Probably a Dumb 318 Question

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I don’t even know where my nearest track is barona? junkyardhero probably knows but I’m looking to have a better sounding and out preform my brothers 350 nova we don’t know what’s done to the engine but it’s quick and sounds pretty good but I really don’t know what’s been done to it TH400 shift kit but at some point I’d chassis Dino to see what I’m making and at some point take it to the strip wherever that is
 
Joey N said:
I don’t even know where my nearest track is barona? junkyardhero probably knows but I’m looking to have a better sounding and out preform my brothers 350 nova we don’t know what’s done to the engine but it’s quick and sounds pretty good but I really don’t know what’s been done to it TH400 shift kit but at some point I’d chassis Dino to see what I’m making and at some point take it to the strip wherever that is
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Your brothers 350 nova? Shoot, a 318 2bbl and your good... done that 200 times back in the day... LOL
:lol:
 
Joey N said:
I mostly drive within my town which is pretty small but sometimes do freeway so I was thinking 3.73 is a good middle ground
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People may hate this but, my other car is an 86 Mustang GT 5.0 with 2.73s and 5 speed. I can take that car anywhere highway trips cruises etc. That is just a plain old light weight 200 horse daily driver type fuel injected v8 car.
 
Joey N said:
I was thinking 3.73 You know the Chevy gears
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Small displacements really needs gears to work, To me one of the main advantage's of larger engines is that they require less gearing and stall speed. 3.73 would be a decent gear definitely wouldn't go less.

Eg. Say a 12's @ 110 mph A Body makes 400 hp at these rpms for each cid 273 @ 7000 rpm, 318 @ 6000 rpm, 360 @ 5300 rpm and 440 @ 4350 rpm. Would need these gears with 27" tire to hit peak hp @ 110 mph. 273 = 5.11, 318 = 4.38, 360 = 3.87, 440 = 3.18, 3.23-3.55 are consider decent compromise gears but that's really only for larger engines since they would be closer to ideal for them anyways than would be for smaller engines.

Why one of my Signature's is "If your willing to gear it build it if not build a larger displacement, Or take solace in your compromises."
 
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What gearing would you do on this 318 since it will be street/freeway occasionally
 
A 3.73 with a 26'' tall tire will give it get up and go. We have built several cars with 3.73 for a good compromise .
Want more highway go with a 27'' or 28'' tire to reduce cruising rpm.
 
Okay thank you I’ll stick with the 3.73 gears then I’m sure it’ll be okay
 
Should I do 1.800 comp height pistons and then deck the block so it’s true which these pistons are around 9.7 comp with 64cc heads. The heads I have are 65cc closed chamber and then I’ll use .039 fel pro gasket for its reliability
 
Joey N said:
Should I do 1.800 comp height pistons and then deck the block so it’s true which these pistons are around 9.7 comp with 64cc heads. The heads I have are 65cc closed chamber and then I’ll use .039 fel pro gasket for its reliability
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Id say yes. It looks like that would up the compression. What casting are the heads? 273-318 or 340-360? the intake runners etc. are different between the two families of head but its all about cfm if you can get the flow its all good.
 
I’m using aluminum heads the ones that were on it are open chamber 675 heads surprisingly the engine was cranking 170psi per chamber
 
Dartswinger70 said:
People may hate this but, my other car is an 86 Mustang GT 5.0 with 2.73s and 5 speed. I can take that car anywhere highway trips cruises etc. That is just a plain old light weight 200 horse daily driver type fuel injected v8 car.
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I love Fox bodies.
 
Joey N said:
I’m using aluminum heads the ones that were on it are open chamber 675 heads surprisingly the engine was cranking 170psi per chamber
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make sense the old LA 340 X and J heads were open chambers used piston domes for compression. It sounds like you have good flowing heads with the big runners. so great! Yeah you get the pistons to 0 deck height with closed chamber it should be good compression wise. Pretty hot actually
 
Current pistons are 1.720 or 1.740 comp height so no good that’s why I’m going new
 
Joey N said:
What gearing would you do on this 318 since it will be street/freeway occasionally
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Whatever gear/stall you choose, build around that, too many build to some vague power but cripple it with gear and stall selection. Stall speed is more important than gearing.

