Beginner help with engine choice and build

Hello I am new to the forums and older Pontiac in general so I want to apologize in advance for the very basic questions I am going to ask. I own a 2005 Pontiac gto and my dad lives and breaths Pontiac, well at least until family cars replaced fast ones.

I have become more and more interested in older Pontiacs and im looking to learn how to do more than bolt on stuff so id like to build a true Pontiac motor, with his help of course.

Im in the process of moving so it was bad timing but a gto went up for sale around here and really got my dad thinking. I don't think I would have the funds right now to restore a 66 gto like he had because everything around here it CT that old rusted out or costs an arm and a leg but I have come across a few different motors and some late 70 trans ams.

To get to the point id like to build a motor with Tri power and make a true poncho powered car but there's a lot of different routes.

I like big cubed engines but I hear the bigger blocks are weaker because of thinner walls and some years are 2 bolt main, 2 bolt main but drilled and tapped for 4 bolt and some were just 4 bolt out of the paackage. I've heard good things about a 400 stroker. The first car is looking like its going to be a 1978-81 trans am. I can get a trans am with a 400 but how does it compare to a 428 or 455 Pros and cons. To give an idea id like to be at 600-700 HP and i know those year trans ams are known for popping the t tops when putting real power to the pavement so i'm aware of the need extra frame support and bracing. Thank you for any information. A modern kit with internals would be amazing if anyone knows of a place that sells them or has links to a build thread where i can learn more. Its easier to read paper than the computer screen for me but my magazines should be coming in a few weeks    

Well, to start with, the late 70's 400 blocks are less than desireable for performance builds except for the W72 200/220hp versions which got better blocks. The 75-77 180hp blocks are generally weaker and not suited to a stroker build. Butler's Performance is a well known and respected Pontiac engine shop and supplier. They sell complete balanced rotating assemblies, ported aluminum heads and just about anything you need to meet your goals.
That brings us to the next point, your goals. It's not uncommon for us to hear new builders say they want 600-700hp, that seems to be the general "buzz word" these days, reinforced by the "hotrod" magazines and Hollywood. Don't kid yourself, 10 second daily driven street cars are NOT the norm! A true 400hp Pontiac V8 in a 3800lb traditional RWD Pontiac will be a very fun ride that will gather plenty of respect. Tripower is nice, but you'll be way ahead in power with the right 4 barrel carb and intake setup and the right heads/cam. 600-700hp is also very expensive, what kind of budget are you looking at?
Steve  
A little help... 'cause we don't all have to learn the hard way!

Thank you ill have to look them up. My 2005 gto has 400 hp and 400lb of torque and i would definitely like to have more than that... Budget wise, i'm selling my 05 gto so id probably put a limit of 25k on this build including the car though. I should be able to get the car where I want for 7000 but we can round it to 10k and have 15000 into the drive train maybe a little more. Reliability is big for me though so id rather spend a little extra and be safe instead of sorry. It wont be a daily driver so it doesn't have to drive like one.  

Welcome to the forum!
The following is just my 2 cents.. For what it's worth..
That kind of HP will cost plenty.. My motor was 12K and it's right @ 700HP at 7K RPM. Pure Pontiacs were always torque motors. You may want to think torque as much if not more than HP. The two are not always connected.
Just to give you an idea of what it might take to get to your numbers;
You'll need some CR so Pontiac iron heads are not the best for that on todays sorry excuse for gasoline, unless you want to run a mix of racing fuel w/pump gas to get your octane up. There are several good aluminum heads out there that will fill the bill.

