bennie442s

I am building my 1970 Oldsmobile Vista Cruiser right now and will be swapping in a 455 and 200-4R transmission. The transmission is from an 86 Monte Carlo (has the universal bolt pattern) will be rebuilt and upgraded to handle the higher horse power and torque levels my engine will be making compared to the transmissions original 305 power plant. The 455 is bored .030 over, 10.25:1 compression pistons, internal balance, with Edelbrock heads. I will be doing an EFI multi-port set up. Car is running the original 3.23 12 bolt rear end. I have done extensive search of the classicolds forums, but have developed a few questions from reading multiple threads.
-Lock up vs. non-lock up torque converters? I understand better fuel economy with the lock up converter, but have read a few articles (including a hot rod/ car craft article) extolling the virtues of going with a 10 inch non-lock out. What is the best way to go? Are there reliable non-ecm kits lock out kits available, if so which kit is recommended?
-What stall speed torque converter should I pick?
-how much vacuum is needed to properly operate the transmission, which camshaft is recommended to make the balance between creating enough vacuum all the while helping me reach the 450 hp goal.
-the bow tie universal TV cable kit seems to be highly recommended, is this correct? Is there a better brand?

Thanks,
-ben

joe_padavano

Well, unless you WANT to be running around at 3500 RPM all the time, you do NOT want a 10" converter in a heavy VC for the street. Don't confuse drag strip advice with what makes sense for a heavy cruiser. The reason for a small diameter, high stall converter is to let you launch your drag car at the torque peak of the engine. It is NOT what you want for pulling away from stoplights in a station wagon. More importantly, the torque peak for a 350 Chevy race motor is very different that the torque peak for a 455 Olds motor. Match the converter stall speed to the engine, application, gears, and intended use.

If by "lockout" you mean lock up, there at LOTS of kits. They range from a simple toggle switch to vacuum and RPM sensitive systems. All you ultimately need to do is to apply 12V to the lockup solenoid.

See above.

None. The 200-4R uses a TV cable, not a vacuum modulator.

That's a function of the rest of your combo. Power brakes? A/C? Etc, etc.

Stock GM works, however I don't know how that interfaces with your aftermarket EFI.

bennie442s

Joe,
Thank you very much for your reply and please excuse my neophyte status on this topic.
-Very correct, absolutely do not want a 3500 stall converter in this build! I do not plan to be at WOT upon every stoplight launch. I am curious about what stall speed to pick from say a factory range of 1600 to 2400. In this application should I keep it lower similar to a delta 88 torque converter or should I go up to the Grand National torque converter stall speed of 2400, or somewhere in between? Just curious on your thoughts.
-What has me hung up on vacuum supplied by the motor is not the TV cable, but rather the aftermarket lockup kits refer to supplying a "vacuum switch." Not sure how much vacuum is required to operate this unit. Here is a link for reference: http://www.jegs.com/i/TCI/890/376600...oductId=748599
-Am I better off with one of these kits or wiring a 12V supply to the solenoid switch. Once again I am a neophyte on this topic, but from what I understand a person can either wire a simple 12v toggle switch, or add the brake pedal switch into the equation so that when the brake pedal is hit the lockup feature is disengaged. Is this a correct understanding, do you advocate this method?
-Car will have a full range of accessories including factory power assist disc brake (front) and drum rear. A/C, Power steering etc. Any thoughts on a good aftermarket cam set up?


Thanks for the help and sharing your expertise on this topic.
-ben

joe_padavano

That lockup kit senses vacuum only as an indicator of wide open throttle, as manifold vacuum drops to near zero at WOT. Normal vacuum at idle and part throttle is irrelevant for that kit, so long as it is above 10 in hg or so, which it will be. This is not a critical issue.

bobus8

I'm running a 455 in 77 cutlass S with 200_R4 using a 2500 Torque converter. (Non lockup). It's been fine so far. As far as lock up or non lockup, I just didn't want the hassle. I'm also running a fairly wild street cam (243/250) but I wanted the engine to lope.


Vacuum for the brakes is Low to say the least but for myself, it is enough.


A general suggestion for a cam, would be something in the 235 to 245 at .050 range. Although you're running the edelbrock aluminum heads, the 10.25 CR will need a little bit of a cam to help with pre-ignition.


There are other enthusiasts on the site that will suggest cams also.


Also, you can speak with the engineers from the cam manufacturers for recommendations.