The only difference between a Camaro LT1 and a Corvette LT1 that I'm aware of is a 4 bolt main.
Edelbrock 1407 off idle bog
- Thread starter Baker7888
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The only difference between a Camaro LT1 and a Corvette LT1 that I'm aware of is a 4 bolt main.
I did some digging around and came up with same thing.
Not very good info on the heads themselves and came up with three different values for Chamber CC. I Attached the workups.
Chamber CC as investigated was; 58, 64 or 68. The Chamber value has the greatest input on compression ratio (CR). Because of this you end up with a Static Compression Ratio (SCR) between 8.98 to 9.98.
All of the above is based off of current information available. Using the Camshaft info you supplied and known GM engineer data, you end up with a Dynamic Compression Ratio (DCR) of 8.48. Theoretically you want to try to stay 7.5 to 8.0, but 8.48 you are still ok.
Theoretically 8.5 is the highest you want to go.
The DCR is also based on some estimates such as CC for the 4 Relief Piston as 5 CC. The .040 deck clearance is based on GM data of the LT1, per OEM design data. The gasket crush of .041 is based on OEM Felpro over the counter retail. Felpro also has the "Pro" set that crushes to .020. If those were used, or something similar, your SCR goes up to 10.2.
Not very good info on the heads themselves and came up with three different values for Chamber CC. I Attached the workups.
Chamber CC as investigated was; 58, 64 or 68. The Chamber value has the greatest input on compression ratio (CR). Because of this you end up with a Static Compression Ratio (SCR) between 8.98 to 9.98.
All of the above is based off of current information available. Using the Camshaft info you supplied and known GM engineer data, you end up with a Dynamic Compression Ratio (DCR) of 8.48. Theoretically you want to try to stay 7.5 to 8.0, but 8.48 you are still ok.
Theoretically 8.5 is the highest you want to go.
The DCR is also based on some estimates such as CC for the 4 Relief Piston as 5 CC. The .040 deck clearance is based on GM data of the LT1, per OEM design data. The gasket crush of .041 is based on OEM Felpro over the counter retail. Felpro also has the "Pro" set that crushes to .020. If those were used, or something similar, your SCR goes up to 10.2.
Attachments
The land yachts got the LT1 with large chamber iron heads, don't let those confuse you. The aluminum headed F/Y bodies should have been right around 10.5:1. The 2 bolt block was the same between those, same crank, same pistons, same rods, different cam. There was also an iron headed 4.3L V8 LT1 lookalike.
Thanks for the info. What does all this mean, specifically why do I want to keep dynamic CR below 8.5? How does this correlate to the off idle bog, thought this was largely due to over carbed motor?? Also it is widely stated across the internet that a 96 lt1 has a 10.4:1 CR so is that incorrect?
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Everything I sent was based on current knowns, with some estimations. This creates the ranges I sent.
The DCR has more to do with drivability and potential to donate or knock. I gets in deep with how the cylinder fills itself, hangs on to what it has and develops power. I don't get too deep into it either, but from research and other folks I am told 7.5 to 8 is where to target. That's why I keep it in the "Theory" bracket. It might be different if I had my own dynometer and could experiment on my own, but I don't.
As the piston comes up starts compression and moves down to convert reciprocal motion to rotational Force is where the concern is.
In your case is how much fuel, how much timing, ...where and when. This will be relegated to vac gauge, A/F gauge and timing light. Ultimately the end result will be measured by stopwatch and seat of the pants feel, and are you happy with what you have.
Wait until the 1405 comes in and go from there.
There was a posted concern about cam, but .510 at 230, I don't see as major problem. Maybe and... Maybe a little more duration? But at what cost? And what would be the benefit? I don't see anything mechanical or radical that needs changed.
As far as 10.4 as stock... I'm not seeing it, I looked and haven't found it except with only one scenario.
---> 58 CC Chamber, .020 in the hole and .020 crush gets you 10.2
The DCR has more to do with drivability and potential to donate or knock. I gets in deep with how the cylinder fills itself, hangs on to what it has and develops power. I don't get too deep into it either, but from research and other folks I am told 7.5 to 8 is where to target. That's why I keep it in the "Theory" bracket. It might be different if I had my own dynometer and could experiment on my own, but I don't.
As the piston comes up starts compression and moves down to convert reciprocal motion to rotational Force is where the concern is.
In your case is how much fuel, how much timing, ...where and when. This will be relegated to vac gauge, A/F gauge and timing light. Ultimately the end result will be measured by stopwatch and seat of the pants feel, and are you happy with what you have.
Wait until the 1405 comes in and go from there.
There was a posted concern about cam, but .510 at 230, I don't see as major problem. Maybe and... Maybe a little more duration? But at what cost? And what would be the benefit? I don't see anything mechanical or radical that needs changed.
As far as 10.4 as stock... I'm not seeing it, I looked and haven't found it except with only one scenario.
---> 58 CC Chamber, .020 in the hole and .020 crush gets you 10.2
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Strictly based on estimation, what are your thoughts/expectations for the 600? Should be here for the weekend. The 750 cruised nicely and hit hard at WOT. After drilling the idle pickup tubes, the off idle stumble was greatly improved but not completely gone.
Secondaries on the 600 are the same as the previous 750.
Fingers crossed, but would expect better low RPM operation while high RPM operation would be same or very similar. The primary boosters are already modified, so I would swap those and see if they effect change or not.
Fingers crossed, but would expect better low RPM operation while high RPM operation would be same or very similar. The primary boosters are already modified, so I would swap those and see if they effect change or not.
Are you saying swap the modified primary boosters on to the 600?
Shouldnt i just try it as-is first?
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