455 CID LSX shortblock???
#41
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hey, it may not be practical but being an old time pontiac guy i think its a good question that you chevy guys just dont understand! i had a 74 GTO ,I dropped a 455 in because pontiac blocks were all the same size 350-400-455 . dont let these chevy guys give you a bad time about this ?
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Being a Pontiac guy at my roots (yea..it was a bit of a difficult thing to install the LS1 in place of my 400) I can understand the alure of having a "true" 455, but it really is kind of a moot point. Besides, PMD (Pontiac MOTOR Division) caps on an LSX powered car seems kinda funky, anyway.
#44
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Unless you heard this from some dude at a flea market selling old parts on a sheet, this is, once again proving that even engine builders/speed shops employ morons who don't know what the hell they're talkiing about.
#45
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And you're not one of them? He is right, the larger these ci motors get, the less you would want to put the into a "daily driver" because those cylinder walls ARE getting quite thin, and those long strokes (4.1 and above) don't coincide very well with long term reliability. The head gasket material is reduced between the bores, the piston compression heights are reduced weakening the piston, the longer strokes pulls the pistons further out of the bottom of the bore causing them to rock at the bottom of the stroke - effectively causing more wear on the skirts and possibly more oil consumption issues if the rings are pulled out of the hole at the bottom of that long stroke.
#46
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Without a taller deck block the 4.1 stroker has weaker pistons since the piston ring lands are higher & more. The engine builders don't recommend the 4.1 stroker for anyone using power adders like nitrous for that reason. I think without the taller deck
you want to not go over a 4.0 stroke unless you want to stay N/A. I was told this by a couple of posting engine builders since I am a nitrous guy.
you want to not go over a 4.0 stroke unless you want to stay N/A. I was told this by a couple of posting engine builders since I am a nitrous guy.
#47
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nope.
For a race engine it could be an issue, not for a steet car with street radials.
There's 5+ year old LS1 engines with 4.125 strokes still running just fine today in street cars. I know a few with almost 100,000 miles in a 42x+ci engines. Thats all "blah, blah, blah" talk. Run something like you explain above...HARD at the track every weekend and it won't last long, agreed. For the street, its just fine and will hold up fine.
For a race engine it could be an issue, not for a steet car with street radials.
He is right, the larger these ci motors get, the less you would want to put the into a "daily driver" because those cylinder walls ARE getting quite thin, and those long strokes (4.1 and above) don't coincide very well with long term reliability. The head gasket material is reduced between the bores, the piston compression heights are reduced weakening the piston, the longer strokes pulls the pistons further out of the bottom of the bore causing them to rock at the bottom of the stroke - effectively causing more wear on the skirts and possibly more oil consumption issues if the rings are pulled out of the hole at the bottom of that long stroke.
#48
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Without a taller deck block the 4.1 stroker has weaker pistons since the piston ring lands are higher & more. The engine builders don't recommend the 4.1 stroker for anyone using power adders like nitrous for that reason. I think without the taller deck
you want to not go over a 4.0 stroke unless you want to stay N/A. I was told this by a couple of posting engine builders since I am a nitrous guy.
you want to not go over a 4.0 stroke unless you want to stay N/A. I was told this by a couple of posting engine builders since I am a nitrous guy.
#49
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We're pricing out the LSX 455s right now for a customer. I'd be more than happy to quote you a 455 if your interested shoot me a pm!
Jason
Jason
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Jason
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2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
#50
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And you're not one of them? He is right, the larger these ci motors get, the less you would want to put the into a "daily driver" because those cylinder walls ARE getting quite thin, and those long strokes (4.1 and above) don't coincide very well with long term reliability. The head gasket material is reduced between the bores, the piston compression heights are reduced weakening the piston, the longer strokes pulls the pistons further out of the bottom of the bore causing them to rock at the bottom of the stroke - effectively causing more wear on the skirts and possibly more oil consumption issues if the rings are pulled out of the hole at the bottom of that long stroke.
There are 200+K Ford 5.4 Mod Motor V8s that have 4.165 inch stroke motors in them from the factory with no problems. They even put Superchargers on them from the factory and still they run fine. It's all in the engineering and who specs the parts. You can mess it up for sure though as you say but if you know what you are doing you can run a lot more stroke than you think. I have done 455s with basically stock cylinder walls in the 4.125-4.135 range with no problems.
#53
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As mentioned before the nostaligia options include 389, 400, 428 and 455 Pontiacs. All good choices. 455 being the most expensive. Don't forget the other titles such as Tri-Power, Ram Air, Judge and Super Duty.
For me it would be a Ram Air 400 with the ram being provided by a compressor either in the form of a turbo or the brand new high efficiency 4 rotors Eaton SC from the LS9.
For me it would be a Ram Air 400 with the ram being provided by a compressor either in the form of a turbo or the brand new high efficiency 4 rotors Eaton SC from the LS9.
#54
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ohhh seriously? i have to disagree man. 455 has a slight torque advantage but the difference in HP is a lot greater.. have to give it to the LS6
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I was thinking about calling my 402 (if I ever get it) a 400.
Does MTI sell a short block 455? I didn't see it on the website.
And now (ls series) aren't even Chevy engines (346ci), they are G.M. engines. To think that Chevy, Buick or GMC get their own engines is nuts. The only brand to get exclusive engines is Caddy and they trickle down after a while. I think Saab even uses ecotec blocks for their engines. Oh and don't forget Honda engines in Saturns.
#56
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There are 200+K Ford 5.4 Mod Motor V8s that have 4.165 inch stroke motors in them from the factory with no problems. They even put Superchargers on them from the factory and still they run fine. It's all in the engineering and who specs the parts. You can mess it up for sure though as you say but if you know what you are doing you can run a lot more stroke than you think. I have done 455s with basically stock cylinder walls in the 4.125-4.135 range with no problems.
#58
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i didnt read this whole thing, so i might be making an *** of myself
1st i get why you want that last cid. Im an olds guys i hate the "oh a 455 is the same as a 454" bull ****. anyways Lenos toronado was a 455 so im sure they can do it....
1st i get why you want that last cid. Im an olds guys i hate the "oh a 455 is the same as a 454" bull ****. anyways Lenos toronado was a 455 so im sure they can do it....