gottago wrote: ↑Mon Dec 10, 2018 5:12 pm
In regard ..
The easiest way DV explains it is lc is linked to compression ratio. The higher the compression the smaller the chamber volume to scavenge. So the smaller the overlap triangle needs to be and the wider the lc. Thanks, Charlie
But 118 lsa is going quite a ways past the recommendations in DV formula for that aspect.. Not saying the results aren't real nice, just that its not totally explained by the compression ratio /lsa.. 118 lsa installed slightly retarded is so different from most recommendations you usually hear that it makes me wonder. Do you have any dyno numbers from the lower rpm range 3000-5000 ? Does it fall off real fast or drop unusually low anywhere in comparison the usual alternate cam choices?
I have used all the vortecs at one time or another. Currently EQ.. I have been running wider and wider lsa each time with decent results. Never beyond 113 lsa though. The vortecs "seemed" to like that more so than some other heads. Sorry no dyno #s , just curious.
i agree with the previous Post as it was stated,
but i do not agree 100% with DV LSA formula
Do you have any dyno numbers from the lower rpm range 3000-5000 ?
Does it fall off real fast or drop unusually low anywhere in comparison the usual alternate cam choices?
I have used all the vortecs at one time or another. Currently EQ..
I have been running wider and wider lsa each time with decent results.
Never beyond 113 lsa though. The vortecs "seemed" to like that more so than some other heads. Sorry no dyno #s , just curious.
these Dyno tests are the only time we made Dyno Pulls
befow 5000 RPM starting point :
He runs a 5000+ Stall Converter in the Mud Truck
we only started this Dyno Pull this low in RPM
because it had only 10.8:1 CR ( along with Q16 Gas )
so no chance of harming the engine at all
SBC Mud Truck
4.030x3.480=355.2 CID
ProMaxx Vortec Heads 2.055/1.600
Edelbrock Vortec Super Victor
Q16 Race Gas
10.8:1 CR
CompCams 5980/5985 118 251/247 .363/.363 118 Centers 116.5 CL
1.52 Roller Tip Steel Rockers
38 BTDC
LAT 20/50 Breakin Oil
Custom Kickout Oil Pan 10 Qts Oil
unmilled ProMaxx Heads
Peak TQ = 433.3 at 4800 RPM
Peak HP = 476.4 at 6500 RPM
So this is the smallest Cubic Inch Mud Truck engine we ever built/Dyno tested
i think it did really great for only 10.8:1 Compression Ratio , all things considered
476.4 Peak HP / 355.2 CID = 1.341216216 HP/CID Ratio
525.9 Peak HP = best Engine Combo at 361.5 CID
-476.4 Peak HP at 355.2 CID 10.8:1 CR
------------------
49.5 Peak HP difference
Compared to one of our best Engine Combos :
1.341216216 HP/CID Ratio x 361.5 cid = 484.8
so about 484.8 Peak HP if it were 361.5 CID engine size
then Angle-Mill the Heads 0.000-0.085" for almost 12.5:1 CR
12.5 - 10.8 = gain 1.7 points in Compression Ratio
then go from Q16 Race Gas to higher HP C45 Race Gas
then go from 1.52 Rocker Ratios to 1.72 Rocker Ratios
then lighter LAT Race Oil from LAT 20/50 Breakin Oil
and it should end up around 526 Peak HP
Note : CompCams 5980/5985 118 251/247 .363/.363 118 Centers 116.5 CL
Cam was on 116.5 IntCL and had 118.0=LSA
still made a lot of Torque
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