Thread: 454 or502

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I gotta agree with RS, plenty of powerglides made it to the strip.

But, have you ever driven one through town?
Dam annoying.

Originally Posted by rspears

I'm not saying that it's the right choice for a build, but the old powerglide can indeed be built to handle the horsepower and torque. Here's just one of many articles pointing out the specifics of building one for rugged service - Powerglide Transmission Build - Building a Two-Speed Trans for Our '95 Camaro Drag Car - GM High-Tech Performance Magazine A quote from the article tagged here,

Yup, agree with that 100%. BUT! The OP is under the assumption he can just bolt a 600 HP BBC in front of that stock 6 cyl. PG and go racing... THAT is not going to happen. AND if he wants something that is "drivable on the street" he needs to go OD for livable RPM's...
Mark

Originally Posted by astroracer

Yup, agree with that 100%. BUT! The OP is under the assumption he can just bolt a 600 HP BBC in front of that stock 6 cyl. PG and go racing... THAT is not going to happen. AND if he wants something that is "drivable on the street" he needs to go OD for livable RPM's...
Mark

Yup, and I agree with that 100%. I think the key here is that Ken (OP) said in Post #9 that,

Originally Posted by Ken1960

I guess I want my cake and eat it too.

Ken, Mark's advice in Post #10 is 100% on target. To change from your anemic 6 to any V8 you need to start from scratch and build a platform, knowing what engine you're going to use. New brakes, new suspension (minimum new springs, bushings, ball joints), new drive shaft for starters, then also consider that your wiring is going to be 50 years old in another year. Bringing your Chevelle to a modern day, reliable cruiser pulled around by 600+HP is not going to be a cheap project, especially if you start taking it to a shop for someone else to do the work. Thing is, a '67 Chevelle is one sweet ride, when done right. You need to sit back, make a realistic plan, budget the plan, and then go for it focused on the end.

Well IIRC the 396 was an option in 1967?

I think he should take a little time going to some car shows and talk to the people with them-about ride and handling/braking-----and maybe look at making a clone with a 427-454 and add a 5 speed od or 700r4 along with 12 bolt rear( or a ford 9)-stay carb and low pressure fuel system--
advantages are that the aftermarket has mounts and headers--

Detroit Speed is a source for everything he needs for chassis-brakes,steering,suspension,etc look it up I can't get it to copy

Originally Posted by astroracer

AND if he wants something that is "drivable on the street" he needs to go OD for livable RPM's...
Mark

And if he goes OD, he'll need to go easy on the cam. All grinds have a "cruise rpm range" where the motor gets "up on the cam" and begins to be efficient. The motor will be inefficient under that range and you will have wasted money on an OD trans. Again, it's the combination of parts that you have to pay attention to.

Bottom line: Overdrive trans needs stock or very close to stock cam for the motor to be efficient in the cruise rpm range dictated by the OD trans. I got into an argument with a know-it-all on another forum who was convinced that his 300 degree cam (255 @0.050") was well-suited for use with his 700R4.

.

Ken1960 I hope you'll hang with us and keep the dialog going from your side. This has the potential of being a great thread for a lot of guys looking to convert a muscle car into an updated cruiser/street machine.

Is this another low budget (under $5000) build thread? Good rule of thumb is to
build a box the size of a big block and fill it with cash ($20 dollar bills). That is a
good start.

Originally Posted by techinspector1

Bottom line: Overdrive trans needs stock or very close to stock cam for the motor to be efficient in the cruise rpm range dictated by the OD trans. I got into an argument with a know-it-all on another forum who was convinced that his 300 degree cam (255 @0.050") was well-suited for use with his 700R4. .

