Welcome aboard Seagroves and thank you for having the common sense to seek help before you pull the trigger on this purchase. All of us on this board have been where you are and I'm sure that most of us would do things a little differently.......like asking for help.......if we had it all to do over again.

You'll likely get several different suggestions from different board members because we all think a little bit differently. Here's mine......

As far as the manual transmission and associated parts, that is going to be determined by whether or not you would rather have a manual than an automatic and also who the manufacturer of the transmission was. It could be a Saginaw or it could be a Muncie. The Saginaw was a weak-suck operation, intended to transfer power from a relatively low-horsepower motor. I would not use it in any application where more than 250-275 horsepower would be generated by the motor. It's actually torque that kills parts, but we will talk in terms of horsepower because that is what you will understand at this point in your schooling. I would also not use it if I were going to use some sticky tires on the rear. The first time you would rev the motor and dump the clutch and the tires would hook up, BAM....and you'd be running over the gears with the rear tires. The Muncie, on the other hand, will tolerate quite a lot of horsepower as it was used behind big blocks from the factory. Even if you didn't want to change from an auto to a stick, it might be worth it to you to go ahead and get the manual so you could offer it as an option to the person you will sell the car to eventually. Muncies are getting scarce and the ones that are out there for sale now are patched-together junk, pretty much. And don't say that you'll never sell the car, we all have sold cars that we thought would last for a lifetime of enjoyment for us, either because we came upon bad times or for some other reason.

So, there is the reasoning behind the transmission dilemma.

Now, let's address modifications to the car. Everyone begins hot rodding the vehicle at the wrong end. Mods should always begin at the rear of the car, with gears, positraction, upgrades to suspension, upgrades to shocks, etc., etc. The rear end components that are in the car now were designed at the factory for the engine's horsepower that was bolted into the engine bay. You stated that you believe the horsepower of the motor that is in the car is 175 hp. Be advised that the factory fitted the car with a rear differential and suspension system that will handle 175 hp and not a penny more. They are in the business of selling cars at a profit and could not make a profit if they bolted in a rear end system that would handle a 350 hp motor. See how that works?? So, along comes Seagroves with a complete motor upgrade to 350 hp and the first thing that happens is BAM.....and he's running over the differential parts that couldn't handle the additional power. See how that works??

First thing I would do is to identify exactly what the motor and transmission are in the car. There are two places to look on the motor to tell what it is and how it was outfitted at the factory. First is the block casting number, a raised 7 or 8 digit number on the bellhousing flange where the bellhousing bolts to the block, on the driver's side. This is a little hard to get to with the motor in the car and is usually obscured with grease and dirt, so you may have to use a toothbrush and some solvent such as kerosene to get in there and scrub the numbers so you can read them. A good strong flashlight and a telescoping mechanic's mirror will be worth their weight in gold also. Those cars were offered from the factory with a 305 also, so don't just assume that it is a 350. If it is a 305, you might want to begin looking around for a rebuildable 350 short block or long block and adjust your stepdad's asking price. These numbers that I'm going to help you with will tell the whole tale.....

Here's the casting number shown looking from the rear of the motor toward the front of the motor at the bellhousing flange location......
http://cdn.speednik.com/wp-content/b...asylum-com.jpg
Here is another photo showing the location of the casting number......
http://www.thecamaro.com/images/Part...N_Location.jpg

There is another set of alpha-numeric numbers on the block, at the very front of the motor on the ledge where the cylinder head ends. This location is very close to the top water pump bolt on the passenger side of the block and is stamped into the metal, rather than being cast in. It is on the machined deck of the cylinder block and will look something like this....
http://www.nastyz28.com/2gcog/blkvin.jpg
The second numbers/letters is the suffix number we will be interested in, the other one is a partial VIN number.....
http://www.crankshaftcoalition.com/w...c_block_id.jpg
These numbers are normally obscured by either an alternator or an AC compressor, so you wil likely have to remove some parts to see them.

The third numbers we will be interested in will be the cylinder head casting numbers. You will have to remove the valve covers to see them. Look at both heads, because sometimes they are different heads on the same stock motor.
http://cdn.speednik.com/wp-content/b...tockCastNo.jpg

I would very much enjoy coming along with you on this journey and I think I speak for the others on this board as well. Post back soon.

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