Brainstorming an Idea, whats your 2 cents

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Brambles

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O.K. here's the history. I had an engine built a couple years ago for my 1986 Dodge ram 4x4. I built it with the intention of running it in a car later in life. This is what I had done.

1978 360 block
Stock crank ground .010/.010
Rods resized and small end narrowed to 1" for pistons
ARP rod bolts
Windage tray
Stock volume oil pump
Keith black KB362 pistons ( for magnum heads) "0" deck height
Everything balanced with dampner and 360 truck flywheel

Heads
1996 360 magnum heads Ported and combustion chambers polished
Valve job
Bronze valve guides
Stock valves
Machined the valve spring seat and guide
Can't remember what valve springs but they were matched to the cam.

MP M1 dual plane magnum 4 bbl intake and edelbrock 600 cfm carb
Flowtech ceramic headers and dual 2 1/4 flowmasters.
I have run 2 cams #1 Engle cam 216/216 @.050 .488 lift in/ex w 1.6 rockers
#2 Comp cam XE250H can't remember the specs but thats what's in there now, for more torque and mileage


Now I'm thinking of putting in a 408 stroker crank so I'll have to machine about .21 off the top of the pistons to stay at "0" deck height, they are dished pistons so there should be plenty of room to mill. Plus the extra compression would be nice when I put in the bigger cam for the car.
I'll have to re-balance everything I'm sure.

Can I use this truck flywheel with my A-833 4 spd tranny or are the car flywheels different from the truck flywheels? The transmission is a 4 spd with granny low 1st gear made by New process as well I think NP 435.

What cam do you think will make 450 hp in the 408?
What cam do you think will make 450 hp in the 360?
 
Before I even think of a cam, you'll need a better intake and larger exhaust pipes.
Then for the 408, I would for surley dump the widage tray and get a deep pan and tray set up from Mildon or ....And large tube headers.

All parts from car or truck are the same basicly, do not worry. Theres just a question of balance.

Cam recomendations are a lot like what color socks should I wear with my hair style?
 
Oh yeah, I forgot to mention when I put the engine in a car I'm going to install a single plane intake and will run dual 2.5 or 3" exhaust. I'll probably put bigger valves in as well but not sure??
 
Personally I think that motor is all wrong for a 4" crank. It will make tons of torque but be out of breath at a low rpm, probably 5000rpms or so. The 4" crank will want a bigger intake, cam and head work. I would stick with the 3.58" stroke, add a bigger cam like a Comp cams 280H or XE274H, a Perf RPM intake and a 750 carb.
 
Probably not the response you'd want, but, I'd start with a clean slate.
Sell the engine and use the money towards the stroker. Or use that motor untill you have the stroker ready. No good can come of milling almost .250 off the pistons. KB's are too thin for that action. You'd be much happier if using the right pistons for the combo. You haven't even considered valve/piston clearance.
 
AdamR said:
Personally I think that motor is all wrong for a 4" crank. It will make tons of torque but be out of breath at a low rpm, probably 5000rpms or so. The 4" crank will want a bigger intake, cam and head work. I would stick with the 3.58" stroke, add a bigger cam like a Comp cams 280H or XE274H, a Perf RPM intake and a 750 carb.
Click to expand...


I have a feeling I haven't expressed what my ideas are very well.

I am going to change my cam
I am going to change my intake and carb
And I might do some more head work.

I have a email into Kieth black to find out if its safe to mill the piston by this amount.

Thanks

Brambles
 
I would not mill those pistons, there are sets specifically designed for stroker applications which wont require any machining.

I dont think the flywheel from a truck motor is the same size, I believe they are larger, at least in the old days they were. If your motor is externally balanced the flywheel wont work with the stroker crank anyway. It would need rebalancing to match the crank rod pistons etc.

I'd take the motor as is and put in a healthier cam matched for your intended application - car, axle ratio, trans type, etc., and use it.

Meanwhile I'd collect a good core block and the pieces to build a stroker from scratch, once done, sell the 360 as a running piece. All you'd be loosing is the cost of machining the block for the new motor, because you'd want to go thru the old motor anyway.. at least I would. You might actually come out better money wise selling the other engine as a whole running piece, depending on what you get for it.

My .02....good luck deciding !
 
I would replace the pistosn with forged if a sonic check shows it safe to go to .040 over, or if the bores are in good shape and with just re-honing you can keep the piston to wall clearances close. I dont use factory rods with 4" cranks. The heads will limimt your power by a bit. Magnums have a purpose, but a small block over 400" just isnt it. To be honest, you have a nice solid combo...Why not just add a decent cam and headers to it, maybe a single plane, and run it that way? The heads will make 450hp or so maxxed on a 360. They will make 450 on a 408 or 410 too...But they will be out of breath early and you could make a bit more with better heads.
 
