What compression............
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From: East Side Performance! mASShole
Re: What compression............ Im interestd in the same thing, Im hereing 8.5 for pump gas. Dont know for sure. I think if you can get more cubes you can go with a little higher comp, Im in the same boat right know, I got som disitions to make soon.
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From: F.H,Waterford,Port Huron, MI
Re: What compression............ Well I was told that it is not as good to go under 9.0.1 for street use as it kills the car out of the hole? Harlan is at 8.7.1. But if your turbo spools at 2500RPMS does it matter?
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From: East Side Performance! mASShole
Re: What compression............ Im hering about the same, 8.5 dog for the street. 9-1 not safe, Im thinking right in th middle, 8.75-1.
But not 100% just yet.
But not 100% just yet.
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From: F.H,Waterford,Port Huron, MI
Re: What compression............ where you on a stock lower end with the 9.1.1 at 6lb. I had stock block with 6.0 heads. 10.5lb. So after I find out what compreesion everyone has I what to see what boost I will be at 15lb.
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From: F.H,Waterford,Port Huron, MI
Re: What compression............ well is there a way to make up for low compression. I mean ok "more boost" but am I going to need a BOV. Oh and I still have the 2 stage NOS (where at 40each)but are uping it! These is a 348ci block
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From: Raleigh, NC
Re: What compression............ I don't know if it is an issue for Turbos, but ATI recommends no higher than 12 PSI for an engine at 9.5:1 static compression.
They say a 9.0:1 compression engine may safely run about 17 PSI of boost.
Of course, lower compression allows more boost, but street engines can be sluggish out the hole with very low compression. Larger cubed motors can help because they have more torque.
So much to consider...
They say a 9.0:1 compression engine may safely run about 17 PSI of boost.
Of course, lower compression allows more boost, but street engines can be sluggish out the hole with very low compression. Larger cubed motors can help because they have more torque.
So much to consider...
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From: F.H,Waterford,Port Huron, MI
Re: What compression............ So it sounds like most people are going for 9.1.1 but what boost and what fuel seems to be the real question? I don't want to go higher than 93 pump gas.
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Re: What compression............ I also have Diamond dished -8.6cc pistons with A&A stage II CNC heads. A&A estimates compression at 9.25:1. I'll know how it works when I put it together.
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From: Chi-Town, IL
Re: What compression............ I'm not sure exaclty what dish my diamonds are...but my heads have 73cc chambers, so I figure I'm 9:1 or lower....running 93 octane, trying to run 12psi....going good so far, just can't keep the belts together...
Re: What compression............ Hey Brian just email cgelineau@diamondracing.net and he should be able to tell you.
Re: What compression............ My new motor is 8.5:1, but it is a 404. I figured that the loss of low RPM driveability due to the compression would be replaced by the extra cubes.
Re: What compression............ im at 8.9:1 i figure ill be using 12-13psi on 94 octane.
i figured you would have gotten your engine together sooner. whats taking so long?
i figured you would have gotten your engine together sooner. whats taking so long?
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From: F.H,Waterford,Port Huron, MI
Re: What compression............ Crower lost my rods $1300 billet steel rods where finaly found in a stock pistion spec box on there shelf. I also got bigger turbos and more NOS so I can't wait!! 
Re: What compression............ 9:1 compression *should* be good up to 14 psi on pump gas (93 octane) from what I have seen.
2 FAST 4U if you give me your engine specs I will give you your compression ratio.
It is important to know exactly what it is. We had a mustang folk in here the other day that built his own engine. He wasn't paying close attention when he specked everything out and ended up with a 7.5:1 compression
At first, we had a hell of a time figuring out why he only made 190 HP on the dyno.
2 FAST 4U if you give me your engine specs I will give you your compression ratio.
It is important to know exactly what it is. We had a mustang folk in here the other day that built his own engine. He wasn't paying close attention when he specked everything out and ended up with a 7.5:1 compression
At first, we had a hell of a time figuring out why he only made 190 HP on the dyno.
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From: F.H,Waterford,Port Huron, MI
Re: What compression............ heads are ported stock heads 64cc? -11cc head gaskets and I will have to check the pistions but we told JE to get Flat top 9.3.1 and then gas port them -2.8 so to be honest I have no idea but I think they are 9.1.1 to 8.9.1 with .20 deck height?
Re: What compression............ 2FAST4U:
I tried crunching those numbers, but they didn't really work out to anything around 9:1
If you get the chance, I need
Head CC (above looks good)
Bore Size (if stock just say so)
Stroke length (if stock just say so)
Piston Dish
Head Gasket Thickness (never heard of a -11cc head gasket ?)
Piston Rise (stock is .01 out of the bore)
With that cc on your head, and the stock cubes, most people have to run a 10 to 14 cc dish in the piston to get the compression down around 9:1
I tried crunching those numbers, but they didn't really work out to anything around 9:1
If you get the chance, I need
Head CC (above looks good)
Bore Size (if stock just say so)
Stroke length (if stock just say so)
Piston Dish
Head Gasket Thickness (never heard of a -11cc head gasket ?)
Piston Rise (stock is .01 out of the bore)
With that cc on your head, and the stock cubes, most people have to run a 10 to 14 cc dish in the piston to get the compression down around 9:1
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From: F.H,Waterford,Port Huron, MI
Re: What compression............ heads 64cc, head gaskets msl 6.0, flat top pistions with gas relief of -2? stock length rod, And I asume stock everything else? THANKS