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Thundrn_Lightning
Romans 10: 9-13
I've heard of a few going well over 20 pounds, but that is the exception. Mid teens seem to be pretty common. If you talk to Lidio I believe he will tell you 15-16# all day long on the stock Lightning shortblock.
Have fun,
Have fun,
gasguzzler
Grasshoppa'
10lbs. is probably max with a K/B before you have to start rocking timing pretty far. - Brian
thePUNISHER
Supporting Vendor
as lona as its intercooled you can push over 15#in with no troubles. the only peroblem is the stock head blots. they tend to stretch and lift. might be a wise choice to switch to arp. but as long as theres no detonation you can take it pretty far. and marcus, whats the difference in 15# boost between an s-trim and a novi? are you talking about discharge temp??
Guys, remember that boost is simply a measure of an engine's resistance to airflow. So, 15#s with good heads and cam may blow the internals right out of the block because the power level may be beyond what the stock components can handle, while 15# on stock heads and cam may be just fine.
The 15# limit is actually because of dynamic compression ratio and not an internal limit for the motor. That equates to around a 16:1 compression ratio and going beyond that even on race gas is tough because the heat of compression will tend to pre-ignite the mixture.
The stock internals can handle about 600 hp reliably. Above that it's just a matter of time before the connecting rods give up the ghost. You'll find people who have made more, and you'll find people who have made less and still poked a hole in a piston or bent a rod. So, that's a "round number."
The 15# limit is actually because of dynamic compression ratio and not an internal limit for the motor. That equates to around a 16:1 compression ratio and going beyond that even on race gas is tough because the heat of compression will tend to pre-ignite the mixture.
The stock internals can handle about 600 hp reliably. Above that it's just a matter of time before the connecting rods give up the ghost. You'll find people who have made more, and you'll find people who have made less and still poked a hole in a piston or bent a rod. So, that's a "round number."
Thundrn_Lightning
Romans 10: 9-13
Good points, guys.
I think there is a point where you have to get real serious ($$$) to go faster. I'd say that it is the 15# of boost (with an average S-Trim and heads/cam, for example), and probably in the mid/high 11s in race trim. Anything more than that will require major rotating assembly upgrades, among other things.
I think there is a point where you have to get real serious ($$$) to go faster. I'd say that it is the 15# of boost (with an average S-Trim and heads/cam, for example), and probably in the mid/high 11s in race trim. Anything more than that will require major rotating assembly upgrades, among other things.
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thePUNISHER
Supporting Vendor
hey marcus why would an s-trim not make as much power as a novi at 15 psi? given both engines are identical. is the reason because the discharge temp of the novi is cooler? i dont understand why this would be.
please explain the logic. thanks. paul delpo
please explain the logic. thanks. paul delpo
Paul, yes you'd have to look at what RPM (blower RPM) that S-trim is making 15lbs of boost. Past it's range and it is really heating the air.
You can also compare CFM ratings, like Jeff pointed out if you reduce the restriction on the output side of the blower boost will go down and you will reach a point that the compressor (blower) can't move enough air.
You can also compare CFM ratings, like Jeff pointed out if you reduce the restriction on the output side of the blower boost will go down and you will reach a point that the compressor (blower) can't move enough air.
LightningWX
Lightning tuning flunky
FMOS Racing said:
Hold on a second there. I vagely remeber you saying the connecting rods would handle 500hp right around when GJLS dynoed his truck. Am I off my rock or did you change your mind
.EDIT I'd also like to add
Boost: is a measure of pressure, pressure is a result of resistance. Alot of what boost you can run would depend on the engine set up and the compresser type and how much air it can flow. It's borderline unfair to ask this question as open as you have, very hard for the guys who can formulate an answer to be accurate.
Hey I'm just looking out for the thinking dudes, don't want to overheat there information compressor with alot of volume.
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Nope, ~600 hp (if I said 500 hp, then I was off my rocker). I mentioned to Jerry that he was walking on the knife's edge at his power level and detonation could be catastrophic. Thankfully when detonation came calling, his head gasket absorbed the punch. On my combo I had O-ringed heads and Loc-wires, so the connecting rod bent.
I made well over 500 hp on my combo for a couple of years before I finally screwed up. My engine croaked because I got greedy and made a mistake. But the engine was fine living at that power level - I was pretty impressed with the condition of the internals - excluding one piston and one connecting rod - when I pulled the motor down.
I made well over 500 hp on my combo for a couple of years before I finally screwed up. My engine croaked because I got greedy and made a mistake. But the engine was fine living at that power level - I was pretty impressed with the condition of the internals - excluding one piston and one connecting rod - when I pulled the motor down.
LightningWX
Lightning tuning flunky
So there is clout behind what I said in that one "to O-ring or not" thread. FYI I said something about head gaskets being a fuses for not blowing out rods or pistons.
Yep. Even with the forged internals, my current setup is not (and will not be) o-ringed.
