Ghost Cam Query

[WildHorse]

You sure it's dumping fuel ? I think it's firing off the spark late relative to cam position. Which would send some unburnt fuel through the exhaust.

I had a 440 with a big ole .690 lift cam w/ 1.6 rockers. 8 degree Idle timing got you that 'lumpy potato' 800 rpm idle. Locking out the distributer and setting the timing at say 28 degrees got a relatively smooth 800 rpm idle.

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[HKusp]

Where else is that unburnt fuel going if it's going out of the exhaust? You don't think any of it remains on the cylinder wall?

 

[K4fxd]

Run any engine long term when it’s dumping fuel into and washing down the cylinders as well as the rotating assembly, it’s going to fail….

It's not a big deal with gas but E85 it is. Done right anyway.

ou sure it's dumping fuel ? I think it's firing off the spark late relative to cam position. Which would send some unburnt fuel through the exhaust.

The added overlap sends raw fuel into the exhaust.

I had a 440 with a big ole .690 lift cam w/ 1.6 rockers. 8 degree Idle timing got you that 'lumpy potato' 800 rpm idle.

I'm an old Mopar or no car guy. The engine wouldn't idle on 8 degrees initial. If it did it would sound like an old twin cylinder John Deere tractor. Hell even the old 509 cam wanted 20 at 900 RPM

 

[WildHorse]

I'm an old Mopar or no car guy. The engine wouldn't idle on 8 degrees initial. If it did it would sound like an old twin cylinder John Deere tractor. Hell even the old 509 cam wanted 20 at 900 RPM

Lol k. . Had my base set it 8. I elongated the slots on the weights for 20 degrees total. Deleted the vac advance. Idled all day like that.

 

[K4fxd]

Had my base set it 8. I elongated the slots on the weights for 20 degrees total. Deleted the vac advance. Idled all day like that.

I always set the initial at 18 to 20 and set the total at 36 to 40 for the big blocks. Light springs to bring it in at 2000.

Anything less and it wouldn't take throttle. This is with big cams, single plane manifolds and Holley carbs. 906 heads and I always ported them using the DC porting template.

 

[WildHorse]

I always set the initial at 18 to 20 and set the total at 36 to 40 for the big blocks. Light springs to bring it in at 2000.

Anything less and it wouldn't take throttle. This is with big cams, single plane manifolds and Holley carbs. 906 heads and I always ported them using the DC porting template.

28 cause it was 11.5:1 cr. TM7 intake, 915 heads, Holley 850 DP w/ PV blocked 78 jets on all 4 corners.

 

[K4fxd]

Depending on the engine I was running 10 up to 13 to one compression. I also used 110 or 105 octane pump gas or actual race gas.

 

[WildHorse]

I also used 110 or 105 octane pump gas or actual race gas.

100LL.

 

[K4fxd]

100LL.

I tried AV gas in the 1970's when the good stuff went away. Didn't work very well. Not volatile enough.

 

[HKusp]

Just curious, what were the tolerances and weight of oil you guys used on those old Mopar engines? How many miles a year did you put on them? How many miles between oil changes?

 

[K4fxd]

I used Valvoline 40 wt then went to 20-50. 3000 mile intervals and I would need to rebuild every 50,000 for the street motors. If I built one sane it would last 100K or more.

I daily drove mine. I would swap between a 1970 RR and a 1970 'Cuda then I had my 72 D100. This S550 reminds me a lot of the 'Cuda. I had a bunch of parts and race cars also.

 

[WildHorse]

Just curious, what were the tolerances and weight of oil you guys used on those old Mopar engines? How many miles a year did you put on them? How many miles between oil changes?

Tolerances were very loosie goosy.. like .035 on the mains. I used 20w50 cause frankly that's the only way to get decent oil pressure. Even with high pressure pumps. High volume sucked the pan dry ha-ha. Changed oil every 2-3000 miles, prolly drove it 3000 miles a year.

 

[BombZombie]

This isn't answering any of your questions OP, but...I'm not a fan of the ghost cam thing, and I usually appreciate some pretty unnecessary sh!t. (Also, my overall opinion doesn't really matter anyhow)

My buddy had a ghost cam in his 2012 and had accidentally locked his keys in the vehicle while it was running. While comical at first, it got real old after listening to his car chop for 45 minutes straight while waiting for the locksmith/tow...it also smelled bad.

That was enough to make me not like the "novelty" of a ghost cam tune.

 

[WildHorse]

I tried AV gas in the 1970's when the good stuff went away. Didn't work very well. Not volatile enough.

Obviously you didn't try 100LL

 

[K4fxd]

100LL is Aviation fuel. Pretty much the best you can get these days. You used to be able to buy it by color. I forget what the colors were but there was 100 octane 110 octane and 115 or 116.

The LL equals low lead. It is the min amount of lead to keep the valves happy.
The vapor pressure of the AV gas is too low for use on the ground.

Yes it will run the car, but not very well.

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