my Low dollar 318 hop-up project

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I see guys say: I bored my *** motor .060and now I have these many cubes, it gotta go faster! where they miss the part about how an engine is a collection of parts and the key is how they work together and also with the car as to trans, converter, gears, etc. It ain't just about cubic inches.
 
barbee6043 said:
I see guys say: I bored my *** motor .060and now I have these many cubes, it gotta go faster! where they miss the part about how an engine is a collection of parts and the key is how they work together and also with the car as to trans, converter, gears, etc. It ain't just about cubic inches.
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for sure to get the most out of changes, the collaboration of parts should be picked to compliment each other.
  • Low Dollar 318 - And here I changed oil earlier and planned to drive it a bunch more, and tomorrow's September and it's been just sitting.... LOL Amazing how busy life's been in 2020 ..... WOW!
 
barbee6043 said:
I see guys say: I bored my *** motor .060and now I have these many cubes, it gotta go faster! where they miss the part about how an engine is a collection of parts and the key is how they work together and also with the car as to trans, converter, gears, etc. It ain't just about cubic inches.
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Plus heads, a 408 is gonna have a hard time making a lot more power than a stock head 318 if you also slap stock 318 heads on the 408 :)

Also people seem to figure a certain hp per cid say like 1.25 hp:cid is the same difficulty no matter displacement eg.. 273/340 hp vs 408/510 hp, obviously the head flow requirement between the two is vastly different.
 
273 said:
Plus heads, a 408 is gonna have a hard time making a lot more power than a stock head 318 if you also slap stock 318 heads on the 408 :)

Also people seem to figure a certain hp per cid say like 1.25 hp:cid is the same difficulty no matter displacement eg.. 273/340 hp vs 408/510 hp, obviously the head flow requirement between the two is vastly different.
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Won't dual quads help the 318...
 
This is a great build and i'm glad to see someone encouraging people to have fun with what they have without going broke. While ill always advocate for more inches if it is the same cost there is nothing wrong with hopping up a 318.
I grew up in a family shop that built a lot of dirt track stuff while doing general repairs and street hop ups for people.
In the early eighties the 318 pickups and cars seemed so gutless that people were unhappy with a year or two old car. These were low mileage vehicles only a few years old. The recipe I learned from my grandad was simple. Cars got a low buck sealed power 340 cam. A set of 360 smog heads milled .040,three angle valve job,steel shim head gasket.(people now days seem to claim this wont work). If the customer wanted to pay a very basic gasket matching and porting. The same cast iron 340 intake manifold or an edelbrock depending what was available. Sometimes a thermoquad,sometimes a holley economaster 4 barrel and occasionally a racier piece if the customer insisted. The lean burn ignition was replaced with factory chrysler electronic and echlin ignition box.
Pickups got the same treatment with a different cam. People raved about the drastic improvement. It always seemed these mild hop ups drove far more repeat business to my grandads shop than all of the really hot dirt track,drag and street stuff that was built. But that may be my perspective as a teenager enamored with anything mechanical.
 
HankRearden said:
This is a great build and i'm glad to see someone encouraging people to have fun with what they have without going broke. While ill always advocate for more inches if it is the same cost there is nothing wrong with hopping up a 318.
I grew up in a family shop that built a lot of dirt track stuff while doing general repairs and street hop ups for people.
In the early eighties the 318 pickups and cars seemed so gutless that people were unhappy with a year or two old car. These were low mileage vehicles only a few years old. The recipe I learned from my grandad was simple. Cars got a low buck sealed power 340 cam. A set of 360 smog heads milled .040,three angle valve job,steel shim head gasket.(people now days seem to claim this wont work). If the customer wanted to pay a very basic gasket matching and porting. The same cast iron 340 intake manifold or an edelbrock depending what was available. Sometimes a thermoquad,sometimes a holley economaster 4 barrel and occasionally a racier piece if the customer insisted. The lean burn ignition was replaced with factory chrysler electronic and echlin ignition box.
Pickups got the same treatment with a different cam. People raved about the drastic improvement. It always seemed these mild hop ups drove far more repeat business to my grandads shop than all of the really hot dirt track,drag and street stuff that was built. But that may be my perspective as a teenager enamored with anything mechanical.
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Couldn't agree more. We cut 360 heads .040-.045 without issue, ever, and always had a nice gain.
 