Then there's the intake matched/ported to the heads. I'm not sure if any aftermarket intake will get you there with out some serious porting. Then finding a carb to breath at the higher RPM levels.
The camshaft- Bigger camshafts will raise the RPM range that HP/Torque come into play. "smaller" torque type camshafts operate in the lower ranges and will give you almost as much, if not as much, torque. Add lifters and springs to that.
Then there's the rods/pistons-Good aftermarket forged rods (I prefer H beam style) and forged pistons. Your factory crank will need some work (stress relieving, shot peened- etc..etc..) to take that kind of HP and torque, or buy one of the forged cranks that are available, then it all needs to be balanced w/flywheel, vibration damper and clutch if it's a manual.
Your block will need machine work and there's severeal options there as far as decking the block, etc. You'll also want lifter gallery support as Pontiac didn't have the beefiest lifter gallery support cast in.
Then there's the exhaust- Good headers and @ least a 2 1/2" diamter system.
Once you start piling on the HP/torque, you've got to look at the rest of the drive train, flywheel, transmission (not many out there take that kind of HP/Torque right off the shelf), drive line and rear end.


There's another blog stream on here called "dawna's build, tribute to heaven" that will give you some good direction on a good solid build.  
Jim,

My71:
Welcome to the forum!
The following is just my 2 cents.. For what it's worth..
That kind of HP will cost plenty.. My motor was 12K and it's right @ 700HP at 7K RPM. Pure Pontiacs were always torque motors. You may want to think torque as much if not more than HP. The two are not always connected.
Just to give you an idea of what it might take to get to your numbers;
You'll need some CR so Pontiac iron heads are not the best for that on todays sorry excuse for gasoline, unless you want to run a mix of racing fuel w/pump gas to get your octane up. There are several good aluminum heads out there that will fill the bill.

Then there's the intake matched/ported to the heads. I'm not sure if any aftermarket intake will get you there with out some serious porting. Then finding a carb to breath at the higher RPM levels.
The camshaft- Bigger camshafts will raise the RPM range that HP/Torque come into play. "smaller" torque type camshafts operate in the lower ranges and will give you almost as much, if not as much, torque. Add lifters and springs to that.
Then there's the rods/pistons-Good aftermarket forged rods (I prefer H beam style) and forged pistons. Your factory crank will need some work (stress relieving, shot peened- etc..etc..) to take that kind of HP and torque, or buy one of the forged cranks that are available, then it all needs to be balanced w/flywheel, vibration damper and clutch if it's a manual.
Your block will need machine work and there's severeal options there as far as decking the block, etc. You'll also want lifter gallery support as Pontiac didn't have the beefiest lifter gallery support cast in.
Then there's the exhaust- Good headers and @ least a 2 1/2" diamter system.
Once you start piling on the HP/torque, you've got to look at the rest of the drive train, flywheel, transmission (not many out there take that kind of HP/Torque right off the shelf), drive line and rear end.


There's another blog stream on here called "dawna's build, tribute to heaven" that will give you some good direction on a good solid build.

Thank you glad to be a part of the group and hopefully contributing more than just questions soon. I'll definitely pull up that thread this weekend when i get some free time and hopefully begin pricing everything out to get an idea and then work from there. I have been noticing torque being higher than horsepower on a the few dyno sheets i saw which i like. I'm also a diesel truck guy as well. I gave the hp numbers hoping to get a ballpark. Id rather have the internals over built so there's room to grow than under-built. My target is around 600hp with torque being higher.
I'm definitely looking to go manual have any transmissions proven better or is my best bet to have the stock one built if possible. I've only driven a couple of stick cars so this is a generalization but my brother has a 1990 300zx Twin Turbo and it seems like I cant even feel it shifting as well as a Subaru STI I sat in. I have a Tremec 6 speed in my car and some people say the transmission in general is notchy because of the resistance when shifting. I prefer the feeling of actually putting the car in gear and I was reading somewhere that older trannies where like that as well. Is this correct?

This forum has so much information its hard to get started so Thank you for you guidance. What kind of car is that 700HP engine in ?  

Some people like tremec transmissions, some don't.. All personal choice. Richmond gear is making the old Borgwarner T-10 series (including super T-10) but I don't think they market them to handle over 500 ft lbs of torque. They do have a 5 speed they say will handle 600HP I believe. I hear the T-56 is a stout manual trans also.
My motor started out life as a 428 HO and now sits in the red GTO shown in my avatar.  
Jim,