Unexpected gains with cam swap
06-15-2020, 08:38 PM
#23
Rwhp? So a little while ago I saved up some funds to build up a decent streetable h/c setup, my research led me to picking up a Texas Speed 228r cam on 114lsa and matched it up with the PRC 5.3l ported heads.
I was pretty happy with the results, expected to hit 400hp, but ended up with 429hp/389tq, which made me happy... but of course, I "needed" more...
The need for more came before any funds were available for buying "more"; throwing more monies into my build to work out flaws was not an option. I did however have a slightly 'larger' cam lying in my garage.
The 228r cam that put me at 429hp was spec'ed at: 228/228 588/588 114lsa, the 228r cam uses the aggresive comp xer lobes. Power with this cam peaked at about 6100rpm
The rogue cam in my garage was reground by deltacams to 228/230 .571/.573 112lsa, and has the less aggresive comp xe lobes.
I attempted to edjumacate myself into cam durations logic, which thoroughly confused my but from what I've gathered from articles and Youtube; I was led to believe that adhering to the following specs would equate to better power:
-More lift would = more valve opening = more flow = more power
-If Intake/Exhaust varience % is lower than 80% than more exhaust durations are better in cam choice (some chevymag)
-More exhaust durations would equate to better velocity.
-Tighter LSA puts power lower in power band.
All this data crunching eventually gave me a headache and made me believe that throwing the 228/230 cam with less lift than what the 228r cam had equate to less power, but I decide to say **** it all and give up the 114lsa for 112lsa just so I can just enjoy a choppier idle for the summer time.
I succeeded in attaining the choppier idle; but I really did not expect to pick up an extra 20hp/10tq out of 2 extra exhaust durations and less lift
Can anyone help explain why?
Dyno comparison between cams:
I was pretty happy with the results, expected to hit 400hp, but ended up with 429hp/389tq, which made me happy... but of course, I "needed" more...
The need for more came before any funds were available for buying "more"; throwing more monies into my build to work out flaws was not an option. I did however have a slightly 'larger' cam lying in my garage.
The 228r cam that put me at 429hp was spec'ed at: 228/228 588/588 114lsa, the 228r cam uses the aggresive comp xer lobes. Power with this cam peaked at about 6100rpm
The rogue cam in my garage was reground by deltacams to 228/230 .571/.573 112lsa, and has the less aggresive comp xe lobes.
I attempted to edjumacate myself into cam durations logic, which thoroughly confused my but from what I've gathered from articles and Youtube; I was led to believe that adhering to the following specs would equate to better power:
-More lift would = more valve opening = more flow = more power
-If Intake/Exhaust varience % is lower than 80% than more exhaust durations are better in cam choice (some chevymag)
-More exhaust durations would equate to better velocity.
-Tighter LSA puts power lower in power band.
All this data crunching eventually gave me a headache and made me believe that throwing the 228/230 cam with less lift than what the 228r cam had equate to less power, but I decide to say **** it all and give up the 114lsa for 112lsa just so I can just enjoy a choppier idle for the summer time.
I succeeded in attaining the choppier idle; but I really did not expect to pick up an extra 20hp/10tq out of 2 extra exhaust durations and less lift
Can anyone help explain why?
Dyno comparison between cams:
