Ls2 408 stroker
But I do agree those 11/32 will be fine
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Haha. I'm not worried.
I was just curious about the stiffness difference between the series 300 and 500.
Although, I am curious to see what happens when these Manton pushrods arrive and get installed.
I'm expecting they should not only restore the lost power but also make more too and rev cleaner and higher.
I was just curious about the stiffness difference between the series 300 and 500.
Although, I am curious to see what happens when these Manton pushrods arrive and get installed.
I'm expecting they should not only restore the lost power but also make more too and rev cleaner and higher.
Originally Posted by bortous
Haha. I'm not worried.
I was just curious about the stiffness difference between the series 300 and 500.
Although, I am curious to see what happens when these Manton pushrods arrive and get installed.
I'm expecting they should not only restore the lost power but also make more too and rev cleaner and higher.
I was just curious about the stiffness difference between the series 300 and 500.
Although, I am curious to see what happens when these Manton pushrods arrive and get installed.
I'm expecting they should not only restore the lost power but also make more too and rev cleaner and higher.
Majoring in the minor and minoring in the major.
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Thread Starter
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Another update.
Those Manton pushrods were finally installed today.
All fitted with no clearance issues.
Engine is going on the dyno sometime today to see how things are.
Hopefully all good this time but we shall see.
Those Manton pushrods were finally installed today.
All fitted with no clearance issues.
Engine is going on the dyno sometime today to see how things are.
Hopefully all good this time but we shall see.
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Thread Starter
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Another update:
I am very pissed off once again.
Those Manton puhsrods did not do **** to the power output or improve high rpm potential.
Everything is exactly as it was before with those trend 5/16 pushrods.
Darth, primaries got checked when this first happened and they are all good. No issues there.
As mentioned before, the crow cam I have in there was never designed for a 1:8.1 ratio.
So now I have three options.
Option 1: Lighten valvetrain, go back to standard ratio ultra light rockers and lighter springs and see how current camshaft goes....
Option 2: Keep valvetrain but upgrade camshaft to a LLSR from Cam motion (which may suit it better) with less lift
Option 3: Go back to a cam motion camshaft with less lift to suit current combination
It's all a massive pain in the ***.
After all this, I am thinking that crow cam is just not as stable as the cam motion camshaft I had in there previously.
And making less power clearly indicates something is wrong.
Just spoke with Patrick Guerra too.
He dislikes those yella terra pro street rockers too as they are heavy and being a higher ratio would add to valvetrain instability even further.
He believes if I got back to the stock GM 1.7 or the YT 1.71 Ultra lite pros, the issue will most likely be resolved and it would make more power too.
But I am concerned with the open pressure of the pac 1209x spring at 500lb.
The YT are rated to 480lb max open pressure.
I also cannot fit GM rockers due to the larger 10mm threads.
So my only option is the YT.
I should have listened to my tuner in the first place.
Keep the same 1.7 rockers rockers, change spring to a 1207X and no problems.
It's driving me crazy.....
I am very pissed off once again.
Those Manton puhsrods did not do **** to the power output or improve high rpm potential.
Everything is exactly as it was before with those trend 5/16 pushrods.
Darth, primaries got checked when this first happened and they are all good. No issues there.
As mentioned before, the crow cam I have in there was never designed for a 1:8.1 ratio.
So now I have three options.
Option 1: Lighten valvetrain, go back to standard ratio ultra light rockers and lighter springs and see how current camshaft goes....
Option 2: Keep valvetrain but upgrade camshaft to a LLSR from Cam motion (which may suit it better) with less lift
Option 3: Go back to a cam motion camshaft with less lift to suit current combination
It's all a massive pain in the ***.
After all this, I am thinking that crow cam is just not as stable as the cam motion camshaft I had in there previously.
And making less power clearly indicates something is wrong.
Just spoke with Patrick Guerra too.
He dislikes those yella terra pro street rockers too as they are heavy and being a higher ratio would add to valvetrain instability even further.
