421 stroker?
TECH Enthusiast
Joined: May 2004
Posts: 549
Likes: 0
From: St. Peters, MO
I'll wait for Vendetta to chime in here, but I'm pretty sure Jason Short (a moderator on here) either builds them or knows where to get them. If I remember correctly, he had a 410ci LT1 built, sold the shortblock to another member on here, who sold it to my friend just up the street. I don't know the specs of hand but it is a 410ci.
BTW- You can make the same or more power on a 38X-39X with superior heads. A 421 would cost a lot, leave no room for a mistake, be prone to overheating, allow no n20, boost, power adders, oh yeah did I say expensive? Ballpark 9k+ for a forged shortblock.
BTW- You can make the same or more power on a 38X-39X with superior heads. A 421 would cost a lot, leave no room for a mistake, be prone to overheating, allow no n20, boost, power adders, oh yeah did I say expensive? Ballpark 9k+ for a forged shortblock.
Staging Lane
Joined: Apr 2004
Posts: 82
Likes: 0
From: Rockingham, NC
The stroke/rod combo would cause a great deal of side loading, and to get those cubes ud have to go .060 over. So with that being said, id expect you having to buildin a new engine ever15-20K mi(im being optimistic) 388 is the BEST size to do max effort with. plently of cyl wall for good ring seal and the stroke is short enough it wont be trying to push the piston out the side of the block with a 6in rod.
Matt
421 is "doable" but in my opinion not worth doing. I know a guy that built 2 421ci LTx motors for his car. Not cheap, but the parts were not the problem.....its the machine work. You are running on the edge with a build like that (clearances/wall thickness, etc..). I personally would not go larger than 410ci. You can build a 410 for no more than a 383/396 motor. Just be sure to use Lunati or Oliver rods since the big end is more profiled for clearing the pan rail. I wish now I would have kept the 410ci I sold 
Jason
Jason
Originally Posted by rockcamaro97
The stroke/rod combo would cause a great deal of side loading, and to get those cubes ud have to go .060 over.
Matt
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
TECH Senior Member
Joined: Jun 2003
Posts: 9,339
Likes: 3
From: NYC metro area
Haven't seen any 421ci LT1s in person, or even heard of many. I knew a guy who bought a 410ci LT1 to drop into a 97 Z28, but don't talk to him much and haven't heard from him since he bought it.
Jay, what was that shortblock in the garage that I saw while up there, that wasn't the 410ci was it?
Originally Posted by JasonShort
421 is "doable" but in my opinion not worth doing. I know a guy that built 2 421ci LTx motors for his car. Not cheap, but the parts were not the problem.....its the machine work. You are running on the edge with a build like that (clearances/wall thickness, etc..). I personally would not go larger than 410ci. You can build a 410 for no more than a 383/396 motor. Just be sure to use Lunati or Oliver rods since the big end is more profiled for clearing the pan rail. I wish now I would have kept the 410ci I sold
Jason
Jason
TECH Apprentice
Joined: Aug 2004
Posts: 362
Likes: 0
I really don't see the point. If it's only for saying "I have a 4XX ci motor" then more power to you but for me, it just isn't worth the enormous costs involved.
More power can be had out of a 2.2, Brodix, etc "exotic" head with a SR setup in a 355, 383 or 396 setup and would cost quite a bit less.
Personally I don't see why people dump a ton of money into these huge displacement LT1 setups. Hell if I wanted large displacement I would get rid of the LT1 block completely and go with an old SBC setup.
To me trying to push the LT1 block much further than it was ever meant to go is just putting money into something that won't have the longevity or cost of a much better platform.
More power can be had out of a 2.2, Brodix, etc "exotic" head with a SR setup in a 355, 383 or 396 setup and would cost quite a bit less.
Personally I don't see why people dump a ton of money into these huge displacement LT1 setups. Hell if I wanted large displacement I would get rid of the LT1 block completely and go with an old SBC setup.
To me trying to push the LT1 block much further than it was ever meant to go is just putting money into something that won't have the longevity or cost of a much better platform.
TECH Apprentice
Joined: Aug 2004
Posts: 362
Likes: 0
To add to that it seems like a good many people want all of this and that without thinking everything through. They don't realize the costs involved in all of the peripherals. $1500 fuel system setups. $3000+ in transmission and drivetrain setups. Suspension, engine management, the list is endless.
People see a $1500 budget stroker kit and forget about everything else that has to go along with it to make a setup that works.
I don't know how many pipe dreams I've seen or read. People with these grand ideas of making a 1000HP beast usually don't get past the basic bolt-ons. It takes more than pipe dreams and hopes....it takes time, dedication, research and most of all, money to put together a setup that works well together.
People see a $1500 budget stroker kit and forget about everything else that has to go along with it to make a setup that works.
I don't know how many pipe dreams I've seen or read. People with these grand ideas of making a 1000HP beast usually don't get past the basic bolt-ons. It takes more than pipe dreams and hopes....it takes time, dedication, research and most of all, money to put together a setup that works well together.
Thread Starter
Teching In
Joined: Mar 2005
Posts: 7
Likes: 0
?
Originally Posted by JasonShort
421 is "doable" but in my opinion not worth doing. I know a guy that built 2 421ci LTx motors for his car. Not cheap, but the parts were not the problem.....its the machine work. You are running on the edge with a build like that (clearances/wall thickness, etc..). I personally would not go larger than 410ci. You can build a 410 for no more than a 383/396 motor. Just be sure to use Lunati or Oliver rods since the big end is more profiled for clearing the pan rail. I wish now I would have kept the 410ci I sold
Jason
Jason
so how much power did you get out of your 410ci? the reason i've been thinkin bout a 421,is,i know a guy who had on,and he put down about 650-700rwhp, and that was the meanest sounding car i've ever heard (other than cars that make your ears bleed), to me, it's just cooler with all motor,rather than blower,or NOS
TECH Fanatic
Joined: Jun 2002
Posts: 1,124
Likes: 0
From: kuwait
Originally Posted by METALBEAST
My friend Jeff has a 421 LT1 in his 99 S10. It puts down well over 500 RWHP but the engine alone cost him $16,000.
JasonShort. i think you right man..
Anybody know who sells a good 410 stroker kit for the LT1??
I gotta ask this question, why would anyone build anything over a 396 inch LT1? Really anything over a 383 you have to worry about bottom end cracking into water if street driven. I put 1.5 inches of hardblock in my 383 just to be safe. A properly fed 383/396 will make 650 flywheel hp if you got the bank account to put the proper top end on it, fuel system and buy the cooling system to run it on the street. Is it to say" I gotta 421"? Because any cylinder head short of 330 cfm aint gonna begin to feed it over 5000 rpm, add that sheetmetal or HEAVILY modded converted Victor carb intake to feed those heads is gonna cost ya......so why even go down that road?
Just curious.
David
Just curious.
David
