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Discussion Starter · #1 ·
There are alot of posts on how to make more power, but what about refinement?
I have been sitting on a 350 because I don't know what to do with it. What should one invest in to get good power (300hp/tq +or-) and keep a smooth responsive engine?

Note: My block is a 2 bolt main, Mid 70's, and is gonna need work...
 

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Discussion Starter · #5 ·
No, but arn't the blocks the same just different intake, cam, pistons, and heads? With the exception of 4 bolt mains in some cases.
 

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Discussion Starter · #7 ·
mmmmm.... yeah scratch that last comment I guess the Gen 1 and Gen 2 blocks are quite different, I thought they were the same. Apparently just the mounts and bell housing remained the same.
So.... I guess I am looking for an actual LT1 block.....
If I would have found that web page a month ago would have saved some cash, more importantly if I would have found it afew hours ago would have saved myself some embarrassment....

http://www.wordiq.com/definition/GM_LT_engine
 

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.......more importantly if I would have found it afew hours ago would have saved myself some embarrassment.......
Pffft :rolleyes: !

Don't worry about that :) .......if you knew all you needed to know, you wouldn't have to come here! We've all been in pretty much that same boat at some point.

OK.....now that we know pretty much what you want out of the engine, what kind of car is this engine going in to?

What are the associated mods that this engine will be working with (full drive train info/full rear info/full exhaust info/projected vehicle weight)????? Also.....you gonna run computer controlled FI......or a carb?

This info is critical if we're to give you quality advice!

Also.....be advised that these engines with a mild performance cam will run great with 10.5:1 to 11:1 compression ratio......so don't get too 'exited' when we tell you to deck the block in order to raise the CR up into that range.

KW
 

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Sorry didn't see this direct question,
My goal is to have something that is fun without sacrificing comfort, pleasure, and practicality... (Basically smooth and quiet when I'm not in the mood for fun and games.)
He wants what I want, "Old Fashioned Power".

Like when you could order a Chev w/ 307/350/396/454 or Ford 302/ 351 2V/ 351 4v/ 428.

Each step up got you more HP and TORQUE. No sacrafices in NVH, easy starting, reliability, good AC, etc.
 

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Well lets not get too crazy in saying that an LT1 is so vastly different from a SBC. Making power for both is pretty much the same, if anything SBC may have an edge due to more cylinder head choices out there but there isn't too much of a difference. Compression ratio can be higher on an LT1 due to reverse cooling which does help a little though.

The important thing to realize is that LT1's have sequential fuel injection. IMO this is where the real benefit comes in as to 'refining' the motor and getting very street friendly power. However, with a good aftermarket fuel injection system on a gen 1 SBC you can get just as good results as any LT1 could.


So if you are starting with a mid 70's SBC block...my first bit of advice to you for building a fast motor that has the refined feel of a luxury car is to find a good fuel injection system and work from there.


If this is going in an LT1 car that already HAS an LT1, then scrap the old block and keep the LT1.

Old school ways of making power really haven't changed all that much...but technology is what really allows these old school power making tools to be utilized while still maintaining streetability. Builders could build you a 500hp SBC 20 years ago with no problem but modern technology is what is allowing 500hp motors to be put in factory cars that drive like a luxury vehicle when not romping on it. Fuel injection is a wonderful thing. Utilize it. The ability to run higher compression from things like reverse cooling and better combustion chamber design is a wonderful thing. Utilize it. Great flowing heads with great port velocity is a wonderful thing...not having to use a big overlap cam to make big power. Utilize it.

Try to build an old school SBC with some crappy heads, 9.0 compression and a carb and you'll make less power and have a less refined feeling motor than an LT1 with some good heads, 10.5 compression and fuel injection.
 

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Builders could build you a 500hp SBC 20 years ago with no problem but modern technology is what is allowing 500hp motors to be put in factory cars that drive like a luxury vehicle when not romping on it. Fuel injection is a wonderful thing. Utilize it.
That and having a ECM system monitoring everything helps too. :)
 

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Discussion Starter · #13 · (Edited)
Pffft :rolleyes: !

Don't worry about that :) .......if you knew all you needed to know, you wouldn't have to come here! We've all been in pretty much that same boat at some point.

OK.....now that we know pretty much what you want out of the engine, what kind of car is this engine going in to?

What are the associated mods that this engine will be working with (full drive train info/full rear info/full exhaust info/projected vehicle weight)????? Also.....you gonna run computer controlled FI......or a carb?

This info is critical if we're to give you quality advice!

Also.....be advised that these engines with a mild performance cam will run great with 10.5:1 to 11:1 compression ratio......so don't get too 'exited' when we tell you to deck the block in order to raise the CR up into that range.

KW
I am currently waiting to hear back on a 95 Caprice. I haven't spent any money on the engine yet but from what I am reading the LT1 is gonna be a better start.
I was thinking a simple TBI setup for the fuel delivery and a higher compression as oppose to Super Charging/Turbo.
I am looking at Sedans, I really like the B-Bodies but if this doesn’t pan out might go for an F-Body, but I would rather a B-Body because I like full size vehicles.
 

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......I am currently waiting to hear back on a 95 Caprice...........I was thinking a simple TBI setup for the fuel delivery.......
OK......STOP!

If you get a '95 Caprice, that car will already have the sequential fuel injection (SFI), which is way superior to TBI! I strongly recommend sticking with the SFI.

Now.....the Caprice came with two engine options; the L99 which is a 4.3L V8 and the LT1.

If the car you get has a L99, you may need to get a wire harness from a LT1 car (don't know this for sure.....).

The PCM will have to be recalibrated for the LT1.....it may have to be recalibrated even if it came with the LT1 depending on how much you mod the new engine (heads/cam).

My strongest recommendations......try to get a LT1 powered B-body and keep the SFI.

And.....I'd get the B-body FIRST and have the engine in it checked out.....because you may/should be able to upgrade the engine already in the car vs going out a buying another engine.

KW
 

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OK......STOP!
Kevin put it succinctly!

Before you go any further get the VIN # and someone can do a check on what the car came with from the factory.
 

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Discussion Starter · #17 · (Edited)
Gah... forgot about them having the 4.3L, I assumed it was a 350. I might be able to get down today and have a look over the car now that the 5 days of rain is over.

Good advice...
Especially where the car was a project that got ditched because he got something Ford. If I get down today I will grab the VIN.
Where do you go to check the VIN a GM dealer or can you do it online?

I was looking at an LT1 repower kit from Edelbrock 2900$, I would deffinatly need that job at the planning commission before I could afford to blow that kind of quid. My cousin suggested to go with a Vortec repower kit because its considerably cheaper. Can you even put Vortec parts on an LT1 block if you use Vortec heads and intake? I know the Vortec intakes have a different polt pattern then other intakes.
Hummm.... think I am getting ahead of myself here, don't have the car yet and talking pricy repower kits, but I feel I am getting close....
 

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Where do you go to check the VIN a GM dealer or can you do it online?

Hummm.... think I am getting ahead of myself here, don't have the car yet and talking pricy repower kits, but I feel I am getting close....

Shhhh its a secret. I hacked into GMs mainframe....whoops....dammit.


Get the VIN then we'll see WTf is under the hood and other vital statistics.

THEN we can get to the upping the power options.
 

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Discussion Starter · #19 ·
Shhhh its a secret. I hacked into GMs mainframe....whoops....dammit.


Get the VIN then we'll see WTf is under the hood and other vital statistics.

THEN we can get to the upping the power options.
lol,
Will post VIN as soon as I get it.
 
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