390 stroker build

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CUDACOX

CUDACOX

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O.K. I'm collecting parts for my future stroker build.Has anybody used a MP purple shaft 484/284 in a stroker build? Also what intake would work best? Not going all out with this build,just the basics. Thanks in advance!
 
Hi Craig. My 2 cents........That cam would be mild with a 4" stroke, an absolute torque monster, but mild. If you decided to go that way, my only concern might be where your compression ends up? You may need more cam to bleed off some in certain situations. As for intake, the RPM/RPM Airgap will probably be the overwhelming choice here. Good Luck, that's gonna be a blast to drive when it's done. :thumrigh:
 
OldmanRick said:
Hi Craig. My 2 cents........That cam would be mild with a 4" stroke, an absolute torque monster, but mild. If you decided to go that way, my only concern might be where your compression ends up? You may need more cam to bleed off some in certain situations. As for intake, the RPM/RPM Airgap will probably be the overwhelming choice here. Good Luck, that's gonna be a blast to drive when it's done. :thumrigh:
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Thank You for the kind reply. I want a torque monster,don't need a screamer.I'm intend on using maybe X or J heads with a decent port/valve job,and stock 68-70 340 manifolds. All I'm looking for is a thrill when stomping it to the floor and maybe high 12's? in the 1320. 3:55 rear and built 727 with 2800 stall.
 
CRAIG COX said:
Thank You for the kind reply. I want a torque monster,don't need a screamer.I'm intend on using maybe X or J heads with a decent port/valve job,and stock 68-70 340 manifolds. All I'm looking for is a thrill when stomping it to the floor and maybe high 12's? in the 1320. 3:55 rear and built 727 with 2800 stall.
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I'll nose around some specs just for some fun and see what's out there. I assume you'll use a KB hyper piston that's readily available and your head cc will be in the 70/72 range with the "J"s and 66/68 range with "X"s. In the end a dynamic comp. ratio in the 8.0/8.25 range will allow you to not worry about premium pump gas quality. Also, with the manifolds, a split duration cam will be a must to help get the exhaust out.....Just my opinions, so others don't chop my head off........lol. Later, Rick
 
OldmanRick said:
I'll nose around some specs just for some fun and see what's out there. I assume you'll use a KB hyper piston that's readily available and your head cc will be in the 70/72 range with the "J"s and 66/68 range with "X"s. In the end a dynamic comp. ratio in the 8.0/8.25 range will allow you to not worry about premium pump gas quality. Also, with the manifolds, a split duration cam will be a must to help get the exhaust out.....Just my opinions, so others don't chop my head off........lol. Later, Rick
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Wow, I was thing maybe 9.0-9.5 comp. So you think the 484/284 cam won't do the trick?
 
CRAIG COX said:
Wow, I was thing maybe 9.0-9.5 comp. So you think the 484/284 cam won't do the trick?
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I was talking dynamic comp. not static :D. Dynamic takes into account cam timing also. About the max dynamic you can run on pump gas is around 8.75 to 1 and you have to be really careful with ignition timing at that. I'm sure you will want to be in the 9 to 10 range for static compression.

Also, i was just looking at pistons and there not as widely available as the 340/360 based strokers. I did see the KB/Icon forged, but? Have you talked to anyone, shop, about it yet? Or have you looked into rotating assemblies? Just curious what you'll end up using.
 
OldmanRick said:
I was talking dynamic comp. not static :D. Dynamic takes into account cam timing also. About the max dynamic you can run on pump gas is around 8.75 to 1 and you have to be really careful with ignition timing at that. I'm sure you will want to be in the 9 to 10 range for static compression.

Also, i was just looking at pistons and there not as widely available as the 340/360 based strokers. I did see the KB/Icon forged, but? Have you talked to anyone, shop, about it yet? Or have you looked into rotating assemblies? Just curious what you'll end up using.
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Most likely will buy a rotating assembly.I have a builder I've known for years.Old school hobby builder/drag racer.. Only Mopar of course! lol..
 
CRAIG COX said:
Most likely will buy a rotating assembly.I have a builder I've known for years.Old school hobby builder/drag racer.. Only Mopar of course! lol..
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That's nice to have someone you can trust.

I've been running some random numbers, but just too many unknowns at this point for a cam choice. I will say that the cam you spoke of would not be completely out of the question if all the stars align, although i'm sure there will be better choices to use with the stock manifolds.
 
Sorry, didn't mean to leave you hangin' in post #7. What i should say is, when the piston choice, deck height and head choice (for cc" purposes) is known, then some caculations can be made that will help with cam choice.

Also, i didn't mention it, but the 3.55 gear should be perfect for what you're doing.
 
Craig, I Wish I could remember the spec's on the cam I had in my 390 stroker,but I can't I do remember I had one custom ground for it. I also went with 3.55's you can even get away with 3.23's if you wanted. Their is so much torque. I also used the Magnum heads on mine. I think the J head would be fine too. Their's alot of good intake's I would use a single plane. Good Luck and keep us posted!
 