The other reason I am considering a stroker crank is because I might have to tear the engine down for a low oil pressure problem being discussed on another thread right now. Plus I found out that the guy that built my motor had stripped the first 1/2 inch of thread out of the snout of the crank. I don't like this at all and would prefer to change the crank, SOOOOOO why not change to a stroker crank if it turned out to be a basic swap????


Yeah, The guy who built my motor was a complete goof and I now regret getting him to build it, more problems that I care to discuss...Lesson learned the hard way.
 
Sorry to hear your problems with the rebuild on that engine. I can understrand your frustration and desire to fix the basic problem of a crappy rebuild and low oil pressure. But I dont think it will be a basic swap changing to a 4.00" crank and milling the pistons.(providing KB says it can be done), Id research it more before spending more money, could end up being a very expensive engine and still not correct.
Muscle Motors recommended a Milodon 7 quart pan/pick up, and high volume oil pump for my 450 hp 408 build. The stroker route will require better heads and bigger carb to be effective, 1 & 5/8" headers were a bottle neck on mine, "had" to spend more $ for 1 3/4 " Hookers (big improvement). The stroker thing is cool, but my 350 hp 360 in my other Duster is cheaper to build / cheaper to operate and is great for the street .
 
I heard back from Keith Black.
They said its safe to mill to .160 from the top ring. I guess I'll have to wait and see how much meat is there to start with when I tear the engine down, unless someone has a KB362 piston handy for a measurement???

Brambles
 
The pistons will need to be .420" shorter to be at the same spot as the ones you have now. You cannot mill more than .160. So even if your pistons are in .040 down, you are still too tall by just shy of 1/4". You either need to replace them, or replcae your carnk. FYI I have a 360 that needs a crank kit. I priced it at $175 for a crank and bearings with exchange. Your KBs are lighter than factory cast, so if yo simply swapped cranks, you would be overbalanced. That's not what I love to have, but it's better than being underbalanced. Plus, you could have the new crank spun and weight matched to the old crank. Then it's a drop in deal. The whole mess might cost $400. Add a light hone and new rings, and you're done for $600 or so...
 
moper said:
The pistons will need to be .420" shorter to be at the same spot as the ones you have now. You cannot mill more than .160. So even if your pistons are in .040 down, you are still too tall by just shy of 1/4". You either need to replace them, or replcae your carnk. FYI I have a 360 that needs a crank kit. I priced it at $175 for a crank and bearings with exchange. Your KBs are lighter than factory cast, so if yo simply swapped cranks, you would be overbalanced. That's not what I love to have, but it's better than being underbalanced. Plus, you could have the new crank spun and weight matched to the old crank. Then it's a drop in deal. The whole mess might cost $400. Add a light hone and new rings, and you're done for $600 or so...
Click to expand...



Sounds like thats the best option Moper. I'm going to drop the Pan next time I have a chance and see if there is indeed silicone plugging up the pickup.
Best to check out the simple solutions first.
 
Brambles said:
O.K. here's the history. I had an engine built a couple years ago for my 1986 Dodge ram 4x4. I built it with the intention of running it in a car later in life. This is what I had done.

1978 360 block
Stock crank ground .010/.010
Rods resized and small end narrowed to 1" for pistons
ARP rod bolts
Windage tray
Stock volume oil pump
Keith black KB362 pistons ( for magnum heads) "0" deck height
Everything balanced with dampner and 360 truck flywheel

Heads
1996 360 magnum heads Ported and combustion chambers polished
Valve job
Bronze valve guides
Stock valves
Machined the valve spring seat and guide
Can't remember what valve springs but they were matched to the cam.

MP M1 dual plane magnum 4 bbl intake and edelbrock 600 cfm carb
Flowtech ceramic headers and dual 2 1/4 flowmasters.
I have run 2 cams #1 Engle cam 216/216 @.050 .488 lift in/ex w 1.6 rockers
#2 Comp cam XE250H can't remember the specs but thats what's in there now, for more torque and mileage


Now I'm thinking of putting in a 408 stroker crank so I'll have to machine about .21 off the top of the pistons to stay at "0" deck height, they are dished pistons so there should be plenty of room to mill. Plus the extra compression would be nice when I put in the bigger cam for the car.
I'll have to re-balance everything I'm sure.

Can I use this truck flywheel with my A-833 4 spd tranny or are the car flywheels different from the truck flywheels? The transmission is a 4 spd with granny low 1st gear made by New process as well I think NP 435.

What cam do you think will make 450 hp in the 408?
What cam do you think will make 450 hp in the 360?
Click to expand...

I had a hotter cam (218/228 @ .544) and I got a magnum 360 (9.1:1 comp) with Pro-ported heads (Koffels Place) and an M1 with Aluminum Roller Rockers that put down 301HP and 330TQ to the rear wheels. So, no I dont think you have enough cam to make 400hp. With a lot more cam, you might be able to hit 450, but you will need at least 10:1 comp ratio.
 
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