bored lt1
03-30-2007, 11:42 PM
#1
Teching In
Thread Starter
Join Date: Nov 2006
Location: fort worth, tx
Posts: 25
Likes: 0
Received 0 Likes
on
0 Posts
bored lt1 well i am now getting my motor rebuilt and i was thinking of having it bored, but i was wondering how far to do it and if it really helps that much
03-31-2007, 09:04 AM
#3
12 Second Club
iTrader: (5)
Join Date: Jul 2006
Location: Tampa, Fl
Posts: 583
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by lt1camarojoe
well i am now getting my motor rebuilt and i was thinking of having it bored, but i was wondering how far to do it and if it really helps that much
Regarding your rebuild and selecting parts -- take a look at the book "Building Small Block Chevrolet Motors" by John Lingenfelter. It is a great read, and will help you quite a bit with selecting your bore/stroke combination as well as parts. It goes through the entire process from selecting a block and machining it all the way to cam selection and the small odds and ins that go with it.
03-31-2007, 09:43 AM
#4
Boring alone won't net much, installing forged/balanced components while you are
in there will allow you to sustain much higher power levels and RPM.
As mentioned above, the idea is to get a fresh surface.
You can also go with different pistons to raise or lower compression to match your application.
Here's some useful boring/stroking info I shamelessly ripped form another thread:
in there will allow you to sustain much higher power levels and RPM.
As mentioned above, the idea is to get a fresh surface.
You can also go with different pistons to raise or lower compression to match your application.
Here's some useful boring/stroking info I shamelessly ripped form another thread:
Originally Posted by OutlawZ
here's the skinny on LT1 buildups.... it all depends what you're looking for. there are quite a few non stroked NASTY LT1's out there in the 355 cubic inch variety as well so depending on your budget don't get super dedicated to having to stroke it....
355 ci LT1:
Bore: 4.030 (.030 overbore with an .030 oversize piston)
stroke: 3.50 (stock stroke)
rod length: 5.7", 5.85", 6"
notes: 355's don't get the additional torque of a stroker motor. upped compression for more power is almost a must. Also a 6" rod 355 has one of the best piston/rod ratio in the game. more dwell time at TDC, more complete burn will usually result in more power. Try to get compression up to about 11.5:1 to 11.75:1. Will still run on pump gas at those levels. Good heads/intake also a good idea... you can use the stock crank but I would at least 2 bolt stud the main caps while you're down there.... good quality h-beam rod as well for bottom end stability.
383 ci LT1:
Bore: 4.030 (same as above)
Stroke: 3.75"
Rods: usually 5.85 or 6"....
notes: 383's will get the added torque from the increased stroke. same deal with compression as a 355. Definitely get a good forged crank as well as rods and pistons. Lunati, SCAT, or Eagle at a minimum. Block clearancing is required for rod bolt clearance but it's pretty minor and any competent shop can do it....
396 ci LT1:
Bore 4.030 (same)
Stroke: 3.875"
Rods: i've only seen 5.85's
notes: again more torque from more cubes and more stroke. block requires alot of clearancing and be careful because you don't want engine man to cut into a water jacket reducing block to garbage. with custom work i think you could use a longer rod possibly but not advisable... i have limited experience with 396's.... i personally like the 383 route since you can always clearance more later if you want the 396 and 13 ci isn't a whole **** ton of an increase....
355 ci LT1:
Bore: 4.030 (.030 overbore with an .030 oversize piston)
stroke: 3.50 (stock stroke)
rod length: 5.7", 5.85", 6"
notes: 355's don't get the additional torque of a stroker motor. upped compression for more power is almost a must. Also a 6" rod 355 has one of the best piston/rod ratio in the game. more dwell time at TDC, more complete burn will usually result in more power. Try to get compression up to about 11.5:1 to 11.75:1. Will still run on pump gas at those levels. Good heads/intake also a good idea... you can use the stock crank but I would at least 2 bolt stud the main caps while you're down there.... good quality h-beam rod as well for bottom end stability.
383 ci LT1:
Bore: 4.030 (same as above)
Stroke: 3.75"
Rods: usually 5.85 or 6"....
notes: 383's will get the added torque from the increased stroke. same deal with compression as a 355. Definitely get a good forged crank as well as rods and pistons. Lunati, SCAT, or Eagle at a minimum. Block clearancing is required for rod bolt clearance but it's pretty minor and any competent shop can do it....
396 ci LT1:
Bore 4.030 (same)
Stroke: 3.875"
Rods: i've only seen 5.85's
notes: again more torque from more cubes and more stroke. block requires alot of clearancing and be careful because you don't want engine man to cut into a water jacket reducing block to garbage. with custom work i think you could use a longer rod possibly but not advisable... i have limited experience with 396's.... i personally like the 383 route since you can always clearance more later if you want the 396 and 13 ci isn't a whole **** ton of an increase....
04-01-2007, 10:47 AM
#6
Originally Posted by chromeplated500
I would push a 383...strokers are incredible...
Strokers done right can be great but I see more people thinking cubes are power and ending up with under performers. Most people can not afford to do a shortblock and topend both right at the same time. As such for most people I would recommend good heads and cam on the stock shortblock to hold you over for a couple years while you look at doing the stroker to put under those heads.
Biggest exception would be in the case of shortblock damage where it can make sense to throw a stroker shortblock under stock unported heads to get the car back together but you have to understand that in this case the car will be weak compared to a well done heads and cam setup.
Just to be clear my definition of the right heads is usually ported stockers, when I say stock heads I mean as cast, porting can do amazing things.
04-01-2007, 10:59 AM
#7
TECH Regular
iTrader: (1)
Join Date: Apr 2005
Location: Almont, MI
Posts: 445
Likes: 0
Received 0 Likes
on
0 Posts
LT1 castings can typically be opened up about .050" to .060". As stated above, this will not net you much as far as HP. It should atleast be rehoned during the rebuild. I also say look into a good heads/cam combo if looking for noticeable power gains. Keep in mind, the stock rotating assembly has its limits as far as how much power it will handle, so a forged rotating assembly may be necessary depending on how much power you would like to get out of the car.