To me you want to build as much 3500-5500 rpm power as you can without overly compromising to much of the 1500-3500 rpm drivability (depending on personal taste), also wouldn't hurt if it pulled to 6000+ rpm, so basically looking to make peak hp around 5000-5500 rpm and peak torque around 3500-4500 rpm. If looking a decent Hot street engine, if looking to make more power than that got to go with more displacement and or more rpm (peak hp 5500-6500+ rpm) becoming more of street strip engine needing/necessary deeper gears and stall.

Eg..

323 making 1.18 lbs-ft per cid = peak torque of 381 lbs-ft around 3500-4500 rpm, if peak torque was 381 lbs-ft @ 4000 rpms would also be 290 hp @ 4000 rpm.

Say peak hp is at 5252 rpm basically half way between 5000-5500 rpm, since torque and hp is the same at that rpm, torque is generally around 87-93% of peak torque or so at peak hp.
So say 90% x 381 hp = 343 hp @ 5252 rpm. If that's not enough either needed more rpm and or higher efficiency which ain't exactly easy to do compared to more rpm or generally what people do is more cid.
 
Joey N said:
Should I do 1.800 comp height pistons and then deck the block so it’s true which these pistons are around 9.7 comp with 64cc heads. The heads I have are 65cc closed chamber and then I’ll use .039 fel pro gasket for its reliability
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I'd go with that cr that works with cam and gasoline choice and the piston has to make that cr with whatever head your gonna run, and maybe keeping in mind possible future upgrades.
 
Joey N said:
I don’t even know where my nearest track is barona? junkyardhero probably knows but I’m looking to have a better sounding and out preform my brothers 350 nova we don’t know what’s done to the engine but it’s quick and sounds pretty good but I really don’t know what’s been done to it TH400 shift kit but at some point I’d chassis Dino to see what I’m making and at some point take it to the strip wherever that is
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yeah barona is i think the only thing left in socal now.

like @318willrun said "don't get sucked into the horsepower trap" there is also the "don't get sucked into the 'sounds good' or 'want it to have that chop' trap"

just because a car sounds good don't mean squat. i've built cars that sound damn near stock and will knock your hat in the creek.
 
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Joey N said:
What gearing would you do on this 318 since it will be street/freeway occasionally
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For the street and Hwy. I don’t like to exceed 3.55’s.
A 26” tire for reference.
It’ll turn 3K plus like this. If there is much of a performance cam in the engine, it starts to get thirsty.
This is hot rod street driver stuff for me.

Normally for a driver that will see the Hwy and cruise at 70-75, I’ll use the 2.94 and numerically lower gears and keep the cam a step or two above stock at most. This is still a good mileage maker and a sweet driver.

When I stick in 4.10 & more, the interstates are out of the question. Even more so here in armories where you get run over and given the big stuff middle finger below 70 in the right lane. I’m sure there are choice words involved that I can’t hear.
junkyardhero said:
yeah barona is the i think the only thing left in socal now.

like @318willrun said "don't get sucked into the horsepower trap" there is also the "don't get sucked into the 'sounds good' or 'want it to have that chop' trap"

just because a car sounds good don't mean squat. i've built cars that sound damn near stock and will knock your hat in the creek.
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Hell yea buddy!
 
i agree with the sentiments on gearing. if you're in town mostly the 3.73's are gonna be nice but if you're planning on hitting the super slab be ready to hang that bish at 3500 because otherwise you're gonna be slow poking it in the RH lane.

3.55's is what i would consider the upper limit for a touring car and even then with special consideration on tire height and the carb selection so i don't go broke feeding it.
 
junkyardhero said:
i agree with the sentiments on gearing. if you're in town mostly the 3.73's are gonna be nice but if you're planning on hitting the super slab be ready to hang that bish at 3500 because otherwise you're gonna be slow poking it in the RH lane.

3.55's is what i would consider the upper limit for a touring car and even then with special consideration on tire height and the carb selection so i don't go broke feeding it.
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This is where a OD transmission is great to make use of.
 
People that want to run highway gears and no overdrive but want to make 400+ hp probably should be looking into running large low rpm 0.8 - 1 hp per cid engines.
 
I had a 383 for my duster but decided not to do it because the 318 is so much less weight on the front end and so I would rather it handle better and that 383 was a pain in the *** to roll around my dirt back yard on a cherry picker with steel wheels :rofl:
 
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