speaking of HP estimates, anybody ever dyno stock 330-365-420 and what do they make?
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was the motor RATED at 420 hp output? and if you open desktop dyno and build a 454 with all stock components, does it come out 330 HP?
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If someone can give me the FULL camshaft specs for the stock 365 mag, I can see what my software gives for a number. It's considerably more in depth setup-wise than Desktop Dyno. I already have the factory GM short block modeled, just need the cam specs (that I have yet to find).
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If someone can give me the FULL camshaft specs for the stock 365 mag, I can see what my software gives for a number. It's considerably more in depth setup-wise than Desktop Dyno. I already have the factory GM short block modeled, just need the cam specs (that I have yet to find).
.004” 296*, 296*
.006” 286*, 286*
.050” 224*, 224*
.200” 130*, 130*
Valve lift with 1.7 .510”, .510”
LSA 115.5
Merc Part#431-9830 / GM#14096209
ICL 114 ATDC
ECL 117 BTDC
===============
For reference sakes, the carbureted 7.4L Merc 400 / 420 / 425 's
came with the following flat tappet cam:
Crane Part#132561 Grind # H-228/312-2S-14 T1.2
Duration at .004” : 298, 306
Duration at .050”: 228, 236
Lift with 1.7 rocker: .530”, .551”
LSA 114LSA
ICL 109 ATDC , ECL 119 BTDC assuming this info is accurate.
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I have absolutely nothing against merc . They have kids to feed too im sure . I went through the whole head scratcher on a vortec 7.4 cam deal . Then i called bob . And went ahh . The 454mag grind has to be a gm profile too but prob has the greatest potential for more with a modern roller grind from someone who eats and sleeps cam data
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Mag BBC 454/502 Flat Tappet (rect heads)
.004” 296*, 296*
.006” 286*, 286*
.050” 224*, 224*
.200” 130*, 130*
Valve lift with 1.7 .510”, .510”
LSA 115.5
Merc Part#431-9830 / GM#14096209
ICL 114 ATDC
ECL 117 BTDC
===============
For reference sakes, the carbureted 7.4L Merc 400 / 420 / 425 's
came with the following flat tappet cam:
Crane Part#132561 Grind # H-228/312-2S-14 T1.2
Duration at .004” : 298, 306
Duration at .050”: 228, 236
Lift with 1.7 rocker: .530”, .551”
LSA 114LSA
ICL 109 ATDC , ECL 119 BTDC assuming this info is accurate.
.004” 296*, 296*
.006” 286*, 286*
.050” 224*, 224*
.200” 130*, 130*
Valve lift with 1.7 .510”, .510”
LSA 115.5
Merc Part#431-9830 / GM#14096209
ICL 114 ATDC
ECL 117 BTDC
===============
For reference sakes, the carbureted 7.4L Merc 400 / 420 / 425 's
came with the following flat tappet cam:
Crane Part#132561 Grind # H-228/312-2S-14 T1.2
Duration at .004” : 298, 306
Duration at .050”: 228, 236
Lift with 1.7 rocker: .530”, .551”
LSA 114LSA
ICL 109 ATDC , ECL 119 BTDC assuming this info is accurate.
I know a lot of this could be construed as superficial, but I'd really like to test my simulation. And a baseline would be cool.
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Eveything you need is right there on the MAg cam. Just be sure where you want the events (ie: what lift)....thus why I provide .004" , .006", .050:, and .200" dur #'s when i can. So you can directly compare to other cams.
Edit in; and yes, I know you are looking for IVO/IVC/EVO/EVC. Again, it's all right there.
Edit in; and yes, I know you are looking for IVO/IVC/EVO/EVC. Again, it's all right there.
Last edited by SB; 02-04-2015 at 10:49 PM.
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Rather than having to break out the degree wheel to figure this out on paper....
Does anyone have the IVO, IVC, etc for the 365 hp cam?
Don't want to seem dense or unwilling to figure it out myself. I'd just like to respond rather quickly, and I'll be doing this on my PC at the office while trying to run our business.
Does anyone have the IVO, IVC, etc for the 365 hp cam?
Don't want to seem dense or unwilling to figure it out myself. I'd just like to respond rather quickly, and I'll be doing this on my PC at the office while trying to run our business.
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The 365s were 8.6 compression while the 420s were 8.8 compression.
"MILD THUNDER
03-23-2014, 11:34 PM
Wonder where the hp420 gets its comp bump from .I'd swear they were built like " mini hp500's' been a while since the '80s though .going to have to check da books tomarrow now curious
Like I was saying earlier, the 420HP engines were assembled at mercury hi performance back then. One of the other things done to them, was larger intake valves. The 420's had 2.25 intakes, 365 had 2.19. You are correct that they state the static compression ratio of a 454 mag at 8.6:1 in my book, and the 420 at 8.8:1. My guess is maybe they installed larger valves, custom valve job, and a little head milling.
Most guys assume a merc rect port head is the same from a 454 mag, to a 800sc, but they were assembled with different components per application."
These engines are getting old so count on the fact that they may need at least a basic refresh. Just my .02.
"MILD THUNDER
03-23-2014, 11:34 PM
Wonder where the hp420 gets its comp bump from .I'd swear they were built like " mini hp500's' been a while since the '80s though .going to have to check da books tomarrow now curious
Like I was saying earlier, the 420HP engines were assembled at mercury hi performance back then. One of the other things done to them, was larger intake valves. The 420's had 2.25 intakes, 365 had 2.19. You are correct that they state the static compression ratio of a 454 mag at 8.6:1 in my book, and the 420 at 8.8:1. My guess is maybe they installed larger valves, custom valve job, and a little head milling.
Most guys assume a merc rect port head is the same from a 454 mag, to a 800sc, but they were assembled with different components per application."
These engines are getting old so count on the fact that they may need at least a basic refresh. Just my .02.
Last edited by endeavour32; 02-05-2015 at 12:28 AM.