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How much compression and quench for stock cam?

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Old 11-05-2013, 11:14 PM
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Default How much compression and quench for stock cam?

The car is going back together stock at the moment, except for LS6 intake and LT's. 2000 Firehawk. I hot tanked the 853's and lapped the valves today. The pistons have been flycut both intake and exhaust so I know my compression is going to be down some w/ the stock heads and MLS gaskets. I was considering having the heads milled and running a thinner head gasket but I didn't know how much a stock cam would take before the DCR was too high.

Any experience or insight would be helpful. Before someone says anything yes the stock heads are going on and no I'm not going to put a cam in it.

Thanks.
Old 11-06-2013, 08:44 AM
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If you don't use a cam it won't run........
Old 11-06-2013, 09:03 AM
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I'd mill .020" and run it. You're at like 8:1 DCR with stock cam IIRC. Hell degree it with 4-6 degrees advance and mill.
Old 11-06-2013, 07:48 PM
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Originally Posted by RockinWs6
If you don't use a cam it won't run........
Old 11-06-2013, 07:49 PM
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Originally Posted by JakeFusion™
I'd mill .020" and run it. You're at like 8:1 DCR with stock cam IIRC. Hell degree it with 4-6 degrees advance and mill.
OK. You have my attention. Which head gaskets?
Old 11-06-2013, 08:00 PM
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Interested to see this run. For Head gaskets, if you went with Cometic .040's you'd have better quench and it'd raise compression like you had milled your heads an additional .010. I agree with Jake, advance the cam 4*+ and let her rip. In for results!
Old 11-06-2013, 08:19 PM
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Thanks for the interest guys. I am going to call the machine shop in the morning and see how much it is to mill the heads. My "budget" build is going south. LOL.

So if it has stock heads, LS6 intake, stock cam and headers, it's just got headers right? I've been hanging around the Mustang guy at work too much....
Old 11-06-2013, 09:27 PM
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$80 is the going rate on mills around here. Should be close to that.
Old 11-06-2013, 10:15 PM
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Originally Posted by JakeFusion™
$80 is the going rate on mills around here. Should be close to that.
Why the 4-6 degree advance on the stock cam? I'm not questioning just wanting to learn.
Old 11-06-2013, 11:37 PM
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Try to bring the torque on earlier. Make it a fun car that's done by 6000RPM...
Old 11-06-2013, 11:59 PM
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Stock springs ok? stock height install height?
Old 11-07-2013, 12:03 AM
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You aren't changing the lobes

Just the cam timing.
Old 11-07-2013, 12:09 AM
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Originally Posted by JakeFusion™

Just the cam timing.
Quoted for truth.
Old 11-07-2013, 08:05 AM
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hey jake, any idea how much hp he'd pick up by going that route?
Old 11-07-2013, 08:13 AM
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Setting a tighter quench, milling the heads, and advancing the cam? He'd probably pick up a decent amount of power under the curve. I don't know a number, but just the milling and quench optimization would pick up 20ft/lbs or so throughout the RPM range. Bringing the cam timing/IVC on earlier to increase the cranking compression/DCR will help as well. Maybe 30ft-lbs under the curve for a relatively easy change that won't cost a whole heck of a lot? Somewhere around there.

I haven't seen anyone do it, but a lot of people want torque out of these engines sooner, and this is the way to do it. Although, years ago, I did see someone put LG 1-3/4" headers, milled AFR 205s, and a stock LS6 cam into a Vette and it made like 400/400 to the wheels. They added a FAST 90 to that and it was like 420/415 with a stock cam. That's a very streetable car.
Old 11-07-2013, 08:32 AM
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yea I think this is a pretty cool idea. I have never thought about going this route. Seems like a quick and cheap way to add a lil bit more power, maybe while you're saving up for a bigger build or whatever.
Old 11-07-2013, 11:07 AM
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Interested in this as well. It would be a nice way to appear/sound stock while picking up some power without sacrificing any drivability, especially with some AI 241 219cc (HCR?) heads.

Woud there be a benefit to advancing the '01-'02 cam as well?

Originally Posted by LilJayV10
So if it has stock heads, LS6 intake, stock cam and headers, it's just got headers right? I've been hanging around the Mustang guy at work too much....
Off topic... I once had a guy with a mustang tell me it was "mostly stock" and proceed to say it had headers, full exhaust, cams, and a blower...
Old 11-07-2013, 08:48 PM
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I talked to Martin@Tick about this and this was his response.

With how early the stock cam closes the intake valve your dynamic compression would be much too high with the heads milled that much and a .040" gasket.

Advancing the stock camshaft would also highly limit your peak power potential and cause the engine to peak around 300-400rpm earlier than it does from the factory.

I would install a .040" gasket, leave the heads un milled and leave the camshaft on it's intended ICL from the OEM.
Old 11-07-2013, 08:56 PM
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LS6 cam for the win!
Old 11-07-2013, 09:47 PM
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Originally Posted by LilJayV10
I talked to Martin@Tick about this and this was his response.

With how early the stock cam closes the intake valve your dynamic compression would be much too high with the heads milled that much and a .040" gasket.

Advancing the stock camshaft would also highly limit your peak power potential and cause the engine to peak around 300-400rpm earlier than it does from the factory.

I would install a .040" gasket, leave the heads un milled and leave the camshaft on it's intended ICL from the OEM.
This is exactly what I was thinking


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