AI 355/383 Rotating Assemblies..
#1
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AI 355/383 Rotating Assemblies..
Anyone have any of these rotating assemblies from them?
Do you guys think its worth the money for those kits or you can purchase an assembly for less price and almost the same kit somewhere else?
Do you guys think its worth the money for those kits or you can purchase an assembly for less price and almost the same kit somewhere else?
#2
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They are building my crate engine now. I think the kits are well worth the money. You are paying for thier experience and expertise when you buy from them. Why piece something together that "might" work well when you can do some one stop shopping. Call and speak to them.
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i know they are a good shop but their prices are kind of high. And i wouldnt say the "pieced together" shortblocks people build arent putting out good results. Plently of budget builds run 10's, but not by people who have no clue how to build motors. So depending on your knowledge, mechanical ability, and various other things you pick up along the way is what should determine who builds you motor.
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definitely good kits with good prices.. they aren't that bad. a good crank is easy a grand.... so 2000 for the forged crank is a good deal.
if you want the 355 do their budget kit and keep your stock crank. you'll be fine up to 150-200 hp worth of spray on top of what the motor will put out...
but if you're wanting to do a forged crank
if you want the 355 do their budget kit and keep your stock crank. you'll be fine up to 150-200 hp worth of spray on top of what the motor will put out...
but if you're wanting to do a forged crank
#7
Compstar makes some nice stuff.
AI's prices seem on par with most of the other dealers.
http://www.compstarcomponents.com/dealers.htm#
AI's prices seem on par with most of the other dealers.
http://www.compstarcomponents.com/dealers.htm#
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Another note to keep in mind is that the compstar rotating assembly is already balanced.
Any of the eagle and scat rotating assemblies will have to be balanced (and THOROUGHLY checked for machining error).
I would make sure to check ANY brands machine work, but would have a lot more faith in the Compstar stuff to be correct.
Any of the eagle and scat rotating assemblies will have to be balanced (and THOROUGHLY checked for machining error).
I would make sure to check ANY brands machine work, but would have a lot more faith in the Compstar stuff to be correct.
Last edited by mpe331lx; 11-15-2008 at 02:20 AM. Reason: Spelling FTL
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Another note to keep in mind is that the compssar rotating assembly is already balanced.
Any of the eagle and scat rotating assemblies will have to be balanced (and THOROUGHLY checked for machining error).
I would make sure to check ANY brands machine work, but would have a lot more faith in the Compstar stuff to be correct.
Any of the eagle and scat rotating assemblies will have to be balanced (and THOROUGHLY checked for machining error).
I would make sure to check ANY brands machine work, but would have a lot more faith in the Compstar stuff to be correct.
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Any kits for the LT1 should be internally balanced (You can use any 86 and up one piece rear main seal rotating assembly).
People have used older two piece rear main seal kits with an adapter, but they are prone to leaking. That would be the only case where you got an externally balsnced kit, and I bet you'd have a hard time finding a balancer the is externally balanced for an LT1.
#11
Not sure I trust any mass-produced part as "balanced" without checking it.
I ordered my Eagle set "unbalanced" (saving about $200) and have it balanced at a local shop so that
I was sure it was TRUELY balanced to match my specific setup.
I paid $125 for the balance work, they removed a small amount of material from the forged crank.
Had it been severely out of balance, we would have had to have used Mallory at ~$100/slug.
I agree with mpe331lx, you want it internally balanced and use a neutral flywheel/flexplate.
It will make your life so much easier in the long run. If you ever had to replace it, you'd
have to know exactly what weight needs to be added/removed and where.
(I learned this the hard way when I bought a freshly rebuilt forged 355 )
Remember that a stock crank is externally balanced at the rear using a weighted flywheel/flexplate.
When you build a performance motor, you should really be installing an aftermarket neutral one anyhow
(in my case, picking up an SFI-approved flexplate was part of that goal)
I ordered my Eagle set "unbalanced" (saving about $200) and have it balanced at a local shop so that
I was sure it was TRUELY balanced to match my specific setup.
I paid $125 for the balance work, they removed a small amount of material from the forged crank.
