bigchevy4x

Ive got a few questions about small block buildups and i hope you guys have some answers. Basically im trying to do what everyone else is....build the most power for the least amount of dough. Ive built a few 70's and 80's smallblocks but nothing newer and thats what most of the questions revolve around so feel free to chime in if you guys have any answers.....

what years are the Gen 1, 2, 3 Engines? And What changes were made? And what do the Lt and Ls designations stand for?

next is how do the vortech blocks compare to the older style? Can you put vortech heads on an older block?

What are the pre vortech motors?

Im also trying to figure out what years the intake bolts changed. I know the older motors were all at the same angle then the four center bolts were changed to straight up and down and then they went to four bolts on each side right?

I am planning on running these motors on a pre smog carb truck So i need the adapter manifolds. I know that you can oblong the intake bolt holes or get a diffrent manifold but do anyone make an adapter manifold to go to the 4 bolt on each side style?

I have been my engine kits from Northern auto parts and i have been pretty happy with them but i was currious why the later model kits are like 600 bucks for a master kit and the 69 to 80 blocks are like 3oo. Thats why i was thinking of building up an older block and putting vortech heads on it. I also noticed that they dont sell kits for motors newer then 2000.

Anthor question I had was what you guys thought about a vortech motor with a bigger cam and better pistons with like a roots type blower compared to dumping alot of money into building a motor without a blower. How would they compare roughly power wise and money wise?

Does anyone have a list of casting numbers for newer blocks?

Im also looking into building a 383. ive seen kits with pistons and a crank for like 700 bucks but that seems pretty cheap. How much maching goes into the buildup. I know th block has to be notched but is there anything else out of the ordinary?

Someone told me that if you change the cam to diffrent cam then you have to change the valve springs also.

I think the way to go is with a big block but i dont have any right now but i do have a few vortech motors and older blocks laying around to play with.

I really enjoyed building the motors that i have built and i want to build more just for the experince. I dont have alot of money but i like doing everything myself. I allready have decent motors in both my blazers im just trying to learn more. So thanks for any information and feel free to add anything intesting. Thanks
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BigBoom360ci

Well, from what I know theresa difference in car blocks and trucks blocks. Truck castings being heavier and cars being lighter. 70s truck blocks tended to come in 4bolts main setups. The car castings came with 2 bolt mains unless they were a early 70s late 60s high performance mill. Today guys are buying the small block 2 bolt main blocks and having them machined for 4 bolt aftermarket mains going in at an angle and farther into reduce stress and raise the RPM capability. As for the different generations The one thing i have noticed is the castings have less squaresh shape and all extra cast iron or aluminum is taken off reducing the weight. As for Vortech all I can think of is a factory performance intake system really kinda like the Turbo jet 396s n such..

tawd77

Ok, the head bolt change happened around 1986 - Pre 86 had 12 bolts holding the intake on, all at the same angle. around 85-86 the valve cover bolts were changed from perimeter to center, and the middle two intake bolts were put at more of an upright angle. The blocks were also changed to a 1 piece rear main seal at this time.

They basically had no other changes til the vortec came along in 1996. Then the intake only had 8 bolts total mounting it to the heads.

The vortec heads will fit just fine on an older style block. The only problem is, you need to use a vortec intake unless you want to have the heads redrilled to allow the older 12bolt intake to fit. The vortec heads are very limited on the amount of lift a cam can have. So it is usually necessary to have the heads machined before they are used in high performance applications.

a 383 is a cheap way to increase power/torque. The only thing that is different about the machine work involved with building a 383,is clearancing the block, and making sure there is clearance between the rods and the cam lobes.