Cathedral vs Ls3 test
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From: over dere
While there are arguable differences in a few areas the article reinforces why I went with 235cc Thompson Motorsports heads on my LS2 11.5 comp all motor build. Life under 5k is much more important to me than a 6.5k and up numbers.
Originally Posted by 84FSP
While there are arguable differences in a few areas the article reinforces why I went with 235cc Thompson Motorsports heads on my LS2 11.5 comp all motor build. Life under 5k is much more important to me than a 6.5k and up numbers.
I've just never been impressed by them. I think people short the 243s and move on to easily myself. Ima fan of using production heads mostly. But i made 451whp with stock 243s and a stock cam.....so what to i know.
for a truck yea .....for a hotrod not at all. They don't call them tq ports for nuffin. Although i do appreciate good broad power i personally would never cam or h/c a ls for a hotrod and mind losing some low end (call it below 4k rpm) for the massive gain in topend power the ls3's offer. When it's all said and done with being able to pull more gear with the ls3 heads due to the rpm advantage there will be no real world low end loss.
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From: Central Cal.
I like this too. Because, where do you spend over 80% (and that's CONSERVATIVE) of your time on the street? UNDER 5000RPM. Why make that area of the rev band miserable to live with most of the time just to make it scream better over 5K?
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From: over dere
Why do you need an extra 10 ft\lbs of torque at 2500 rpm for idling around in a 3500 lb car? The extra power is actually more usable up top because you’re just not using it down low
[QUOTE=HioSSilver;19991406]well you can't ask me what's wrong with them and site what's wrong with them yourself .....lol.
I've just never been impressed by them. I think people short the 243s and move on to easily myself. Ima fan of using production heads mostly. But i made 451whp with stock 243s and a stock cam.....so what to i know.
Yah I mean the valve train is definitely an issue out of the box but a set of BTR springs and titanium retainers with turned down ls3 valves can change that.
I've just never been impressed by them. I think people short the 243s and move on to easily myself. Ima fan of using production heads mostly. But i made 451whp with stock 243s and a stock cam.....so what to i know.
Yah I mean the valve train is definitely an issue out of the box but a set of BTR springs and titanium retainers with turned down ls3 valves can change that.
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From: Central Cal.
ONLY 10ft/lbs? Usually more. When putting around town, a few extra #'s of torque always feels better than not having it.
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From: VA
If your modded car has less torque then it did stock, burn the piece of **** because you've severely fucked it up. That being said, I will take all the power up top the LS3 heads will give me! Cathedrals had there place in 1999 (lets party) now its 2018 and there is no reason to hold the LS back any longer.
I DIDN'T SEE ANYONE MENTION that both engines have different camshafts??????
“While not identical, the camshafts are very, very similar. Really, there were as many similarities as was possible.”
THIS TEST IS CRAP! Why?
we all know good and damn well two different engines will make different power. What about bearing clearances? Do you guys think that all the bearing clearances are exactly the same? No. What about friction in each motor? What about piston ring gaps? Piston ring seal? spark plugs? gap? Done on two different days also. I mean really? this is a bogus, waste of time test. We all know the LS3 heads are superior anyways....but just swap heads on the same motor in the same day to see the real difference. It could be less or even more. SMH
“While not identical, the camshafts are very, very similar. Really, there were as many similarities as was possible.”
THIS TEST IS CRAP! Why?
we all know good and damn well two different engines will make different power. What about bearing clearances? Do you guys think that all the bearing clearances are exactly the same? No. What about friction in each motor? What about piston ring gaps? Piston ring seal? spark plugs? gap? Done on two different days also. I mean really? this is a bogus, waste of time test. We all know the LS3 heads are superior anyways....but just swap heads on the same motor in the same day to see the real difference. It could be less or even more. SMH
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From: over dere
I DIDN'T SEE ANYONE MENTION that both engines have different camshafts??????
“While not identical, the camshafts are very, very similar. Really, there were as many similarities as was possible.”
THIS TEST IS CRAP! Why?
we all know good and damn well two different engines will make different power. What about bearing clearances? Do you guys think that all the bearing clearances are exactly the same? No. What about friction in each motor? What about piston ring gaps? Piston ring seal? spark plugs? gap? Done on two different days also. I mean really? this is a bogus, waste of time test. We all know the LS3 heads are superior anyways....but just swap heads on the same motor in the same day to see the real difference. It could be less or even more. SMH
“While not identical, the camshafts are very, very similar. Really, there were as many similarities as was possible.”
THIS TEST IS CRAP! Why?
we all know good and damn well two different engines will make different power. What about bearing clearances? Do you guys think that all the bearing clearances are exactly the same? No. What about friction in each motor? What about piston ring gaps? Piston ring seal? spark plugs? gap? Done on two different days also. I mean really? this is a bogus, waste of time test. We all know the LS3 heads are superior anyways....but just swap heads on the same motor in the same day to see the real difference. It could be less or even more. SMH
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From: Saskatchewan, Canada - where arguing "DA" is for the slow and weak...
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From: over dere