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Discussion Starter #1
So I read a bunch of threads about the power differences between the two cam styles but not anything about with boost, I got a 433bbc solid roller e85 F1R blow thru-, cam specs .756/.737 264/270 113LSA, made 1032hp on on an engine dyno at 15.5lbs at 6500, so there's more power left in it when I actually spinning it to 7k (belt issues, now cogged). This gonna be on the street 80-90% of the time, I have 2000miles on this setup and I ate a crane cam ultra pro lifter, and a couple more were ready to go out, cam lobe and had bunch of cracked k-motion k-1000h springs (825lbs open), it's costing me an engine tear down a cleaning, new parts etc etc. obviously not the ideal street setup, but the repairs are pricy on this solid roller stuff, was considering stepping up to the cheapest jesel lifters ($1500) and different spring (k-motion out of business?) and giving it all another go around, but low-rpm street driving with my spring pressures could eat up the best lifter up...

So the option was put in front of me of going solid flat tappet, way cheaper parts, better street manners, but there is gonna be a power loss, just wanna know what boost does on a SFT vs a SR cam profile (around the same specs), is the power loss more drastic on a boosted setup vs an N/A setup? Any comparable setups out there?
 

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Sounds like way to much valve spring and lift and a little to much duration. My 12 year old Comp cam with about 35,000 miles on my 1004 hp. SBC-400 with a 248/260,114cl,592/610,210# on seat Idles at 750.Gets 12 MPG...Oldhead
 

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Definitely cam is on big side. K motion should be open I just got springs from them in august. Had similiar problems with k1000h breaking sent them in and they exchanged the brocken ones no problem free of charge. This was five years and 100 runs later. Good service to me.
 

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Discussion Starter #5
Thanx for te responses, they are brodix race rites 270cc ovals, 9:1cr
 

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I would rather have mild roller cam than solid lifter for power and reliability any day.lot of guys have cam/ lifter probs because they let them idle to low rpm wise.jmo
 

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With a flat tappet, use edm lifters. No problems idling here at .650 lift for long periods of time...15-20 minutes at a stint. Very aggressive ramps too.

And...no exploded roller lifters when you take them 'too far' or something goes wrong!

EVERY one of my pals with rollers, sooner or later, grenades the damn things. NO EXCEPTION!!!

Sadly, most of them caused catastrophic engine failure. Big $$$$.

If you don't need the 50 or 100 or whatever HP, do a nice breakin with flats and they will serve you well. 30 yera of watching this and from what I've seen, constant maintenance and $$$ are needed with rollers. JMO!
 
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