408 or 427 LSX block questions.
09-03-2007, 01:41 PM
#1
408 or 427 LSX block questions. I want to go bigger forged motor. Its between 408 and 427. 408 would be 6.0 block ,427 would be LSX block. LSX block is like another 1000 more than 6.0 block. But for some reason a few of the places selling the LSX 427 with it looks like same internals as the 408 ..callies crank, compstar rods and not sure piston make want like 3000 more for the LSX 427.
Are the crank and rods and pistons that much more for the LSX block?
Is the labor that much more extensive or difficult?
I am thinking just buy a callies speedpac and get the motor assembled locally.
But can't find a supplier selling these speed pacs for the LSX block yet. Can anyone pm me with a supplier and/or prices.
The 408 looks like a perfect motor size and seen lots of very fast cars running it. Only real reasons to go up to 427 is a bit more torque off boost, possibly faster spool up and just the coolness of having a 427 in my ta.
But 3000 bucks more sounds way too miuch.
Also think the APS twins will still do ok on the 427. Aps seems to think so. For sure they would do fine on a 408. I am not into max possible power but want to see 850rwhp potential with my gt7 cam and some afr 225 and my fast intake and nw 90 tb. With alc injection of course or e85 not on pure pump gas.
Am I being stupid here?. Is the 408 plenty for what I am trying to do. What difference in torque off boost and on boost between 408 and 427. Will the 427 rev slower? I was going to go 6.0 427 but hear the walls get too thin. Thats why figured the LSX block woudl be better idea if do go that big on displacement.
Are the crank and rods and pistons that much more for the LSX block?
Is the labor that much more extensive or difficult?
I am thinking just buy a callies speedpac and get the motor assembled locally.
But can't find a supplier selling these speed pacs for the LSX block yet. Can anyone pm me with a supplier and/or prices.
The 408 looks like a perfect motor size and seen lots of very fast cars running it. Only real reasons to go up to 427 is a bit more torque off boost, possibly faster spool up and just the coolness of having a 427 in my ta.
But 3000 bucks more sounds way too miuch.
Also think the APS twins will still do ok on the 427. Aps seems to think so. For sure they would do fine on a 408. I am not into max possible power but want to see 850rwhp potential with my gt7 cam and some afr 225 and my fast intake and nw 90 tb. With alc injection of course or e85 not on pure pump gas.
Am I being stupid here?. Is the 408 plenty for what I am trying to do. What difference in torque off boost and on boost between 408 and 427. Will the 427 rev slower? I was going to go 6.0 427 but hear the walls get too thin. Thats why figured the LSX block woudl be better idea if do go that big on displacement.
09-03-2007, 02:29 PM
#2
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I'm seeing about $2000 difference in the two setups you mentioned and the LSX block is about $1200 more than a 6.0 block. There could also be additional machining done on the LSx block, not sure what the additional costs are.
I think a 408 would be a good choice for you since your using an APS system and will most likely max it out at 850whp anyway.
Dab
I think a 408 would be a good choice for you since your using an APS system and will most likely max it out at 850whp anyway.
Dab
