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Discussion Starter · #101 · (Edited)
So my machinist had to change the springs for my new roller cam and he said that these heads aren't bad at all and that he likes Dart stuff. So if anyone is looking for a good flowing head (better then double humpers) with only 72cc chambers these are a decent head. I got these for $313 each which is a bargain price but even the current price of $353 is still very reasonable. Just thought you guys would like to know.
question :
Could a 69 camaro sport with a 250 hp 350 have come with flat top pistons?

I'm wondering because that was the 350 that was in my 66 Malibu. It came with some really lousy heads on it so we changed heads and cam. I didn't really pay attention to the pistons when the heads were off at that time but now that the motor has been torn down I see that they are flat top pistons.
Could these pistons have been original to this motor? I wouldn't think so
 

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question :
Could a 69 camaro sport with a 245 hp 350 have come with flat top pistons?

I'm wondering because that was the 350 that was in my 66 Malibu. It came with some really lousy heads on it so we changed heads and cam. I didn't really pay attention to the pistons when the heads were off at that time but now that the motor has been torn down I see that they are flat top pistons.
Could these pistons have been original to this motor? I wouldn't think so
The only difference between the L48 350/300 which I had in my 69 Camaro SS was 64cc 1.94 heads that brought the compression up to 10 to 1 and it also was a 4 bolt main with a 4 barrel. Cam and pistons were the same cast flat tops.
 

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Discussion Starter · #103 ·
This one here was/is a real oddball.
Its an "LM1" used in non ss camaros in 69.
A 69 "Camaro sport " .
Not too many of them
 

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Discussion Starter · #105 ·
That's the exact same one I'd been looking at lol
I just hadn't seen anything about pistons in there but now I know because you said they were all flat which means the pistons that were in my motor were probably the original
 

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That's the exact same one I'd been looking at lol
I just hadn't seen anything about pistons in there but now I know because you said they were all flat which means the pistons that were in my motor were probably the original
It’s there
  1. The LM1 and L48 short blocks were the same; both used the same pistons, rods, cast cranks, and camshafts. LM1's have been found with both 2-bolt and 4-bolt blocks, though it appears that most were 2-bolt blocks. Most L48's appear to have used 4-bolt blocks, but a few L48 engines been observed with 2-bolt blocks. (There is no real functional difference between a 2-bolt and a 4-bolt block at these power output levels.)
 

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Discussion Starter · #107 ·
I know . I saw that but it didn't say flat top.
I got that from you .
I'm here workin on the 70's sb and the piston in that has a dish in it. That made me wonder if someone hadn't gone in and changed pistons in the 69 block but nope .
Its because they were building for balls in 69 and panties in mid/late 70's lol
Omg those heads on that motor !
Does it get any worse than that?? Lol
882
Although I've got another set of "043" I think it is sitting over there . They might rival the 882's lol
 

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I know . I saw that but it didn't say flat top.
I got that from you .
I'm here workin on the 70's sb and the piston in that has a dish in it. That made me wonder if someone hadn't gone in and changed pistons in the 69 block but nope .
Its because they were building for balls in 69 and panties in mid/late 70's lol
Omg those heads on that motor !
Does it get any worse than that?? Lol
882
Although I've got another set of "043" I think it is sitting over there . They might rival the 882's lol
Yes my wife’s 71 Camaro SS L48 had dish. I went with .020 over flat tops with 2 valve reliefs to get a little more compression. The 69 and 70 had flat tops with 4 valve reliefs but used 64 cc heads and made 10.25 to 1. My wife’s car should come in around 9.25 to 1 with 72cc heads. To confuse you even more Al some say to stay away from high dome pistons like my L79 has because they can shroud the valves and reduce head flow. I have no clue if it really does or not.

Bill
 

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Discussion Starter · #109 ·
Yes my wife’s 71 Camaro SS L48 had dish. I went with .020 over flat tops with 2 valve reliefs to get a little more compression. The 69 and 70 had flat tops with 4 valve reliefs but used 64 cc heads and made 10.25 to 1. My wife’s car should come in around 9.25 to 1 with 72cc heads. To confuse you even more Al some say to stay away from high dome pistons like my L79 has because they can shroud the valves and reduce head flow. I have no clue if it really does or not.

Bill
For what its worth the viz don't like em at all in any application. Dome
 

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Discussion Starter · #111 ·
Vizard lol
 

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Discussion Starter · #112 ·
Instead of the fonz I call em the viz. Haha 😄
 

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Discussion Starter · #114 ·
UP to 70 was a flat top piston 4 valve relief piston. 71 and up had a dished flat top.
That's exactly what they are . Flat with 4 cuts so them are probably the ones .
Good info to know. Now I know if its an sb 70 or earlier chances are they have flattops unless someone went in there
Same for bb or ?
 

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No. BBC have domes well into the 70's....with a 119cc chamber, you've got to in order to have any compression to speak of....flat tops and 119cc chambers is about 7:1 compression in a 454, even worse in a 427 or 396.
Yeah it was the mid 70's when they dropped the compression on the big blocks and the flat tops came standard.
 
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Discussion Starter · #119 ·
No. BBC have domes well into the 70's....with a 119cc chamber, you've got to in order to have any compression to speak of....flat tops and 119cc chambers is about 7:1 compression in a 454, even worse in a 427 or 396.
More good info to put in the head computer lol
When you guys build those motors for go faster do you stick with the domes ?
Or do you use flat tops and shave the heads down to make up for the compression that would be lost by using a flat top with a 119 chamber?
 

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Discussion Starter · #120 ·
I had a 74 c10 with a 454 in it .
Would that have still been dome pistons ?
That motor was stupid in an unloaded pick up truck . Smoke the tire right off of it
 
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