318willrun said:
Couldn't agree more. We cut 360 heads .040-.045 without issue, ever, and always had a nice gain.
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Late to the party. How much do you need to shave to turn them into closed chambers? And would you want to?
 
toolmanmike said:
Late to the party. How much do you need to shave to turn them into closed chambers? And would you want to?
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I, personally, think open chamber heads flow better. If I can run the same compression with a open chamber head vs closed chamber head, I'll take the open chamber.
 
318willrun said:
I, personally, think open chamber heads flow better. If I can run the same compression with a open chamber head vs closed chamber head, I'll take the open chamber.
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They probably work better as far as flame travel if you think about what happens in the chamber as soon as the spark plug fires. Closed chambers only cover half the piston and the explosion starts pushing on that half of the piston for a fraction of a second. Flat top motors with open chamber heads usually run good.
 
toolmanmike said:
They probably work better as far as flame travel if you think about what happens in the chamber as soon as the spark plug fires. Closed chambers only cover half the piston and the explosion starts pushing on that half of the piston for a fraction of a second. Flat top motors with open chamber heads usually run good.
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Also valve shrouding..... My 318's with the factory open chamber heads have always pulled harder in the rpms than the 318's with 302 heads (closed chamber). Just my experience.
 
toolmanmike said:
Late to the party. How much do you need to shave to turn them into closed chambers? And would you want to?
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If rebuilding could always use pistons with a quench pad, instead of milling the sh#t out of them.
 
318willrun said:
Also valve shrouding..... My 318's with the factory open chamber heads have always pulled harder in the rpms than the 318's with 302 heads (closed chamber). Just my experience.
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Why do all the aftermarket performance heads have a closed chamber ? :)
 
becase a closed chamber has a more compact chamber, better flame travel, with either a flat top or dished piston, less advance
tight quench with either gives detonation resistence and octane cushion
open chamber may have slightly more unsrouded valves, maybe not
they can make power runing in a stock class with good gas and where you always keep the rpm above the BMEP/ torque peak
for street NOT, you have to start making compomises that hurt the torque curve. efficiency/ mileage
That's why w put all the r&d into quench dome pistons- they flat work better
now with closed chamber heads you do not need them
The best thing to do with open chamber heads is to weld them up or cut them flat -if possible
 
fishmens67 said:
Why do all the aftermarket performance heads have a closed chamber ? :)
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I don't care if they had no chamber... lol, like I said "my experience". I know others that have experienced the same. I won't debate it :)
 
toolmanmike said:
Late to the party. How much do you need to shave to turn them into closed chambers? And would you want to?
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I got these in a lot of parts from a friend of mine.
I measured them against an un-cut set and they were milled around .125"


iLx7RH.jpg
 
318 build and break in complete!
Runs strong in the test stand....
I just finished dropping it in the truck and just going to put it through some road testing!!
This thread was what got the ball rolling!!
G

318 a.jpg


318 g.jpg


318 b.jpg


318.jpg


318 5.2.jpg
 
Elgordo76 said:
318 build and break in complete!
This thread was what got the ball rolling!!
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Also, I just want to say thanks. It's quotes like these and results you've shown that make all this worth it and so much fun, here on FABO and my youtube channel.
:thumbsup:
 
Jan 22, 2016 to present, the low dollar 318 has been reliable, fun and stout. However, it's time in the '74 Duster is coming to an ending as there is another motor on the stand that will soon (in a few months) take it's place for a complete different task.
 
318willrun said:
Jan 22, 2016 to present, the low dollar 318 has been reliable, fun and stout. However, it's time in the '74 Duster is coming to an ending as there is another motor on the stand that will soon (in a few months) take it's place for a complete different task.
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So what is it ?
 
I’m old school I guess and not a big fan of the magnum engines. I know they make great power and are roller motors and heads flow better but I just can’t give up on the LA motor. But its a Mopar and I for sure will watch and see what I can learn about the magnum motors. Can’t wait to see your plan
 
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