Thread: 402 BB and TQ Converter Questions

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Hi Yall, im putting my first project together and have no clue about motors.
I bought a 402 bb bored 30 over with 15cc ceramic dome pistons, 427 corvette heads and it has a 472 lift with 282 duration and roller rockers. I have no idea what all this means or if i wrote it down right but thats what they told me. Could yall guesstimate how much hp this thing would put out? Another question I have is what or how big of a torque converter would i need. Im hooking it up to a two speed powerglide and im not sure if i need to have a stall or not. Any help would be appreciated.

not sure of chamber volume, but sounds to me like it might have high compression with those domes. Do you know the casting numbers on those heads, probably rect. ports being from the 427 corvette. That would've been late 60"s I believe. I really don't have a power estimate but I would throw around the numbers of at least 400 HP and 450 lbs of torque. I don't think you need a big stall but some wouldn't hurt, maybe 2500? More info is needed to really be more accurate, give more numbers and the components you're going to use. Casting numbers are great. And if the heads have been milled your compression is going to be higher.

A lot of assumptions here like headers and I could not find the cam you stated, very low lift cam for the duration. Used a 279 duration cam with 510 lift.
HP - 400
TQ - 450
a stall of 2500 is recommended

I had the casting number from the heads but have seemed to misplaced them at the moment. I went ahead with a 2500 stall converter and the mechanic should have it fired up today hopefully. Thanks for the advice!! i'll let yall know how it turns out.

Well, how did it turn out?

Sorry it's taking a while. It took them a while to get the headers in place. I still have not heard it run yet! Just needs a radiator power steering pump and alternator and a while lot of electrical stuff like the blinkers and ect. I'll let ya know how it goes.

Bit of info needed
Vehicle weight, rear gears, intended use,
Cam size if you got it figured out

Seems you've dragged 2 old posts back up.. this one from January 2011. Hope you're not waiting for them to reply!??!

Originally Posted by t-top havoc

Bit of info needed
Vehicle weight, rear gears, intended use,
Cam size if you got it figured out

Vehicle weight is roughly 3900lbs. It is a 79 Trans am.
I was told when I purchased the shell that it had 3.73 gears.
Intended use is more street than strip since the closed one is 2 hours away.
I was unable to find any additional info on the cam. I'll just have to use the seat dyno once I get it rolling on its own.

I know this is an old post but I kinda wandered off for 2 years with other hobbies and now I have to work on it or the Lady of the house threatens to make me sell it.

Originally Posted by MasnarT

now I have to work on it or the Lady of the house threatens to make me sell it.

Are you a man or a mouse? Squeak up!!!!
.
.

Originally Posted by MasnarT

I know this is an old post but I kinda wandered off for 2 years with other hobbies and now I have to work on it or the Lady of the house threatens to make me sell it.

Glad you made it back to us! Now, Get'er DONE! And roar like a lion! LOL..

Originally Posted by techinspector1

Are you a man or a mouse? Squeak up!!!!
.
.

Haha I'm trying! I'm still trying to figure out her Colombian mind. Not your typical American woman. I'll remember that from now on though.

Originally Posted by 34_40

Glad you made it back to us! Now, Get'er DONE! And roar like a lion! LOL..

Thank you! I plan to get it up and running. No more breaks or other hobbies until she is done! I'm putting my foot and funds down this time!

Access to a dial gauge & stand?
What you need to do is measure the lift & base of the cam by attaching the gauge to a rocker then by hand ( breaker bar ) roatate the motor.
I know there is a formula to get .50 lift but I cant add to that.
Hopefully Pat will be able to chime in with more apropriate & true direction.
( edit )
Cam size plays into torque converter.
You want the stall to be well within the cam // heads power band

Hope this helps rather than confuse!!

Originally Posted by t-top havoc

Access to a dial gauge & stand?
What you need to do is measure the lift & base of the cam by attaching the gauge to a rocker then by hand ( breaker bar ) roatate the motor.
I know there is a formula to get .50 lift but I cant add to that.
Hope this helps rather than confuse!!

With a magnetic base & dial INDICATOR and a degree wheel, you can measure and document the cam profile, but before trying all that, maybe you can get the numbers off the front of the cam?

Post up the numbers and maybe folks here can identify the cam (if you can't).

Originally Posted by 34_40

With a magnetic base & dial INDICATOR and a degree wheel, you can measure and document the cam profile, but before trying all that, maybe you can get the numbers off the front of the cam?

Post up the numbers and maybe folks here can identify the cam (if you can't).

Indicator!!
DOH!!!
Thanks for the correction!!
Big difference in " gauge " & " indicator "!!