Rotating assy rec.
07-03-2019, 10:30 AM
#1
Rotating assy rec. I’m planning to buy a new rotating assembly, I have a new LS3 block, AFR 260 heads and all the rest. Was planning on a destroked engine first but have been rethinking. Going 4.00” stroke.
Any recommendations, Scat, Manley, Callies? They are pretty much the same price, any quality difference?
Any recommendations, Scat, Manley, Callies? They are pretty much the same price, any quality difference?
07-03-2019, 10:49 AM
#4
TECH Senior Member
07-03-2019, 11:50 AM
#5
07-03-2019, 02:41 PM
#7
I’m planning to buy a new rotating assembly, I have a new LS3 block, AFR 260 heads and all the rest. Was planning on a destroked engine first but have been rethinking. Going 4.00” stroke.
Any recommendations, Scat, Manley, Callies? They are pretty much the same price, any quality difference?
Any recommendations, Scat, Manley, Callies? They are pretty much the same price, any quality difference?
A destroker only makes sense to me if there is some compelling reason to keep displacement down. To take advantage of the shorter stroke (and longer rods it makes room for) you'll have to spin the engine faster, which will require an expensive fancy valvetrain arrangement. Overall, it tends to be pretty "racey", whereas a stroker turning 6500rpm will make great power, won't require anything fancy on the top end, and will likely be a more reliable "workhorse" for a long time.
That said, I do love the idea of a 4.8 (3.268" stroke) with a 4.065 bore (5.55L). Or better yet, a 4.125" bore (5.7L). All kinds of room for valves and airflow around them! But again, unless there's some kind of rule against the bigger displacement, there's really no good reason to give it up.
Edit to add:
If the engine is to live, piston speed MUST be kept at or below 25 meters/sec. This applies to all piston engines.
For reference, a 4" stroke LS7 @ 7000rpm has a piston speed of 23.7m/s. If you reduce stroke to 3.268, you'll need 8550rpm to hit that same 23.7m/s. A cup car engine (4.185x3.25) hits 25m/s @ 9200rpm...
Last edited by Hodgdon Extreme; 07-03-2019 at 02:53 PM.
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07-03-2019, 03:01 PM
#8
Sounds like you need to nail down what your actual goals are - that'll allow you to make good decisions on how to get there.
A destroker only makes sense to me if there is some compelling reason to keep displacement down. To take advantage of the shorter stroke (and longer rods it makes room for) you'll have to spin the engine faster, which will require an expensive fancy valvetrain arrangement. Overall, it tends to be pretty "racey", whereas a stroker turning 6500rpm will make great power and won't require anything fancy on the top end.
That said, I do love the idea of a 4.8 (3.268" stroke) with a 4.065 bore (5.55L). Or better yet, a 4.125" bore (5.7L). All kinds of room for valves and airflow around them! But again, unless there's some kind of rule against the bigger displacement, there's really no good reason to give it up.
A destroker only makes sense to me if there is some compelling reason to keep displacement down. To take advantage of the shorter stroke (and longer rods it makes room for) you'll have to spin the engine faster, which will require an expensive fancy valvetrain arrangement. Overall, it tends to be pretty "racey", whereas a stroker turning 6500rpm will make great power and won't require anything fancy on the top end.
That said, I do love the idea of a 4.8 (3.268" stroke) with a 4.065 bore (5.55L). Or better yet, a 4.125" bore (5.7L). All kinds of room for valves and airflow around them! But again, unless there's some kind of rule against the bigger displacement, there's really no good reason to give it up.
Instead of having the brand new block and AFR heads just laying around I thought I could use it for my other car but then I need another rotating assembly. So, if I should buy a new RA I might as well go with a 4.00” stroke.
That’s the reason behind it all, not that I can’t make up my mind.
07-03-2019, 04:47 PM
#10
07-03-2019, 05:03 PM
#11
I have had good success with Callies, Manley and stock parts. Molnar Performance I have heard great things about. Tom Molnar split off from K1 and is now on his own.
Highly recommend Mahle powerpak pistons. Because of the small ring pack you can run a 4" stroke crank and a long rod and still not have the wrist pin impinge on the oil ringland.
A stroked ls3 will be nice, especially with good heads. Run a Holley sniper or Fast 102 with short runners to limit torque, and make tons of high rpm power. Long runner intakes like stock LS3 and long runner fast intake will be all done by 6500, and won't give you the power curve you're looking for.
With the right parts a 4" stroke engine can have a similarly shaped power curve to a short stroke screamer.
https://ls1tech.com/forums/dynamomet...l#post20107577
Check out the power curve on this thing. That's 8000 rpm btw out of a 427.
