364" SBC engine.

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cardo0
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Re: 364" SBC engine.

Post by cardo0 »

KnightEngines wrote: Thu Apr 04, 2019 8:18 pm Lj 3.48 crank offset ground to sj & 3.57" stroke with 4.03" bores.
That's a legacy for a stroker from when the older/ smaller journal rods where used. Machine shop needs to offset grind the rod journals for 2.00" rods and a 1.56" compressed height piston. And I don't know which is more difficult to find: a machine shop that can offset grind the crank by 0.080" or a 1.56" compressed height piston? One of my favorite shops said they could offset grind the cranks rod journals a full 0.100" which made me walk (0.080" is all you gonna get or want). Oldest m/s in town still does this though but it's in a high crime area that I don't care for.
For a piston Sil-O-Vite has some hypers up to 0.060" overbore with a 1.56" compressed height (part number 3437HC). 1.56 d/h puts the piston up neer the top of the deck on a 9.025" block.
74 corvette: 350 4 speed
94 Z28: Gen II 350 auto
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Re: 364" SBC engine.

Post by pdq67 »

Why not use a 400 blo9ck and a stroke to get the size wanted?

I would think better valve breathing is all.

Like my 325", --- 4.155" X 3.00" engine.

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Re: 364" SBC engine.

Post by KnightEngines »

The 364 cube engines I've built have been holdens with chev rod journal cranks, they are a 4" bore engine & have shorter deck height, so there is an off the shelf chev piston that works with a 6" sj chev rod.
4.125" bore is not an option unless you want to spend $8k on a block....
Many road race classes over here are still limited to 6l capacity unless you want to play with the big boys in unlimited with their all wheel drive 400+ cube and or turbocharged monsters & budgets in the "my house cost less" category!
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Re: 364" SBC engine.

Post by fdicrasto »

cardo0 wrote: Fri Apr 05, 2019 3:00 pm
KnightEngines wrote: Thu Apr 04, 2019 8:18 pm Lj 3.48 crank offset ground to sj & 3.57" stroke with 4.03" bores.
That's a legacy for a stroker from when the older/ smaller journal rods where used. Machine shop needs to offset grind the rod journals for 2.00" rods and a 1.56" compressed height piston. And I don't know which is more difficult to find: a machine shop that can offset grind the crank by 0.080" or a 1.56" compressed height piston? One of my favorite shops said they could offset grind the cranks rod journals a full 0.100" which made me walk (0.080" is all you gonna get or want). Oldest m/s in town still does this though but it's in a high crime area that I don't care for.
For a piston Sil-O-Vite has some hypers up to 0.060" overbore with a 1.56" compressed height (part number 3437HC). 1.56 d/h puts the piston up neer the top of the deck on a 9.025" block.
Way back when, the offset stroked 3.48" crank to small journal rod throw was a legitimate deal and TRW offered an off the shelf piston for that 364" combo.
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Re: 364" SBC engine.

Post by Walter R. Malik »

cardo0 wrote: Fri Apr 05, 2019 3:00 pm
KnightEngines wrote: Thu Apr 04, 2019 8:18 pm Lj 3.48 crank offset ground to sj & 3.57" stroke with 4.03" bores.
That's a legacy for a stroker from when the older/ smaller journal rods where used. Machine shop needs to offset grind the rod journals for 2.00" rods and a 1.56" compressed height piston. And I don't know which is more difficult to find: a machine shop that can offset grind the crank by 0.080" or a 1.56" compressed height piston? One of my favorite shops said they could offset grind the cranks rod journals a full 0.100" which made me walk (0.080" is all you gonna get or want). Oldest m/s in town still does this though but it's in a high crime area that I don't care for.
For a piston Sil-O-Vite has some hypers up to 0.060" overbore with a 1.56" compressed height (part number 3437HC). 1.56 d/h puts the piston up neer the top of the deck on a 9.025" block.
.095" is done all the time and if you want to go .020" under 2.00", .115" is perfectly acceptable.

ANY quality crankshaft man can probably do this.

Pistons can be made with almost ANY compression height.
And, as has been said; several shelf stock forged pistons were available for that combination using 5.7" or 6.0" rods.

You must still be living in the 70's, LOL
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Re: 364" SBC engine.

Post by DeezNutz »

Alot more unconventional but you can get there with a bore of 3.93 (.060 over 307) and a 3.75 stroke. John Beck built a few of these for the engine masters challenge back somewhere around 2005??? I think Beck's 307 stroker came in 3rd place at engine masters.
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Re: 364" SBC engine.

Post by cardo0 »

Walter R. Malik wrote: Sat Apr 06, 2019 11:43 pm
.095" is done all the time and if you want to go .020" under 2.00", .115" is perfectly acceptable.

ANY quality crankshaft man can probably do this.

Pistons can be made with almost ANY compression height.
And, as has been said; several shelf stock forged pistons were available for that combination using 5.7" or 6.0" rods.

You must still be living in the 70's, LOL
[/quote]

Well the 70's had some great ideas for the sbc. And the 9/16 stroker is overlooked today with all the cheap 3.75" cranks available.

But for me I wanted to reuse my Gen II crank anyways as a budget build and save $$$ from a alignhone/alignbore. Better rods where a wash from rebuilding the stock rods with new bolts so why not small journal 2.00 rods and offset grind the crank for the extra stroke. And the block doesn't even need to be relieved for the extra stroke.

Thanks for posting those offset numbers as it got me to crunch the needed compressed height again and I can see the more common 1.54" piston compressed height works for a 9/16" stroker leaving 0.005" on the deck for a shave. Gotta love those Sil-O-Vite piston prices for hypers with coated skirts also - something less than 150 bucks if you price shop. I guess what I'm saying here is the budget stroker is using 0.080" offset for 0.040" more stroke - allows cheaper pistons and may even save from decking the block. The more you offset the journal the more expensive it gets and may not be worth the effort with current prices for on the shelf stroker cranks and matched pistons/rods.
74 corvette: 350 4 speed
94 Z28: Gen II 350 auto
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Re: 364" SBC engine.

Post by amc fan »

4.00x3.625 =364
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Re: 364" SBC engine.

Post by MadBill »

cardo0 wrote: Sun Apr 07, 2019 12:28 pm... I guess what I'm saying here is the budget stroker is using 0.080" offset for 0.040" more stroke...
But an offset of 0.080" (grinding 0.080" off at the 6 o'clock position and zero off the 12 o'clock) increases the throw by 0.040" and so the stroke increases by 0.080".
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Re: 364" SBC engine.

Post by cardo0 »

MadBill wrote: Sun Apr 07, 2019 10:21 pm
cardo0 wrote: Sun Apr 07, 2019 12:28 pm... I guess what I'm saying here is the budget stroker is using 0.080" offset for 0.040" more stroke...
But an offset of 0.080" (grinding 0.080" off at the 6 o'clock position and zero off the 12 o'clock) increases the throw by 0.040" and so the stroke increases by 0.080".
Yes your right Bill. Full stroke on a full revolution of the crank will be 0.080". I guess what I meant was 0.040" higher in the hole when I was calculating for compressed height. On a 0.080" stroke increase the piston is only 0.040" higher - which puts it within 0.005" of the top of the deck using 5.7" rods and 1.54" compressed height pistons on a stock 9.025" block (but it also pulls 0.040" further down the cylinder hole).
74 corvette: 350 4 speed
94 Z28: Gen II 350 auto
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