He believes if I got back to the stock GM 1.7 or the YT 1.71 Ultra lite pros, the issue will most likely be resolved and it would make more power too.
But I am concerned with the open pressure of the pac 1209x spring at 500lb.
The YT are rated to 480lb max open pressure.
I also cannot fit GM rockers due to the larger 10mm threads.
So my only option is the YT.
I should have listened to my tuner in the first place.
Keep the same 1.7 rockers rockers, change spring to a 1207X and no problems.
It's driving me crazy.....
I think a cam change is likely going to be your cheapest option.
Sorry you're still not seeing the results you want. For what its worth, the manton pushrods were a good move.
You coulddd also...sell your top end complete and start fresh with some different heads, 1.7 rockers and 1207x springs and probably wouldn't be out too much in the long run.
The combo you have is probably better suited for someone with a solid roller and a heavy spring.
Sorry you're still not seeing the results you want. For what its worth, the manton pushrods were a good move.
You coulddd also...sell your top end complete and start fresh with some different heads, 1.7 rockers and 1207x springs and probably wouldn't be out too much in the long run.
The combo you have is probably better suited for someone with a solid roller and a heavy spring.
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Hi, Ive just read thru your thread, nice build. My old engine was ls2 454ci 239/254 hyd roller , ported ls3 heads 2.180 intake with fast lsxr long runners and it had 560rwhp. On the same dyno my mate just had his ls3 408 stroker , ported heads with a 236/248 cam and oem intake make 480rwhp . The highest a 408 has made on that same dyno has been 518rwhp So if your getting 500rwhp i think your somewhere in the ball park.
I think the reading you got from your previous engine was on a very generous dyno also, are you on the same dyno with new engine ? Has it been calibrated since you had the previous engine run up ? Dyno's are variable, drive it and see how your butt dyno goes
I think the reading you got from your previous engine was on a very generous dyno also, are you on the same dyno with new engine ? Has it been calibrated since you had the previous engine run up ? Dyno's are variable, drive it and see how your butt dyno goes
Hi, Ive just read thru your thread, nice build. My old engine was ls2 454ci 239/254 hyd roller , ported ls3 heads 2.180 intake with fast lsxr long runners and it had 560rwhp. On the same dyno my mate just had his ls3 408 stroker , ported heads with a 236/248 cam and oem intake make 480rwhp . The highest a 408 has made on that same dyno has been 518rwhp So if your getting 500rwhp i think your somewhere in the ball park.
I think the reading you got from your previous engine was on a very generous dyno also, are you on the same dyno with new engine ? Has it been calibrated since you had the previous engine run up ? Dyno's are variable, drive it and see how your butt dyno goes
I think the reading you got from your previous engine was on a very generous dyno also, are you on the same dyno with new engine ? Has it been calibrated since you had the previous engine run up ? Dyno's are variable, drive it and see how your butt dyno goes
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Joined: Sep 2014
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From: Mississippi
Hi, Ive just read thru your thread, nice build. My old engine was ls2 454ci 239/254 hyd roller , ported ls3 heads 2.180 intake with fast lsxr long runners and it had 560rwhp. On the same dyno my mate just had his ls3 408 stroker , ported heads with a 236/248 cam and oem intake make 480rwhp . The highest a 408 has made on that same dyno has been 518rwhp So if your getting 500rwhp i think your somewhere in the ball park.
I think the reading you got from your previous engine was on a very generous dyno also, are you on the same dyno with new engine ? Has it been calibrated since you had the previous engine run up ? Dyno's are variable, drive it and see how your butt dyno goes
I think the reading you got from your previous engine was on a very generous dyno also, are you on the same dyno with new engine ? Has it been calibrated since you had the previous engine run up ? Dyno's are variable, drive it and see how your butt dyno goes
What type of dyno ? Sound like a mustang dyno....
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From: Melbourne, Australia