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Discussion Starter #1 (Edited)
Hi im back. Thanks again to everyone the helped me with my door issue.
I have a 67 tempest,pontiac 400 out of a early 70's gto with 4x heads,th400 shift kit but no stall,Edelbrock proformer intake,holley 750,4.56 10 bolt,r. tires are n50 15's
Im looking to put a mild cam in it but i dont want to have to replace the springs or ect... If i have too i will. To gain the most out of the set up i have.
So any good choices? For what im running. My car will be an almost every day driver.
Im just trying to get a little more hp and lopey idle.

Thanks
Robert
 

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general motors part #9779068 is best for what your looking for. nice cam for any pontiac motor.
 

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Daily drive 4.56 gear car?? And you want more cam, like 7 MPG isn't low enough at $4 a gallon.. How fast is the car now, sounds like a bracket 1/8th mile setup beyond the stall. Did someone swap out the fast motor/trans? I would swap the rear to a 3.?? gear and have a cruiser. I hope the N50s arent' original 1980s units..
 

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Discussion Starter #4
cam specs

Thanks for the part number. I am trying to turn it into a 1/8 mile car. The n50 tires are just mock up tires. Im going to probably go with p275,p295 size tire. I live in the city so the set up doesnt bother me. Plus i like putting those little rice burner cars to shame. I run 110 octane in it so im paying 8 bucks already. I do have a stall for it but i think its too big. (4000) im not sure. I picked up the car set up this way. I put front disc conversion, qai coilovers on all four corners. But im married with kids and my pockets are getting thin. So that why im just looking to put just something that i can still use stock springs,push rods,ect.. i just cant afford head work right now.

But thanks for getting back to me!!!!!

Robert
 

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That's a ton of gear for a Pontiac, even in an eighth-mile car. That's also waaaaay too much converter (4000). The thing is going to be at red-line or above the instant you hit the throttle. Your torque peak is going to be down around 3500 rpm or less, but with the way it's set up you're going to be "wasting" it all because the motor's going to spend nearly all its time way above 3500. If you've also got stock cast rods in it, it's a time-bomb on wheels. You said you wanted a "mild" cam, but it sounds like the rest of the car is set up (or is going to be set up) exactly "wrong" for a mild cam. It's possible to build Pontiacs that are optimized for short gears and 7000+ rpm, but the starting point for an engine like that is a MANDATORY combination of good quality forged steel rods and also a good quality forged steel crank, and probably 4-bolt splayed main caps. It'll also take a lot "more" cam and significantly better heads.

Ram Air IV cars came standard with 3.90 gears, 4.30's were optional and were as low as it went - they also couldn't be had with a/c because of the rpm - and Ram Air IV had much better heads and more cam than what you're talking about building.

Don't want to necessarily rain on your parade here, but you'll be a lot happier (and your car will run a long stronger) if the rpm range the engine is built for is better matched to your rear gear ratio and torque converter setup.

Bear
 

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Discussion Starter #6
cam choice

Cool thanks for the info. That makes a big difference. This is all new to me with muscle cars and engines and rpm ranges,gears,ect... I am building an all forged 383 for it but its going to take awhile to finish it. So thats why im looking to do a little bit to the pontiac motor thats in it already. But i dont want to be driving a bomb waiting to go off either.
 

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Discussion Starter #8
Tell my boss to give me a raise so i can get a bulter proformance crate motor. Lol
Well thats why im here. All my friends are chevy,mopar guys. I wanted a pontiac though. Some of guys tell me that that 400 is a boat anchor. Go with a chevy motor. So thats what i started.
I have no problem dumpibg all that crap. I can probably get 1500.00 for the 383 parts. I would be willing to drop that in the 400 but i stiil want to drive the car this summer. The motor is basically stock and runs great So take the money and swap the gears first? Seems like the best place to start.
 

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Discussion Starter #10
Why YOU helped me with door issue. Let me know where i should start or where im fn up. I can take criticism. Im 40 and finally own a muscle car. And idk nothing about these motors. So i guess im looking for a starting point to achieve the motor i want. Im not looking to build a cruiser.
 

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Let me give you a reference.
Call Jim Lehart at Central Virginia Machine (434) 767 9915. I know of no one better to work with you and plan out a Pontiac build, starting with where you are and staying within your budget, that will be as strong as it's possible to be withing those constraints.

I was lucky enough to find and talk with him back when I was starting my build in 2009. He told me the truth, was very willing to share what he knew and make recommendations -- long before I ever decided to spend a nickel with him. He's the guy who actually wrote most of the "Building Your Shortblock" chapter in Jim Hand's book.

If you're serious about building a Pontiac, he's worthy of your trust.

Bear
 

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Discussion Starter #13
Thanks bear for explaing the pro and cons of what i have and what i want to do. Im going to swap the gears out and just finish my 383 build.

Thank
Robert
 

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I don't know what your true goal or intentions are but this is my first classic muscle car as well and have learned A TON about this car and cars in general just by researching this board/google and tinkering with the car. You don't have to spend gobs of money and go all out on having a super fast car. IF ANYTHING... and i stress this a ton.....

Get the car working right from top to bottom. At a minimum... a solid Pontiac 350 v8 with a tci streetfighter th350 tranny and saturday night special converter will give you a nice ride and be reasonable at the pump. I can light up the tires at the light and have a very nice "JUMP" at the line. All that can be done at a very cheap/reasonable budget.

If you want more power... move up to a 400 or 455 v8 and adjust tranny and converter accordingly. But make sure it's solid meaning no leaks.... Only after that and you can run the car 20,000k like that would I then start worrying about upgrading cam's etc.

Just my two cents... I might be ranting and preaching a little too much but I'm just super happy with all the work that I've put into my car over last 2 years and to be able to daily drive it with pride is cool.
 
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