Do you already have the 284/484? If so, run with it. If you're buying new, there are so many more modern choices out there. On the plus side, the old purple shaft cams usually run a fair bit of overlap, which will help bleed off some cylinder pressure if your compression ends up a little on the higher side. Have fun, sounds like a fun build!
 
jd340 said:
Do you already have the 284/484? If so, run with it. If you're buying new, there are so many more modern choices out there. On the plus side, the old purple shaft cams usually run a fair bit of overlap, which will help bleed off some cylinder pressure if your compression ends up a little on the higher side. Have fun, sounds like a fun build!
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Yes, I already have this new in box,cam and lifter set.
 
R4Sedan said:
Craig, I Wish I could remember the spec's on the cam I had in my 390 stroker,but I can't I do remember I had one custom ground for it. I also went with 3.55's you can even get away with 3.23's if you wanted. Their is so much torque. I also used the Magnum heads on mine. I think the J head would be fine too. Their's alot of good intake's I would use a single plane. Good Luck and keep us posted!
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Please tell more of your build.
 
Craig, I wish I had the paperwork on that engine. My friend had originally started building the stroker motor back in '06 or '07 for his '70 Dart. At that time I was building a '70 Challenger. While all this was happening my friend had a massive heart attack and died. His brother sold me the stroker motor (I really didn't know much about them) I knew my friend had bought the kit, pistons,heads so forth from
Hughes. I explained to them what happened and they e-mailed me the invoices showing everything he had purchased. It was about 6300-6800 I can't remember know.But, the heads were Magnums, slightly ported, Hughes Stroker kit, 8qrt oil pan, eagle rods, I can't remember what, pistons. It was a Hughes cam too, but the guy that built it wanted more duration that's why we had a different one made.
I don't have any of the P/W because when things got bad a couple years ago I had to sell the car. I sure do Miss that car. I think when I get the Valiant done I'll start another project and build a 390 stroker. Oh and it had a 750 Demon carb. I'll look for some pic's and post.
 
R4Sedan said:
Craig, I wish I had the paperwork on that engine. My friend had originally started building the stroker motor back in '06 or '07 for his '70 Dart. At that time I was building a '70 Challenger. While all this was happening my friend had a massive heart attack and died. His brother sold me the stroker motor (I really didn't know much about them) I knew my friend had bought the kit, pistons,heads so forth from
Hughes. I explained to them what happened and they e-mailed me the invoices showing everything he had purchased. It was about 6300-6800 I can't remember know.But, the heads were Magnums, slightly ported, Hughes Stroker kit, 8qrt oil pan, eagle rods, I can't remember what, pistons. It was a Hughes cam too, but the guy that built it wanted more duration that's why we had a different one made.
I don't have any of the P/W because when things got bad a couple years ago I had to sell the car. I sure do Miss that car. I think when I get the Valiant done I'll start another project and build a 390 stroker. Oh and it had a 750 Demon carb. I'll look for some pic's and post.
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That would be great! Thanks.
 
Craig, here's one crappy picture all my others were on my other computer that crashed, so I will have to scan some.
 

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CUDACOX said:
Anybody else? Please share in your builds..:prayer:
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Okay, probably not too relevant as I threw a little more $$$ at it.
Mine has the Scat cast crank, I-beams and Icon forged flat tops, clevite bearings and total seal rings, internally balanced with NO mallory metal needed. A stock oil pump with the pick up relocated to the oil pump cover to suit a fabricated aluminum pan from Charlie's oil pans. Ported RHS heads with 2.02"/1.62" valves, and 67cc chambers from Brian at IMM Engines. Billet hydraulic roller with [email protected]" and .402" lobe lift on a 112LSA also from IMM), with Comp Magnum shaft rockers and custom length Manton 11/32" pushrods. Ported Eddy RPM intake with a TMP 1000HP carb. MSD Pro Billet , Mallory Hyfire VI ignition box, ATI Super Damper and a CSR electric water pump.
Modified Schoenfeld 1 3/4" headers.
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CUDACOX said:
Looks great! Let us know when you install it and when you have a go at it!
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Will do. At 2300lbs with aluminum seats and no carpets, radio etc. its more strip than street but its got a title, mufflers and treads so I'll do as much street driving as I dare.
 
Some basics - If you are running factory heads then you will still want to run a dished piston. That will give you a static compression anywhere from 9-10:1. Factory heads are terrible in terms of tendency to detonate so you want to be very careful about the cam choice. IMO, the 284/484 is a mistake. If you have to stick with the MP line up the 509 is a better choice, although honestly I wouldn't run any of the MP camshafts because there are MUCH better out there. If you go modern design, look for something in the 235° @ .050 to 245° @ .050 and you should be fine. Anything less (smaller) and you may have issues with pinging.
 
Hey Craig,in my stroked 340(372c.i)I run Keith Black 107 pistons with X heads(compr is 10.5-1)my cam is a Comp Cam XE284H #20-225-4 Hyd. Flat Tappet 240/246 507/510 @110* rockers are Pro Magnums. I run a Scat Steel crank(3.58)Engine was built and dynoed by Beatty&Woods 452hp@5800rpm 440ftlbs@4400rpm.
Good luck with the build.:D
 
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