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Looking for 360 Build Ideas

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Sonic Silver View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sonic Silver Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 12:41pm
Originally posted by Trader Trader wrote:

Your likely looking in the wrong place for HP.
1 point of SCR is approximately 3% to 4% HP gain at 100% VE.
HP = 0.257 x CFM x number of cylinders, again approximately, at 100% VE.
You will get more HP with VE then you can gain with SCR.
Our older engines are typically 80% stock, 85%+ modified and up to 110% VE on a fully ported built race engine.
HP is in head flow. Thermal efficiency is in SCR. The best combine these into a working package. 
As Rick did with the Jeep build. I could take the time to calculate that engines head flow if I knew the camshaft used, but can tell you now it's heads were ported to no less then 250 CFM. 
I did say general guidelines for SCR & DCR.
 
Rick said that he used the small Summit 8600 with 214/224 duration at .050 and from memory .473/.497 lift. I could be off a bit on intake lift.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote CamJam Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 1:12pm
Originally posted by Trader Trader wrote:

Your likely looking in the wrong place for HP.
1 point of SCR is approximately 3% to 4% HP gain at 100% VE.
HP = 0.257 x CFM x number of cylinders, again approximately, at 100% VE.
You will get more HP with VE then you can gain with SCR.
Our older engines are typically 80% stock, 85%+ modified and up to 110% VE on a fully ported built race engine.
HP is in head flow. Thermal efficiency is in SCR. The best combine these into a working package. 
As Rick did with the Jeep build. I could take the time to calculate that engines head flow if I knew the camshaft used, but can tell you now it's heads were ported to no less then 250 CFM. 
I did say general guidelines for SCR & DCR.
 

Your point is well taken.  Just to see if though it makes sense to use these 343 pistons, can anyone tell me what the dish volume is for the factory 343 4V and 2V pistons?  I'm guessing 343 2V piston would be a better choice for me, but that's not what I have so that plan might not be workable.

Without getting into boost, from what I'm hearing it seems like porting the stock heads (or maybe the Eddy heads?) along with a decent cam, 650 cfm carb and intake might make as much sense as anything.


'73 Javelin 360 (current project)
'72 Baja Bronze Javelin SST
'69 Big Bad Orange AMX (2018 Teague Heritage Award) SOLD

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SC397 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SC397 Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 3:19pm
"Just looking for a nice performance driver, but reliable enough to drive all day at 75-80 mph in case I ever choose to drive it across the country."

Why do you think you need 400 HP?
You only need about 150 hp to burn up tires and haul lawn chairs.
One of the best combinations for a cheap, reliable 300+ hp low compression 360 engine is a simple one.
Comp 268H cam
Performance valve grind.
Pick your flavor of aftermarket intake manifold.
650 to 750 Holley.
Headers or Free Flow manifolds.
2 1/4" - 2 1/2" exhaust. 

Or, you could jack the compression up and burn E85.



Edited by SC397 - Aug/07/2022 at 3:21pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sonic Silver Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 3:24pm
Originally posted by SC397 SC397 wrote:

Why do you think you need 400 HP?
You only need about 150 hp to burn up tires and haul lawn chairs.
One of the best combinations for a cheap, reliable 300+ hp low compression 360 engine is a simple one.
Comp 268H cam
Performance valve grind.
Pick your flavor of aftermarket intake manifold.
650 to 750 Holley.
Headers or Free Flow manifolds.
2 1/4" - 2 1/2" exhaust. 

Or, you could jack the compression up and burn E85.

You beat me to it. I was going to say approximately the same, except was going to suggest a cam in the 2 teens duration at .050 and I have done just as well with 600 cfm carbs on 360's. Close enough. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SC397 Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 3:29pm
LOL!
Ok, a 600 cfm with a Performer intake and 650+ cfm with a Air Gap or Torker.
Or just go with EFI.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sonic Silver Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 3:35pm
Originally posted by SC397 SC397 wrote:

LOL!
Ok, a 600 cfm with a Performer intake and 650+ cfm with a Air Gap or Torker.
Or just go with EFI.
Let me put it this way. A 600 and a 750 cfm carburetor were 1 horsepower apart on my 360 with an Air Gap at 5500rpm, so my guess is that anything in that range would suffice. There were up to 10 ft/lbs difference at different rpm's, but the averages and peak were the same.

Edited by Sonic Silver - Aug/07/2022 at 3:37pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote WesternRed Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 5:17pm
Couple of things, with the Eddy heads you can run a bit more compression.

343 2V pistons would probably be a good thing, but they are not readily available, the valve pockets on the 4V pistons run to around 5cc.

I've found the deck clearance to be around 0.020" rather than the factory spec 0.012".

Compression in itself might not add a lot of power, but it usually allows you to run a bigger cam to get more air in and that's where the power comes from. Nicely ported heads can do the same thing with a milder cam it seems.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote CamJam Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 5:43pm
Originally posted by SC397 SC397 wrote:

"Just looking for a nice performance driver, but reliable enough to drive all day at 75-80 mph in case I ever choose to drive it across the country."

Why do you think you need 400 HP?
You only need about 150 hp to burn up tires and haul lawn chairs.
One of the best combinations for a cheap, reliable 300+ hp low compression 360 engine is a simple one.
Comp 268H cam
Performance valve grind.
Pick your flavor of aftermarket intake manifold.
650 to 750 Holley.
Headers or Free Flow manifolds.
2 1/4" - 2 1/2" exhaust. 

Or, you could jack the compression up and burn E85.


Ever notice that everybody wants to race a muscle car?  I just don't like getting blown away by Kias and Hyundais.   LOL

I have free flow manifolds and just put a 2-1/4" dual exhaust on the car, so we're part of the way there.

'73 Javelin 360 (current project)
'72 Baja Bronze Javelin SST
'69 Big Bad Orange AMX (2018 Teague Heritage Award) SOLD

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Post Options Post Options   Thanks (0) Thanks(0)   Quote CamJam Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 5:51pm
Ok, how about this?

Eddy heads
Performer manifold
Holley or Summit 650 carb
Comp 268 Cam
Pistons TBD, but something to give me about a 9.5-10 CR

Any guess as to hp on that package?

'73 Javelin 360 (current project)
'72 Baja Bronze Javelin SST
'69 Big Bad Orange AMX (2018 Teague Heritage Award) SOLD

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Post Options Post Options   Thanks (1) Thanks(1)   Quote amxdreamer Quote  Post ReplyReply Direct Link To This Post Posted: Aug/07/2022 at 5:56pm
Cam, Rick is right on the money. The whole I have 400hp or I have 500hp etc is just for bragging rights at the DQ. 250-300 HONEST HP is enough for a fun cruiser. Most people never drive them to the max or don't have the skill to drive them to the max anyways. There are so many bogus HP claims by ego's in the hobby, don't fall to that mentality. My AMX is plenty quick with a basic build and is still fun to drive and bark gears. Throw a good set of gears in the back and an overdrive and it will do everything you want. 

The 360 in my "cruiser" is basic also but with a Torker and highway gears. Definitely not a great combo BUT it's still fun....then again not many people try to race me. lol Took it for a decent drive through the pass yesterday and managed 15mpg which isn't too bad for a big car with a lot of wind resistance!

Tony
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