370 vs 390 vs 408
#1
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well my stock crank bent and took out a main bearing. (not 100% sure thats what happened but its my theroy)
im looking in to a dragonslayer crankshaft for the new engine. it will stay a 6.0 iron block. they sell the crank in 3.622, 3.8 and 4.0 my heads are tfs cnc 225s and my cam is a 235/239 and i have a proflo intake. the turbine i have now is a 98mm with .96 ar t6.
i do miss how quick the old 1.25 87mm t4 turbine spooled thats why i was thinking the 390 or 408.
out of the 3 if all the same parts were used would the smaller ci be stronger? more journal overlap on the crank. and im not sure about piston pin locations.
ive had the car for a few years now with many changes and ups and downs. the local track (10 minutes away) is closing but i do have 4 others all with in 2 hrs to go to. but i just want to drive the car as much as i can at this point, a solid 1050 whp is all im after. using a th400 i would assume 1200-1250 flywheel horsepower would be the target.
after some of the things that happened with aes im not sure if their 390 route is worth taking.
thoughts and ideas from everyone.
im looking in to a dragonslayer crankshaft for the new engine. it will stay a 6.0 iron block. they sell the crank in 3.622, 3.8 and 4.0 my heads are tfs cnc 225s and my cam is a 235/239 and i have a proflo intake. the turbine i have now is a 98mm with .96 ar t6.
i do miss how quick the old 1.25 87mm t4 turbine spooled thats why i was thinking the 390 or 408.
out of the 3 if all the same parts were used would the smaller ci be stronger? more journal overlap on the crank. and im not sure about piston pin locations.
ive had the car for a few years now with many changes and ups and downs. the local track (10 minutes away) is closing but i do have 4 others all with in 2 hrs to go to. but i just want to drive the car as much as i can at this point, a solid 1050 whp is all im after. using a th400 i would assume 1200-1250 flywheel horsepower would be the target.
after some of the things that happened with aes im not sure if their 390 route is worth taking.
thoughts and ideas from everyone.
#5
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Wouldnt it be better to go ahead and have the block bored since it could have caused damage?
If thats the case I'd have it bored .030 over and for the same price you can get the 4" crank and have the 408.
Id think with that turbo and the 408 you would hit your goal and then some...
If thats the case I'd have it bored .030 over and for the same price you can get the 4" crank and have the 408.
Id think with that turbo and the 408 you would hit your goal and then some...
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#9
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A shorter stroke results in a stronger crank, 408s have had issues with the pistons as well. The sleeves in factory LSx blocks aren't long enough to give the 4" crank proper geometry.
@chrs1313 - What do you mean? AES is still around.
@chrs1313 - What do you mean? AES is still around.
#11
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#14
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I think the waiting time is what everyone is talking about. Not that it's an issue if you plan your build. That and they aren't really active on here since Fraser, I guess the rest of the team is busy building engines lol.
Doesn't change the fact they build killer motors. I went with an AES 398.. More cubes than the 390 to try help my twin 72's, and more meat left in the engine than a 408.
Best of both worlds I think?
Doesn't change the fact they build killer motors. I went with an AES 398.. More cubes than the 390 to try help my twin 72's, and more meat left in the engine than a 408.
Best of both worlds I think?
#17
#18
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408"... No replacement for displacement... (more cubes will take more air flow, less restriction/less psi)..Not to mention more power off boost, better launches, quicker spooling (if turboed)
4" Callies compstar crank is easily good for 1100rwhp... Don't believe the BS...![Bomb](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_bomb.gif)
If the block is machined right and the piston to bore clearance is right, you will not have excessive piston rock or oil consumption. (although this does happen in cookie cutter/thrown together short blocks)..
There is a reason that most 1000+rwhp cars are over 402"...
4" Callies compstar crank is easily good for 1100rwhp... Don't believe the BS...
![Bomb](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_bomb.gif)
If the block is machined right and the piston to bore clearance is right, you will not have excessive piston rock or oil consumption. (although this does happen in cookie cutter/thrown together short blocks)..
There is a reason that most 1000+rwhp cars are over 402"...
#19
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408"... No replacement for displacement... (more cubes will take more air flow, less restriction/less psi)..Not to mention more power off boost, better launches, quicker spooling (if turboed)
4" Callies compstar crank is easily good for 1100rwhp... Don't believe the BS...![Bomb](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_bomb.gif)
If the block is machined right and the piston to bore clearance is right, you will not have excessive piston rock or oil consumption. (although this does happen in cookie cutter/thrown together short blocks)..
There is a reason that most 1000+rwhp cars are over 402"...
4" Callies compstar crank is easily good for 1100rwhp... Don't believe the BS...
![Bomb](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_bomb.gif)
If the block is machined right and the piston to bore clearance is right, you will not have excessive piston rock or oil consumption. (although this does happen in cookie cutter/thrown together short blocks)..
There is a reason that most 1000+rwhp cars are over 402"...
Yes if the motor is machined right it will not have oil consumption issues, but that's in the N/A world. We're talking about cramming boost down its throat and pushing the limits of the internals here.
By the way, there are alot of other 1000+rwhp cars that are not over 400 cu in......