Had it been severely out of balance, we would have had to have used Mallory at ~$100/slug.
I agree with mpe331lx, you want it internally balanced and use a neutral flywheel/flexplate.
It will make your life so much easier in the long run. If you ever had to replace it, you'd
have to know exactly what weight needs to be added/removed and where.
(I learned this the hard way when I bought a freshly rebuilt forged 355 )
Remember that a stock crank is externally balanced at the rear using a weighted flywheel/flexplate.
When you build a performance motor, you should really be installing an aftermarket neutral one anyhow
(in my case, picking up an SFI-approved flexplate was part of that goal)
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And what kind of rpm limit could this go to? 7000 max?
a solid roller big heads shaft rocker combo can be spun safely to 8K or beyond depending on how much intake/head you have to flow that much air....
I spin my motor to 7400 and shift.... makes peak power at 7300ish....
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RPM is not so much of a rotating assy question as it is an airflow and valvetrain issue.... generally your heads/cam/valvetrain will determine what you can make power and safely spin your motor to...... hydraulic roller combo's with stud mounted rockers i most likely wouldn't take past 6800...... probably would float the valves at any RPM beyond that...
a solid roller big heads shaft rocker combo can be spun safely to 8K or beyond depending on how much intake/head you have to flow that much air....
I spin my motor to 7400 and shift.... makes peak power at 7300ish....
a solid roller big heads shaft rocker combo can be spun safely to 8K or beyond depending on how much intake/head you have to flow that much air....
I spin my motor to 7400 and shift.... makes peak power at 7300ish....
The top end with determin how high your motor can spin, regardless of strength.
By RPM limit, I am pretty sure that he was asking about how high could it be spun without fear of a bottom end failure.
#16
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Bottom end failure would be a function of the machining tolerances, oiling, rod bolts and power. The kits they sell are used in Aleks' 355 which he spins to 8k without issue.
A well machined stock crank, forged rods and pistons shouldn't have a problem with 8k if WELL machined. Attention to detail is important and a well done stock crank 355 will last longer at high RPM than a fully built monster with issues.
Compstar parts are the nicest of the "cheap" parts. They are kind of in between the basement Eagle/Scat but below a Lunati/Callies high end versions. Like any part, you get what you pay for in most cases and saving money is more a function of choosing the right part for your setup than anything.
You might be able to save a couple of hundred by piecing together a bottom end with blemished EBAY eagle parts etc, but Ai sells good quality matched parts. I have heard horror stories (and had similar issue with my own part) of some Eagle cranks requiring hundreds of dollars in ballancing.
A well machined stock crank, forged rods and pistons shouldn't have a problem with 8k if WELL machined. Attention to detail is important and a well done stock crank 355 will last longer at high RPM than a fully built monster with issues.
Compstar parts are the nicest of the "cheap" parts. They are kind of in between the basement Eagle/Scat but below a Lunati/Callies high end versions. Like any part, you get what you pay for in most cases and saving money is more a function of choosing the right part for your setup than anything.
You might be able to save a couple of hundred by piecing together a bottom end with blemished EBAY eagle parts etc, but Ai sells good quality matched parts. I have heard horror stories (and had similar issue with my own part) of some Eagle cranks requiring hundreds of dollars in ballancing.
#17
Correct, and thank for the info tireburnin. I'm having my short block built by a local respected circle track engine builder so I should be good. Any tolerance tips specific to the LT1 engines, that I could pass to the, GEN1 sbc engine builder? Actually, tips that could be placed here for the thread topic not to be about me and my build only. thanks
#18
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Biggest problem you will face with a gen 1 builder doing an LT1 is getting him to accept the compression we run on pump gas. Most are horrified to hear about plans to run 11.5+ compression because they do not understand what the cooling and electronics let us get away with. Otherwise it is pretty much just another smallblock.
#19
Correct, and thank for the info tireburnin. I'm having my short block built by a local respected circle track engine builder so I should be good. Any tolerance tips specific to the LT1 engines, that I could pass to the, GEN1 sbc engine builder? Actually, tips that could be placed here for the thread topic not to be about me and my build only. thanks