Help with my 69 Chevelle 396

[convss]

Hey guys so thought I'd ask u guys something,I want some more power in the Chevelle , I have 3k to spend , I a bare 427 block and a extra set of closed chamber oval port heads , should I put the 3k into building that motor or put the 3k into the 396 motor , I have the 350hp l34 , with headers and torker 2 , 780 holly dubble pumper 4 brl , my thought was to build the 427 motor , save the 396 motor for back up or if I ever want to put it back in

My son had a 1970 SS396 chevelle, and did just what you are contemplating. I say go for it, my son was very happy with the result!

[Brian28]

Hey guys so thought I'd ask u guys something,I want some more power in the Chevelle , I have 3k to spend , I a bare 427 block and a extra set of closed chamber oval port heads , should I put the 3k into building that motor or put the 3k into the 396 motor , I have the 350hp l34 , with headers and torker 2 , 780 holly dubble pumper 4 brl , my thought was to build the 427 motor , save the 396 motor for back up or if I ever want to put it back in

[Brian28]

On my build sheet was a number , 796 , I found 796 on the car today, what would this number be for ?

[Brian28]

On line I seen ppl that had them scaned to pull up what they couldn't see that good , there is a lot more on it I can't make out ,

[Brian28]

Yeah I looked all over the car , I had the dash down , I put down new carpet , I lowerd the gas tank a lil , I found that one under the back seat ,

[dieselhead]

Is there a place I can take that build sheet too that can scan it , to pull up the stuff I can't make out

I never heard of a way to scan the build sheet but you can find a typical build sheet online that might give you some clues. My build sheet was under the carpet but the oil on the weather proofing on the floorboard stained the sheet so bad it was unreadable plus a lot of it had just crumbled. I hope there's another one on top of my gas tank but I doubt it.

[Brian28]

Yeah I just changed all fluids every fluid is brand new , maybe I'll try the speed and rpm way

[yellomalibu]

Probably not a bad idea to service the rear diff, anyway - and as SBG and Bob suggested, while you have the rear diff cover off to drain out the old fluid, you either look for the marks on the ring gear or count teeth and do the division.

If you don't want to do that, you can use a gps app on your phone to determine your exact speed (in 4th gear) to make sure your speedo is accurate, make note of the RPM's at that speed, then come home and find an online RPM - Gear calculator. The only other piece of information you'll need is tire height.

[Deaf Bob]

The numbers SBG is talking about are on the ring gear.. You need to drain and pull the rear cover to see it..
I use "The Right Stuff" a grey colored silicone that is a bear to remove once on and set up in place of a gasket..
OR you can count the teeth on the ring gear and pinion both. Divide the bigger by the smaller.. Be same numbers SBG was talking of ..

[Brian28]

Is there a place I can take that build sheet too that can scan it , to pull up the stuff I can't make out

[Brian28]

I got all the bushings and shocks done on the back its so much better I can get on it without the hopping now , the old shocks where toast , I could push them up and they would just stay up , feels so good now , I did the front a few weeks ago , hole new car

[Brian28]

Yeah I don't see anyother numbers on it , what would have came stock or are there a few different ones

[Brian28]

Where would it be at , I don't see any other numbers

[SuperBuickGuy]

Look for the numbers on the ring gear - you're looking for something that says 41 7, 43 9.... and it will be in that format two numbers, a space, then another number or two. You figure out your gear ratio by dividing the 1st number by the 2nd.

[Brian28]

Can u tell me what gears I have