Big Block advice please
 

Hi all,

If u've read some of my older posts you will already know that i wish to buy a new more powerful engine for my 1977 Camaro. Currently i have a small block 305 and had been thinking off a 383 or an 400 small block. I do like alot of HP, but it's more about having a large V8 rumble.
I have been offered a 454 big block, for quite a good price. It was taken out of a car that has now been scrapped. The engine is running well, with no knocks etc, but history of the engine is abit unknown. If i did buy the engine, i would not fit it until i had got it serviced and all the ancillaries replaced. To try and make sure it's a reliable engine.
Can someone please tell me, what issue's I'm likely to have with fitting a Big Block into a 77.

new headers required
new front springs required for the heavy big block
engine mounts?
currently have a 1989 radiator fitted,which keeps the needle below 150 on the small block. Unless stuck in a traffic jam, but it quickly cools down.
TH350 trans with B&M re-build kit
will i need to upgrade the torque converter?
Will the small block heater core be a problem?, if so can i just bypass the heater core?

Any advice / tips would be very helpful thanks from Luke

Boy this one has been done to death! Did you try the search feature?
I've done a number of these swaps, and you don't need new springs unless your springs are already sagging. I just put new springs in my big block Camaro and didn't want it sitting a mile high, so I installed new springs for a smallblock AC Camaro.
Stock mounts for the SBC will fit on the BBC engine.
If your radiator gets hot idling, then replace it with a 4 core BBC radiator, or a 2 row with 1" rows. A BBC will run hotter and it needs the longer radiator that's also thicker.
Trans and converter will work great if they're built properly. Use good clutches and a shift kit.
The heater core will work, but not with tall valve covers. But if you pull the heater while the engine is out, you can turn the core 180 degrees and punch two new holes for the outlets and it will work great with all valve covers. Better put a new one in at that time too! Or just take it all out and blank it off if you don't winter drive.
Headers? YES! But do some asking around before and you wont end up with headers that don't fit well. Cheap headers will work in some brands, and in others they're just a nightmare. The cheap Summit headers actually work well, but drop them in the engine compartment before you drop the engine in and then just bolt them up after the engine is mounted.

....^be my mentor lol

No i didn't use the search function, i will check it out and see what else i can find.
can you please tell me how to measure the front ride height, so i know if i need new front springs. They are the original one's and seem ok, but i have nothing to compare them against.
Thanks

Not sure of a measurement with a stock smallblock. I could measure mine with the big block since they are new and then you can see if your's is higher or the same. If it's the same as mine, then they will sag a bit more with a big block and thus you'll want new.
When I got my car it had the original big block springs in it and it sat too high, so I went to smallblock springs because nobody sold lowering springs back then. I know the big block springs will sit way too high for what most people want.

Yeah if you could let me know your hide height that would be great thanks. How is the balance / ride of your car feel from small block to big block. A Camaro owner here in the UK has adviced me not to fit a Big Block as it will upset the balance of the car. He has a small block and i don't think he has ever had a Big Block.
thanks

Well I've never had a smallblock, so I have only driven the few we've converted to BBC prior to conveting. I doubt anyone could tell the difference in handling or front to rear weight ratio between the two engines. Afterall it's only 110 lbs. more than a small chevy V8. 575 lbs. for SBC and 685 lbs. for BBC.
Engine Weight FYI

If they can tell there's another 110 lbs. on the frontend, then they also will notice the car handling different with a 180 lb. passenger. I'm calling BS on anyone who can do that.

An experienced road course racer will notice the extra weight in the nose when he hits the turns. But I wouldn't worry about the weight in a street car. If you want to see what your ride height will be, just put some weight over the engine area (sand bags, etc.) that equals the 110 lb. difference. Or sit the girl friend on the air cleaner. ;)

OK, so I measured mine from a point that would be generic and not depend on wheels or tire size. From the center of the front spindle, straight up to the edge of the wheelwell opening is 13.5", with the new smallblock AC springs.
So you can meausre your's at the same location and see how much difference your car is to mine. I have no rubbing issues, or handling issues.

Luke – You’ll definitely need some new front coil springs in order to make up for the additional weight over the front wheels. Stock small block springs will sag and not support the weight correctly.

http://www.hotchkis.net/_uploaded_fi...4promo_pic.jpg


Pick up some reproduction ’70-’72 big block frame stands (the lower half of the engine mount that attaches to the frame, if you want the engine to sit in the frame in the factory big block location so big block headers fit correctly. Big blocks can always use additional cooling and only time will tell if your current upgraded radiator will be sufficient. A TH350 will have a short lifespan behind even a mild big block, but it will work for a while. We suggest using the TH350 converter until the trans stops working, then get a better transmission and converter. The small block heater core will hook up but it’s a tight fit. Bypassing the heater core (and/or not using the short bypass hose on a big block from the top of the water pump to the intake manifold) will leave air bubbles trapped under the thermostat and cause it not to function correctly. To avoid this, you can use the old trick of drilling 2 1/8” holes in the thermostat to allow trapped air to bleed through so hot water can correctly operate your thermostat. This is a trick that should actually be used on all high performance big and small block Chevy’s, even if you are using a heater core and a bypass hose.

http://i16.photobucket.com/albums/b4...thermostat.jpg