Performance build and original drivetrain

[Cmuller0420]

Hey guys,

I’ve been contemplating doing a medium performance build and looking to do a stroker kit on a 360.

Being that the car has its original drivetrain - should I look for a second engine to build up as a performance motor? What have you done?

This will be my first build and wanting to do a build over the winter.

As a side note - can anyone recommend any good threads on building up a 360? I spent time going through the performance section on the forum, but not much for posts for the 360 motor. Would like to build something around 400-450hp or so if possible. Can the stock manual transmission handle that amount of power?

 

[moparleo]

What exactly do you have ? Year/model ? 3 or 4-speed ? Differential ? Or a fender tag would be great.

 

[Cmuller0420]

74 ralleye with 360 4 speed...not sure on the diff - here is the fender tag pic

 

[DrEamer]

Personally I would just build another engine, and store the original. Even though 1974 is not the most sought after, you can only have the engine original once. Blow it up, and it's gone forever. Plus, you can always drive the stocker if you do not get done with the project over the winter. As far as horsepower, 400 to 450 can be done with a 360 without a stroker. A stroker will make more torque, so you need to decide what driving characteristics you want. Either combination will blow the tires off at will if built right. Your transmission should be okey at the that level of horsepower.

 

[RJHJR]

I agree with DrEamer.
Set aside the original block and trany properly. Thrash the new ones.
My 4 speed was rebuilt by Brewer's Performance. Great job, reasonably priced.

 

[413]

What an awesome car. Look at the colors and options! You’d be crazy to hot rod that thing! Go get a 318 car and build a hot rod, or Better yet go buy a late model challenger that does everything well.

 

[Cmuller0420]

If I kept the original drivetrain in - what is a decent route for a reliable and somewhat increased performance? Or does one do a complete stock rebuild?

 

[413]

Increase compression ratio
Lower ratio rear end gears
bigger camshaft.

But not too big on the camshaft so you have low vacuum for power brakes, and it sounds rumpity rumpity like a 1/4 mile racecar. With too big a camshaft you give away low end power, you don’t want that on a street driven manual transmission car.

 

[Cmuller0420]

Increase compression ratio
Lower ratio rear end gears
bigger camshaft.

But not too big on the camshaft so you have low vacuum for power brakes, and it sounds rumpity rumpity like a 1/4 mile racecar. With too big a camshaft you give away low end power, you don’t want that on a street driven manual transmission car.

Doing those things - what is a rough idea of the end result performance wise?

 

[DrEamer]

Doing those things - what is a rough idea of the end result performance wise?

There are a lot of variables, but a program like Comp Cams CamQuest is fun to play with, and gives you a general idea. It's free, so nothing to lose. The most important thing as with any program, is to input the most accurate information for the best results. The nice thing is you can put in your intended use, and it will give different cam options.

 

[Cmuller0420]

For increasing compression ratio - I’m assuming different pistons and new heads or rework on the original ones would be the best way to accomplish that?

 

[aussiemark]

Personally I would just build another engine, and store the original. Even though 1974 is not the most sought after, you can only have the engine original once. Blow it up, and it's gone forever. Plus, you can always drive the stocker if you do not get done with the project over the winter. As far as horsepower, 400 to 450 can be done with a 360 without a stroker. A stroker will make more torque, so you need to decide what driving characteristics you want. Either combination will blow the tires off at will if built right. Your transmission should be okey at the that level of horsepower.

These are wise words if you do the original engine you will throw away a lot of parts it makes sense to start with another engine or if you are doing a stroker just get a good std bore 360 block and build it up with all new parts. Stroker will need better heads anyway so a block would be a better and cheaper starting point and leave the matching numbers engine alone remove the rocker shafts to take the tension off the valve springs and close all the valves to stop anything entering the cylinders and put it in a dry safe place.