10:2:1 CR to low for 396?
06-02-2006, 04:17 PM
#44
Originally Posted by Old SStroker
396's cost considerably more to build correctly than 355s or even 383s
You might need a slightly larger cam and maybe slightly bigger heads for the 396 to get an optimal setup, but compared to the average cost of rebuilding a motor for machine work, ported heads, cam, etc. it's not going to be that much more for a larger size (unless you go huge like 427).
06-02-2006, 05:05 PM
#45
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Originally Posted by Speed Density
Well I found the calculator. But i dont have enough specs to make it work.
That's why a flat out "I'm not going to build you a such and such compression" does't make any sence.....Find another ENGINE BUILDER or force him to build to your spects.........
Put some different numbers in the Compression calculator such as piston cc's gasket and deck heights.....Later, try a cam with an abdc of 79 (a 847 GM cam, I believe and a good example for you, slow ramps though). You can skip the cam timing calculator section and enter the data in the Dynamic Stroke section...
06-02-2006, 05:22 PM
#46
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Originally Posted by jimbob
My point exactly...........
That's why a flat out "I'm not going to build you a such and such compression" does't make any sence.....Find another ENGINE BUILDER or force him to build to your spects.........
Put some different numbers in the Compression calculator such as piston cc's gasket and deck heights.....Later, try a cam with an abdc of 79 (a 847 GM cam, I believe and a good example for you, slow ramps though). You can skip the cam timing calculator section and enter the data in the Dynamic Stroke section...
That's why a flat out "I'm not going to build you a such and such compression" does't make any sence.....Find another ENGINE BUILDER or force him to build to your spects.........
Put some different numbers in the Compression calculator such as piston cc's gasket and deck heights.....Later, try a cam with an abdc of 79 (a 847 GM cam, I believe and a good example for you, slow ramps though). You can skip the cam timing calculator section and enter the data in the Dynamic Stroke section...
06-02-2006, 07:21 PM
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Originally Posted by dhdenney
Whilst we're on it, how do you figure deck height on an already built motor? I was playing with the calculator doing the same thing but I need the PTD. (See related thread "Fun with numbers---->DCR.")
I bought some Probe pistons and now have a deck height of .011...perfect for a .029 gasket... 
You'll only get those numbers from measuring with the heads off....You can take a guess if you know your engine deck has been cut or not, and what pistons your using....
06-02-2006, 08:17 PM
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Originally Posted by jimbob
My 396 "Old combo" had a deck height of .018 with a .020 cut on the block (SRP .030 over -14cc pistons) You can see my stock deck height before surfacing/decking was quite hi, numbers---bad...Actually, I measured stock piston height before build and it was .036 I bought some Probe pistons and now have a deck height of .011...perfect for a .029 gasket... You'll only get those numbers from measuring with the heads off....You can take a guess if you know your engine deck has been cut or not, and what pistons your using....
I bought some Probe pistons and now have a deck height of .011...perfect for a .029 gasket... You'll only get those numbers from measuring with the heads off....You can take a guess if you know your engine deck has been cut or not, and what pistons your using....
06-02-2006, 09:01 PM
#50
.029 would be a good day at the factory. we have measured many LT1s over the year and .028 was about the BEST we got out of one 
most are in the mid .03x area
Now seeing you have a 396 already I would go ask the builder. any builder worth his salt should be able to tell you and have it recorded some where...like on your recipt
most are in the mid .03x area Now seeing you have a 396 already I would go ask the builder. any builder worth his salt should be able to tell you and have it recorded some where...like on your recipt
06-02-2006, 09:16 PM
#51
Using feeler gauges and a small straightedge which is admittedly not the best way we got more like .022 on my motor. Would not suprize me if proper measuring techniques netted a .025 measurement but I don't think there is any way it was even near .030.
06-02-2006, 11:11 PM
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Originally Posted by TwoFast4Lv
.029 would be a good day at the factory. we have measured many LT1s over the year and .028 was about the BEST we got out of one most are in the mid .03x area
Now seeing you have a 396 already I would go ask the builder. any builder worth his salt should be able to tell you and have it recorded some where...like on your recipt
most are in the mid .03x area Now seeing you have a 396 already I would go ask the builder. any builder worth his salt should be able to tell you and have it recorded some where...like on your recipt
I looked on my receipt that I dug out and all it said in regard to the block was "notch for stroker" and "bore block." I thought they were reputable when I started this thing in 2002 which is why I took it there. If I ever get enough $$ for an LSx, I will be buying a sponsor shortblock. Surely they decked it a little just to clean it up but I'm sure it would be on the receipt. I'm sure calling them would do a lot of good. They told me 10.8 so I am assuming the .029" is correct because it's the only value I didn't have and it's what makes the formula work. My DCR is like 8.1 which sucks but if I had never seen this forum I wouldn't have known the difference. Judging from my dyno charts, had my opti been good at the time I would have made ~400 rwhp at 6000 rpm. Surely this bitch will peak higher than that though. Even though I now have a nitrous ready shaft and an A4, I believe 400 rwhp peak is still in the market. Nothing to complain about I don't guess.
06-04-2006, 11:56 AM
#54
Originally Posted by infinitebird
How do you figure that? I disagree.
You might need a slightly larger cam and maybe slightly bigger heads for the 396 to get an optimal setup, but compared to the average cost of rebuilding a motor for machine work, ported heads, cam, etc. it's not going to be that much more for a larger size (unless you go huge like 427).
You might need a slightly larger cam and maybe slightly bigger heads for the 396 to get an optimal setup, but compared to the average cost of rebuilding a motor for machine work, ported heads, cam, etc. it's not going to be that much more for a larger size (unless you go huge like 427).
Bret
06-04-2006, 11:59 AM
#55
Originally Posted by 96capricemgr
Far as OldSStrokers comments on port volume he is Bret Bauer's(as in LE's cam guy) father so he is a bit biased. AI manages to make good power with "small" ports and that is the "theory" I have long believed best and why they got my money, Lloyd uses a good bit more port volume and his customers make good power too. Comes down to more than one way to skin a cat. They both have happy customers going fast enough to turn heads at the local track and daily drivers beating trailered "race" cars.
We've been doing that with SBC's long before I was ever hooked up with Lloyd. So don't think he's "biased" because of AI, lol.
Most people would think that 215cc heads on a 358 are way to big, and can't make power or TQ... coulda fooled the dyno though.
Bret
