416 W2 on the dyno w/cam swap

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RAMM

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The rundown: 360 block circa 1977 4" Eagle 4340, Scat I-beams, Icon 745 pistons, Custom Comp roller 246/244 .050" 660"/660" 106, Scorpion hydraulic lifters, Rollmaster timing chain, W2 closed chambers heads 60cc flow 292-298 cfm @ .600-650" Eddy Victor 340 W2, 830 Holley annular .5" open spacer and the only headers I had to test with-Schoenfeld 1 5/8-1 3/4" in the LA exhaust pattern!

Unspoken power goals were 600hp and 550+ft/lbs on 91 pump fuel.

So after the intial fire up and abbreiviated pulls all looked good after an inspection under the valve covers. While I did not have a provision to measure manifold vaccuum I am sure it was 5-6" as it had a very rough idle. Pulls were made from 3500-6200rpm. I am fairly certain the large mismatch created by the LA style headers and the smallish size corked up a small amount of power. How much power? Who knows?

All testing was done with Esso 91 pump fuel (probably winter blend-yuck) at 36 total timing locked out. After several pulls in the 570+hp range it was apparent that 600+hp wasn't about to show up without some work. I really wasn't too thrilled with the poor idle quality considering I have this engine sold to a street bound customer I was worried about true driveability. I started to think at this point that maybe a cam swap was in order. Upon intake manifold removal and lifter removal I discovered a collapsed lifter on the #4 intake-OK that would hurt power some I would imagine. At this point the engine is getting new lifters and a different cam but not a custom cam. I decided to use a Lunati VooDoo 243/251 grind which would bring the valve lift into a more steet friendly range and with the 110 LSA should bolster idle vaccuum and driveability. Here are some pics-'cuz it happened. J.Rob
 

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Here's the dyno results after the swap to the Lunati cam and new Scorpion lifters. Pretty interesting. J.Rob
 

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So as you can see I did not in fact reach the magic 600hp mark, but I am not too concerned with that as the engine exhibits a much better "personality" and a little more power with a smaller cam. The customer is investing in some fairly trick true W2 exhaust headers that I am fairly certain could let this engine crest 600hp.

I have to remind myself sometimes that I have built less powerful big blocks than this small block in the past. Incredible how torquey the 408/416 package can be with off the shelf parts. J.Rob
 
Very cool. Thanks RAMM. I still feel the ultimate combo is the A body with a 4" stroker.
 
Like I have been saying, them Voodoo cams kick ***. And you were running a lot leaner on the Voodoo cam, if you richened it up to the comp run you would have seen 600HP.

You were making 590HP with 236.9 lb per hr where with the comp cam you were making 578HP with 245.9 lb per hr.

Less fuel more power! If you had the Voodoo setup with the same fuel consumption,600+ all day long.

Nice setup
 
MRL Performance said:
Like I have been saying, them Voodoo cams kick ***. And you were running a lot leaner on the Voodoo cam, if you richened it up to the comp run you would have seen 600HP.

You were making 590HP with 236.9 lb per hr where with the comp cam you were making 578HP with 245.9 lb per hr.

Less fuel more power! If you had the Voodoo setup with the same fuel consumption,600+ all day long.

Nice setup
Click to expand...

I too promote the Voodoo cams whenever I can--they work well. Something else to consider are the averages . With the Lunati the average torque and horsepower were up by 5+ each over the same RPM span. Win win. I realize that about the fuel as well and may try it as I still have it on the dyno. However between the customer picking it up and other work I doubt I will find the time. Thanks for the comments. J.Rob
 
awesome build makes me anxious to get my 416 on the dyno close engine to yours just fully ported eddies from hughes and mike at mrl been helping with the cam setup and other parts, congrats
 
Very nice combo. Do you know what the lift was on this cam at the lobe or valve(with 1.5 or 1.6 rockers). Also what sort of power increase do you think the roller is worth over a flat tappet solid?

I have a 248@50 comp solid flat tappet with 540 net lift in mine with unported w2s and I think there must be a lot left on the table with my cam and unported heads compared to your combo. Mine seems to be around 450 to 460hp at the moment.
 
evil66 said:
Very nice combo. Do you know what the lift was on this cam at the lobe or valve(with 1.5 or 1.6 rockers). Also what sort of power increase do you think the roller is worth over a flat tappet solid?

I have a 248@50 comp solid flat tappet with 540 net lift in mine with unported w2s and I think there must be a lot left on the table with my cam and unported heads compared to your combo. Mine seems to be around 450 to 460hp at the moment.
Click to expand...

Lift was .616"/.622" at the valves. Estimating a power difference between a roller and a flat tappet is extremely difficult-if not impossible. My WAG would be "Not as much as you think" over the RIGHT flat tappet.

Sounds like you have the Comp 294S . That is a pretty good cam in my experience. W2's NEED to be ported--they stall hard and early. The good news is that they are very easy to improve upon. J.Rob
 
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