Highly recommend Mahle powerpak pistons. Because of the small ring pack you can run a 4" stroke crank and a long rod and still not have the wrist pin impinge on the oil ringland.
A stroked ls3 will be nice, especially with good heads. Run a Holley sniper or Fast 102 with short runners to limit torque, and make tons of high rpm power. Long runner intakes like stock LS3 and long runner fast intake will be all done by 6500, and won't give you the power curve you're looking for.
With the right parts a 4" stroke engine can have a similarly shaped power curve to a short stroke screamer.
https://ls1tech.com/forums/dynamomet...l#post20107577
Check out the power curve on this thing. That's 8000 rpm btw out of a 427.
07-10-2019, 12:33 AM
#13
I have a Callies Magnum 3.27" stroke crank with Howards billet rods (used) if you are interested.... PM me.
Molnar has been my go to in 2017 and up to current for quality, good pricing, and not just blowing smoke up your *** with what their products can do. It helps to have the founder of the company (Tom Molnar) at the helm who also co-founded K1 (then left and founded Molnar) plus he was the engineer who made the Oliver Speedway rod
Molnar has been my go to in 2017 and up to current for quality, good pricing, and not just blowing smoke up your *** with what their products can do. It helps to have the founder of the company (Tom Molnar) at the helm who also co-founded K1 (then left and founded Molnar) plus he was the engineer who made the Oliver Speedway rod
07-10-2019, 01:12 PM
#14
3.9” is as far as you should go with a stock GM ls3 block, that is for a street driven car. More than 3.9” and you will have piston rock and wear the skirts out with high oil consumption and blow by as a result.
For all out race engine it doesn’t matter since they are overhauled quite often.
07-10-2019, 02:38 PM
#15
Did some more research and also called Molnar, K1 and Callies, they all say the same if you really question them.
3.9” is as far as you should go with a stock GM ls3 block, that is for a street driven car. More than 3.9” and you will have piston rock and wear the skirts out with high oil consumption and blow by as a result.
For all out race engine it doesn’t matter since they are overhauled quite often.
3.9” is as far as you should go with a stock GM ls3 block, that is for a street driven car. More than 3.9” and you will have piston rock and wear the skirts out with high oil consumption and blow by as a result.
For all out race engine it doesn’t matter since they are overhauled quite often.
Rock & oil burning nightmares are true if dealing with an engine assembler instead of an engine builder. There are a lit if bad shops that assembly vs build. Pick the wrong piston for a 4 inch stroke and you'll have a mess of oil consumption etc. However,Both Wiseco, Diamondand probably a few others have special taper pistons that move the ring package up. The trick piston with correct taper allows it to stay centered better with far less rock.
I have a LS1 383 w/4 inch stroke Callies crank / Wiseco pistons with 11,000 mikes burns less oil than a new stock LS1. The level on the dip stick barely moves over 3,000 miles. Checked at each gas fill.
Likewise have a 416 4 inch stroke Callies that burn oil like a stock LS1 (1/2 quart 2,000 miles) also Wiseco but built looser for harder performance use.
Builder said reasonable to expect 50,000 to 75,000 miles before refresh needed with normal daily driver use and some performance use. Beating on every day and every weekend tithe strip then expect less.
When new and stock my 99 TA wanted 1/2 quart every 1,500 to 2,000 miles
Personally, I'd be reluctant to go more than 4 inch stroke on a stock LS1/LS2/LS3 sleeve block if it was a daily driver.
Last edited by 99 Black Bird T/A; 07-10-2019 at 03:36 PM.
07-10-2019, 05:00 PM
#17
The taper on the other hand makes sence.
07-11-2019, 07:54 AM
#18
Did some more research and also called Molnar, K1 and Callies, they all say the same if you really question them.
3.9” is as far as you should go with a stock GM ls3 block, that is for a street driven car. More than 3.9” and you will have piston rock and wear the skirts out with high oil consumption and blow by as a result.
For all out race engine it doesn’t matter since they are overhauled quite often.
3.9” is as far as you should go with a stock GM ls3 block, that is for a street driven car. More than 3.9” and you will have piston rock and wear the skirts out with high oil consumption and blow by as a result.
For all out race engine it doesn’t matter since they are overhauled quite often.
07-11-2019, 08:26 AM
#19
Lots of street driven cars out there with 4” stroke cranks seem to say otherwise. You should see what actual piston manufacturers say. Summit posted a REALLY good explanation of how strokers work a little while back. I would suggest searching their posts and reading up on it.