thread with a lot of good info. Since reading this I started porting some magnum heads. I don't think the screwdriver is going to make it through the port though
Your post is the exact reason I did the project. Thanks for the kind words, and happy I inspired you to try it. Every porter did their first port job at some point. Wishing you the best with your project!
:thumbsup:
 
Your post is the exact reason I did the project. Thanks for the kind words, and happy I inspired you to try it. Every porter did their first port job at some point. Wishing you the best with your project!
:thumbsup:
Changed your avatar after all these years. I like it.
Is that a car you once owned ?
 
Got my Accel dual point distributor (20301 :) ) and Super Coil in the mail today.... I'll see how close it comes to the fire wall.
 
Believe it or not, I was thought to be young kid by some because I had a toy in my avatar
:lol:
LOL I thought you were a kid when you joined and started appearing in the chat room. lol
I thought you were Asa's young buddy recruit. lol
 
LOL I thought you were a kid when you joined and started appearing in the chat room. lol
I thought you were Asa's young buddy recruit. lol
That right there is funny...... Asa lived there... Rani.... 70Aaarcuda.... RRR.... now I miss it :(
:rofl:
 
I hate it when someone changes their avatar. Don't recognize them. You did it too... lol
galleryimage_image_198.jpeg

Everybody thought I was some young guy and that this was my picture LOL
It's from the movie vanishing point I think..
 
LOL I thought you were a kid when you joined and started appearing in the chat room. lol
I thought you were Asa's young buddy recruit. lol
I am young though... make no mistake about it! :D :D Been in this game a long time because I bought my first car, a '72 Duster, when I was 14. I gave 350 dollars worth of guns and had to make payments on the last 150 :D :D :D
:thumbsup::thumbsup:
 
You know you are OLD when you are older than the cars you restore!!??????//// I need some cars made back in the 40's! so I can feel young again!!!????/
 
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