318 to 390 stroker

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Icon shows Magnum OE Deck Height: 9.578 (some say Magnum is 9.588")
not LA- Non Magnum is 9.600" or 9.59 blueprinted
I do not know what NHrA minimum is but that is often quoted as stock but is much shortr
what yours going to be
 
Seen that number before in that catalog, wyrm.... as best I have even been able to find, it is a mistake. They show the same 9.578" in the KB line for 318's. If you work the numbers for their advertised static CR's, you have to use that 9.578" number to get there.

AFAIK....Magnum should be nominally 9.585"...LA at 9.600". If this number IS correct (which I doubt), then I got some 318 CR corrections to make by about 1/3 point!
 
diamond and race-tec can dish their flat tops to most whatever dish you need
I would think others could too
 
We got the rotating assembly back finally. Ended up right at 10:1 compression. DCR calculates out to 7.9:1 with the comp xe274 cam that the builder recommended. Should be quite the runner all said and done. We have a tc coming from ultimate converter with a stall in the 2800 to 3200 range. Do any of you have experience running a holley avenger carb? Thinking well slap on a 670 avenger.
 
670 avenger is a great carb. Have 2 of them. One for my 357 sbc and my 318. Might be a bit small for a 390 though
 
Here's the cam that's were putting in it.

20200312_220344.jpg
 
dieselman966 said:
Here's the cam that's were putting in it.

View attachment 1715501576
Click to expand...

That's the one! NOT XE274, it's mediocre if you want a fast acting lobe. As Wyrm will tell you, there is something to be gained from a .904 specific grind, as long as you're OK with potential wear/noise issues over a slower lobe. I personally like the XE/HL series, and have run them myself. Put the 258HL in my 440 and used a 275HL in a MoPar crate shortblock 360 (took the .508" Purple cam out) with OOTB Eddy RPM heads. Nice combo, with a LD340 intake and 3.23 gears/2500 stall in a '72 Duster.
 
yellow rose said:
I’d put that in at 109 and not 106.
Click to expand...
Readjust the valve closing......


@Wyrmrider , that’s why the builder chose that cam, safe bet, decent return, long life, low noise, perfect for a nice mild but noticeable gain for the general Hot Rodder.

LOL, I’ll actually be swinging in a lamer (Old tyme Crane) cam into a 5.9 for the above reasons. It’ll work perfect for a true and seemingly docile cruiser. Added bonus of the 1.6 rocker.
 
Been sitting on a 318 to build into a 390 for several years now with the KB 847 .030......bought the block off some one that is completely machined ...but waiting for the machine shop to open back up to probably get the decked squared....

Have Scat cast crank with Scat I beam rods ....crank is internally balanced....everything sitting there waiting...probably going to try and measure to see where the deck height is before i take it in.....
 
rumble
we don't know if the builder picked the old h or the newer hl
that h predates UDHarold
but customer ended up with the hl
IMHO cranes were smoother good for U
not a magnum I take it
The hr regrinds seem to work well
 
Wyrmrider said:
rumble
we don't know if the builder picked the old h or the newer hl
that h predates UDHarold
but customer ended up with the hl
IMHO cranes were smoother good for U
not a magnum I take it
The hr regrinds seem to work well
Click to expand...
You don’t know what cam the op got?
No worries, read below! No “HL” after the XE274.
dieselman966 said:
We got the rotating assembly back finally. Ended up right at 10:1 compression. DCR calculates out to 7.9:1 with the comp xe274 cam that the builder recommended. Should be quite the runner all said and done. We have a tc coming from ultimate converter with a stall in the 2800 to 3200 range. Do any of you have experience running a holley avenger carb? Thinking well slap on a 670 avenger.
Click to expand...
 
Bighead440 said:
That's the one! NOT XE274, it's mediocre if you want a fast acting lobe. As Wyrm will tell you, there is something to be gained from a .904 specific grind, as long as you're OK with potential wear/noise issues over a slower lobe. I personally like the XE/HL series, and have run them myself. Put the 258HL in my 440 and used a 275HL in a MoPar crate shortblock 360 (took the .508" Purple cam out) with OOTB Eddy RPM heads. Nice combo, with a LD340 intake and 3.23 gears/2500 stall in a '72 Duster.
Click to expand...
That's nice to hear. I've got a new XE275HL sitting on the shelf and was thinking about putting it in my '71 340 when I swap the J-heads out for ProMaxx 171's with 1.6 rockers. I've got 3.55 gears and a 2500 stall so it sounds like it might make for a decent combo.
 
I wish I had been paying closer attention seven years ago when I got rid of my 98 Dakota 4x4 5.2l. I would have thrown a stroker crank in that thing in a heartbeat if I was aware that there was such a thing.
 
dieselman966 said:
We have the machine work done on the 318 finally. The builder is wondering how high we want to go with the compression ratio. He is suggesting keeping it around 9.6 to 1 with the dishes pistons. Were wondering if we should push it over 10 to 1 while were at it?
Click to expand...

Kinda depends on your application and planned operating rpm, cam, timing and other stuff that requires vacuum, eh? (A nod to America's hat there...) :poke:
Your money, your build and your smiles per gallon...
 
Ottmundr said:
Kinda depends on your application and planned operating rpm, cam, timing and other stuff that requires vacuum, eh? (A nod to America's hat there...) :poke:
Your money, your build and your smiles per gallon...
Click to expand...

We ended up at 10:1 with the xe275hl cam. The truck will be used for drag racing, truck pulling and spirited cruising.
 
I've got to post some video up of this thing in action. It's really stout for 4200 pounds with 33X12.50-15s. With the NV4500 (5.61, 3.04, 1.67, 1, .74, R 5.61) you can be at a 35mph roll in third and slam into second and it will break traction and kick sideways. It runs right on par with a strong 440 in one of these trucks. With 3.92 gears & the 1.67:1 3rd (6.55:1), the 6500 rpm 95 mph third to fourth power shift breaks traction. We'll probably do 4.30 or 4.56s before too much longer.
 
Third gear pull from 35-95, not bad for 4200 pounds of rolling thunder. There may be a lot of terms to describe it, but slow ain't one of 'em!
 
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