Tech, I have been over this many times and you have nailed it, any performance cam will raise your powerband ( ideal rpm range) over a stock cam, and will be totally ineffecient at 1800-2000 rpms at highway speeds that a OD can add unless you throw in a gear change. I actually saw a guy put a 700r4 behind a mildly built motor and loose fuel mileage! He dropped his rpms down around 1800 and had to step on the gas anytime he went up a slight hill since his powerband had been raised with the performance grind. This is the same reason my blown duel carb'd 32 actually gets pretty decent fuel mileage (I have achieved 16 mpg) turning 2900-3000 rpms at 70 mph with my foot out of it but all bets are off when both carbs are wide open.

Well I didn't think it would be all that bad I know you guys know , car is in great condition I thought adding another 200 lbs on the front end wasn't that much for it . And I know I would have to change raidiator. and put a 12 bolt in with the lockers in it , the frame should handle the torgue . I thought them old powerglides was tough , it changes good I was going to put a stall drive in it , question. Is a powerglides built different in the 6 cly. Cars than the v -8 cars. I thought some of these cars came out with a bob and powerglides. I appreciate the advice

Ken,
Here's a link to the options that were available for the '67 Chevelle - FACTS FOR 1967 CHEVELLES, Al McKenzie As you say, the Powerglide was an option with the 396, but that was a pretty mild BBC, not the 600HP you're thinking about. If you're set on keeping the Powerglide 2-spd you'd be well advised to have it built for the power you plan to put through it. A better choice for driveability would be a TH-400 or 700R4 if you pay attention to the torque curve on your engine. The frame is not a problem, but your brakes & springs may be.

How do you plan to use the car? That's the key to your plan.

Ken, I don't think your 200 lbs of weight is much of the issue (heavier springs), its the extra 350 hp thats gonna make a difference. I just restored a SS Chevelle about 6 yrs ago, the SS had heavier sway bars (front & rear) boxed trailing arms and a 12 bolt rear end (on the suspension & frame), I almost forgot the SS also had disc front brakes, stopping a big block with drums is harder to do as well and with that much hp probably not wise. None of the above was offered on the 6 cyl cars so I would think those parts would need definetly upgraded, keep in mind the LS6 was a bad boy no question but still was not 650 hp + a shot of nitrous! Have fun, do 'er right once and you won't regret it, these guys will keep you straight.

If you use alum heads and manifold, water pump,etc you will not add nearly as much weight

Differances between differant power level trans are number of disc/plates, planet gears, shaft sizes and I think the 6 cyl pg back then was air cooled

I might be wanting to much , I'm going to drive car around town an local areas no trips . I don't have to keep power glide

Originally Posted by Ken1960

I might be wanting too much , I'm going to drive car around town an local areas no trips . I don't have to keep power glide

Ken, it's not so much that you are wanting too much, it's that you don't have the expertise of knowing what to do and how to do it. Plus the problem of money. If I were to set out to do what you are thinking, I would have the know-how to do it, but would have to raise probably $20,000 for parts and machine work to get it done, far more than the vehicle would be worth after being finished. It's always cheaper to buy a hot ride than it is to build one.

How about going through a little exercise just on rear end parts upgrades. Begin by reading through this tutorial....
Chevrolet Chevelle Rear Control Arms - Angle Of Opportunity - Tech - Chevy High Performance Magazine
Price out the arms and frame braces from BMR Fabrication, then do some research on how much it costs to remove your control arms, re-inforce the frame structure and install the new control arms. This would be best done with the body off the chassis, so that you could de-rust and paint the frame. How much to de-rust the frame? How much to paint the frame? Where would the work be done? Do you have another ride while yours is down for 2 years? How about the 12-bolt? The housing will have to have brackets welded onto it (without warping the housing from the heat of welding) to fit your car and a new set of gears, bearings and a Positraction unit installed. Do you have a place to do that work? Can you weld?

Hopefully, you can begin to see how much effort and money goes into a fast car. This is just a few items at the rear and we already have a bill for over $3000, without even mentioning rear springs, shocks, tires, wheels or brakes. Your project can be done, but it takes expertise and money.

.

Still don't know what to do about my build. Might get a 454 from my friend and take off iron heads put aliumum heads on and a 750 carb don't want to redo hole car just want a strong runner