360 mopar wondering estimated HP??

[chasonmarose]

I have a 360 In my 74 d 100

My build is as followed

.040 bore
.040 crank and rods

3.58 stroke
4.040 bored block
Xe275hl comp cam .525/.525 275/287
Kb 107 pistons
Stock rods
Stock crank
Holley strip dominator high rise intake
Holley street avenger 670cfm
Stock heads 2.02 Intake 1.60 exhaust
Flow tech long tube headers
True duals into flow master super 44s
Ignition is a hei Chevy style 50000 volt it supposedly does
Timing set at 35 degrees with mechanical once vacuum advance is hooked up about 60 degrees around 3200rpm

What compression and hp do I have??

Oh and my heads I don't see a j or an X on them no casting number under valve cover on intake runner either. Has the half moon heat exchanger on the heads tho. No idea what cc they are

 

[DartVadar]

Im using the same pistons in my 360 but with 63cc eddy heads and a .39 head gasket, I have around 10.5:1.

I would say a bit over 9:1, its hard to give an accurate answer because you don't know the chamber size, or head gasket thickness. But I think 360 heads are 72cc...not 100% sure about that though.

I'm using a bit of a smaller cam with my combo and I'm making a bit over 400hp, I would say you have mid 300s. Hard to say though, too many unknowns...

 

[fratzog lover]

Do you have the large DUI style HEI distributor? What body are you putting this engine in? You may have a clearance issue. The Tri power distributor will fit however.

 

[chasonmarose]

When I looked back into the books the cc size for my heads is around 65 cc. The head gasket thickeness is .39 like urs. And the distributor just fits with about 3/4 inch clearance from the firewall in my truck! The truck only has 2.73 ratio in the rear end but it goes like stink. Just wasn't to sure on the compression as it burns 87 octane pretty good

 

[rumblefish360]

The comp. Ratio is determined by a lot more info than you give plus the cylinder head cc amount you think you have is probably VERY inaccurate because you read it in a book. That book is more likely giving you the min. cc amount that the head can have rather than the actual amount which would require you to cc the head. All the things that are needed to be know are;

The pistons deck height & the amount of cc's the piston has for the valve reliefs or dome cc amount. The KB-107's have a (IIRC) 5cc valve relief.
Head gasket thickness & bore size
Cylinder head cc amount
Bore and stroke

To help calculate the HP level, the cams duration at .050 should be given because there is a lot of free play in the advertised duration.
The header tube size should be given though most know your header is @ 1-5/8 in the typical 1 size fits all header design. Also the exhaust tube size. 2-1/4? 2-1/2? 3 inch pipe size?

Just incase you didn't know, a simple FYI, the cylinder head casting numbers are also located I between the middle two runners under the head. With the intake removed, you can use a mirror to see them. Otherwise, the head has to come off.
The have moon shape in the cylinder head is supposed to be there. No worries.

The only thing in an day about your build is that all your missing is cylinder head flow. Once you port them puppies out, it's gonna wake up!
Minus the ported heads, nice combo for power and fun. It should be real enjoyable.

 

[chasonmarose]

My head cc are 65 intake runner 179 exhaust 67
.40 bore and 3.58 stroke. Gasket size is .49
When I used a compression Calculator brought me to about 10.75 to 1. Just wondering a rough horsepower estimate

 

[RustyRatRod]

Somewhere tween 1 and 500.

 

[Bakerlite]

If you flick RustyRatRod a few $$$$ he can run up some numbers on an engine sim for you.

 

[autoxcuda]

My head cc are 65 intake runner 179 exhaust 67
.40 bore and 3.58 stroke. Gasket size is .49
When I used a compression Calculator brought me to about 10.75 to 1. Just wondering a rough horsepower estimate

You just cc'd your heads?

If not, get the casting numbers off the head and there's a typical measured CC for stock heads. It's a guess because you don' know how much your head have been surface cut or milled. But it will put you in the ballpark.

IMHO, that cam, strip dominator single plane, and 670 cfm vacuum secondary carb seem like a slight mismatch. I'm thinking more carb or less (dual plane) intake.

 

[autoxcuda]

The comp. Ratio is determined by a lot more info than you give plus the cylinder head cc amount you think you have is probably VERY inaccurate because you read it in a book. That book is more likely giving you the min. cc amount that the head can have rather than the actual amount which would require you to cc the head. All the things that are needed to be know are;

The pistons deck height & the amount of cc's the piston has for the valve reliefs or dome cc amount. The KB-107's have a (IIRC) 5cc valve relief.
Head gasket thickness & bore size
Cylinder head cc amount
Bore and stroke

To help calculate the HP level, the cams duration at .050 should be given because there is a lot of free play in the advertised duration.
The header tube size should be given though most know your header is @ 1-5/8 in the typical 1 size fits all header design. Also the exhaust tube size. 2-1/4? 2-1/2? 3 inch pipe size?

Just incase you didn't know, a simple FYI, the cylinder head casting numbers are also located I between the middle two runners under the head. With the intake removed, you can use a mirror to see them. Otherwise, the head has to come off.
The have moon shape in the cylinder head is supposed to be there. No worries.

The only thing in an day about your build is that all your missing is cylinder head flow. Once you port them puppies out, it's gonna wake up!
Minus the ported heads, nice combo for power and fun. It should be real enjoyable.

Exhaust Valve Lift (in.)

0.525

Intake Valve Lift (in.)

0.525

Exh. Duration @ .050 in. (Deg)

237

Int. Duration @ .050 in. (Deg)

231

Int. Duration Advertised (Deg)

275

Exh. Duration Advertised (Deg)

287

Lobe Seperation (Deg): 110

 

[RustyRatRod]

If you flick RustyRatRod a few $$$$ he can run up some numbers on an engine sim for you.

Now why would he want to do a fool thing like that? Then he'd have something concrete to go on instead of all the guesswork. It just makes too much sense.