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Yadkin
03-27-2017, 09:29 PM
Retro-Fit Hydraulic Roller Cam. Excellent HO replacement type cam with noticeable torque and HP increases throughout the RPM range. Works with stock mass-air type injection systems.

Advertised Duration (Int/Exh): 262/270
Duration @ .050 (Int/Exh): 211/219
Gross Valve Lift (Int/Exh): .559/.559
LSA/ICL: 112/106
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 1600-5600

http://www.lunatipower.com/Product.aspx?id=3192&gid=289

This is the lowest, or "most stock" of the four that Lunati makes for this engine. After tweaking my ignition as much as I can and tuning my EFI unit I have an engine that idles good and has plenty of power.

That is to say it doesn't idle great. I'm used to old Ford V8s running extremely smooth. So smooth you can tell if they are idling, and accelerating like a turbine.

Is what I have what I should be expecting from this cam?

Joe Johnston
03-28-2017, 09:35 AM
Higher compression, aggressive timing, and a change in cam specs all can contribute to a rougher idle than a stock build. If it runs well and has plenty of power with your modifications, you may not achieve a perfectly smooth idle. Something simple like a different set of plugs or plug wires could possibly make an improvement too.

scumdog
03-28-2017, 03:32 PM
http://www.lunatipower.com/Product.aspx?id=3192&gid=289

This is the lowest, or "most stock" of the four that Lunati makes for this engine. After tweaking my ignition as much as I can and tuning my EFI unit I have an engine that idles good and has plenty of power.

That is to say it doesn't idle great. I'm used to old Ford V8s running extremely smooth. So smooth you can tell if they are idling, and accelerating like a turbine.

Is what I have what I should be expecting from this cam?

While it's not a radical cam I would still expect a slightly rougher idle.
Does the motor smooth out when the revs are increased a couple of hundred?

Yadkin
03-29-2017, 09:56 AM
While it's not a radical cam I would still expect a slightly rougher idle.
Does the motor smooth out when the revs are increased a couple of hundred?
That's the thing, it doesn't really smooth out.

Yadkin
03-29-2017, 10:02 AM
Higher compression, aggressive timing, and a change in cam specs all can contribute to a rougher idle than a stock build. If it runs well and has plenty of power with your modifications, you may not achieve a perfectly smooth idle. Something simple like a different set of plugs or plug wires could possibly make an improvement too.

The advertised compression ration for the factory was 10:1. However, measured during tear down it wasn't nearly that. This build is at 9.63:1.

My ignition timing is 16 degrees BTDC, and mechanical increase begins at 1500 RPM, up to 18 additional at 3500.

Spark plugs are one step colder than stock. Wires are new MSD Street Fire. The distributor is a Pertronix with an Ignitor II module, Flame Thrower II coil, and a Second Strike ignition box. I've tried several settings with the Second Strike, and "0" seems to work best. :confused:

simplyconnected
03-29-2017, 04:41 PM
CLICK HERE (http://www.squarebirds.org/simplyconnected/390Build/Distributor.htm)

Yadkin
04-21-2017, 04:29 PM
Here's a short video of a cold start and the idle quality.

https://www.youtube.com/watch?v=rTWb5LnW7pE&feature=youtu.be

scumdog
04-21-2017, 08:40 PM
Here's a short video of a cold start and the idle quality.

https://www.youtube.com/watch?v=rTWb5LnW7pE&feature=youtu.be

It sounded OK from behind (the exhaust note etc) but a lot of mechanical noise once you opened the bonnet!
Having said that, cameras seem to enhance any sharp sounds and minimise the deeper noises so it's not generally a true indication of the noises!

Yadkin
04-22-2017, 09:42 PM
It sounded OK from behind (the exhaust note etc) but a lot of mechanical noise once you opened the bonnet!
Having said that, cameras seem to enhance any sharp sounds and minimise the deeper noises so it's not generally a true indication of the noises!

There are mechanical noises under the hood but the camera mic accentuates the heck out of them. First you hear my water pump when cold, makes a scrape 1/revolution. Next is more rapid and I think it is the injectors.

Yadkin
04-22-2017, 09:43 PM
CLICK HERE (http://www.squarebirds.org/simplyconnected/390Build/Distributor.htm) I have a Pertronix distributor.