LT1 - Max Bore/Stroke
Thread Starter
TECH Regular
Joined: Nov 2004
Posts: 415
Likes: 0
From: Reno, NV
LT1 - Max Bore/Stroke Hi Folks,
Have picked up an LT1 block to rebuild for the Impala SS. Thinking about a forged, solid-roller with moderate bore/stroke (a 377) and a 2-bar ProCharger, ported intake and heads with Jesel shafts to turn 6-6.5k.
Can the LT1 bore to 4.155? Was looking for the info with search; couldn't find the answer. Sorry if a repeat...
Have picked up an LT1 block to rebuild for the Impala SS. Thinking about a forged, solid-roller with moderate bore/stroke (a 377) and a 2-bar ProCharger, ported intake and heads with Jesel shafts to turn 6-6.5k.
Can the LT1 bore to 4.155? Was looking for the info with search; couldn't find the answer. Sorry if a repeat...
I believe a 409 was the biggest LT1 I have ever seen as far as displacement.... I forgot what the bore and stroke was but yeah it was like a 3.875" stroke and like a pretty large overbore... actually i think the stroke was bigger than 3.875 cause that combined with a .030 would give you a 396.... I don't think another .030 (.060 total) would give you another 13 cubic inches.....
But a 409 LT1 was the biggest i've heard in an impala... at that point you can't use it in most power adder setups cuz the cylinder walls are too think at that point.... the guy that did it was an NA Impala that ran pretty hard...
But a 409 LT1 was the biggest i've heard in an impala... at that point you can't use it in most power adder setups cuz the cylinder walls are too think at that point.... the guy that did it was an NA Impala that ran pretty hard...
I have a 410 ci LT1, def. the biggest you can go. But the torque should be nasty, The cylinder walls def. would be to thin at that point for sure, that's why i'm going the nitrous route. And the price it cost to build probably really doesn't justify it.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
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
Joined: Nov 2001
Posts: 10,023
Likes: 6
From: LT1 land...the "409" of the 90s!
Originally Posted by urbanhunter44
Yeah I've heard of 421s. Imo if you're stroking it just go with a 383 and be happy.
pretty much. getting a head to support extra cubes is a PITA
Take it .60 over and run her till she blows, get a great set of heads done by LE or AI. Let them know what your plans are and I bet you a dollar they can make it happen for you.
TECH Addict
Joined: Jul 2005
Posts: 2,153
Likes: 3
Originally Posted by MrBill97396
Take it .60 over and run her till she blows...
Mike
Originally Posted by engineermike
I'm .060" and running 20 psi boost. Gone 143 mph in the quarter at full weight + cage + turbo + intercooler = pig. Also had an overboost incident that severely blew both head gaskets and still no block problems. My guess is 25 - 30 psi, maybe more.
Mike
Mike
FormerVendor
Joined: Nov 2001
Posts: 3,065
Likes: 6
From: Houston, Tx.
A 4.000 inch crank will go in with the right parts and is a good NA engine but the pistons are somewhat short for a power adder. I am doing some 408 inch LT1s at 4.030 bore like that. I wouldn't go to a 4.060 initially but a lot of people do after several rebuilds or because they had to and they don't seem to have many problems. It also depends on what pistons are available on the shelf if you are trying to stay on a budget.
Thread Starter
TECH Regular
Joined: Nov 2004
Posts: 415
Likes: 0
From: Reno, NV
Thanks for all the feedback. Sounds like the max bore/stroke is 4.060 x 4.00. This comes out to 414.28 by my calculations.
I am going to go .030" over to start and stay with the stock crank. The other engine will get a 3.75" crank and .030 over to make a 383.
I am going to go .030" over to start and stay with the stock crank. The other engine will get a 3.75" crank and .030 over to make a 383.
Yeah I was gonna say the same thing..... 383 or 396 can cost you as little as like 4K if you get a budget stroker kit. If you go full blown with splayed mains and all the right parts then it'll run you about 15K....
I've got about 13K in my 383..... there wasn't any reason to go 396 so i didn't....
I've got about 13K in my 383..... there wasn't any reason to go 396 so i didn't....