Big block conversion questions, help me please!
#1
Big block conversion questions
I've decided to convert my '69 to a big block. The 350 in the car is not the original engine and its tired and worn out. Converting the car to a big block isn't going to hurt its value because its not original anyway. I want to do the job as right as possible so that I wont have any issues with the conversion but I'm in a pickle as far as what to get for engine pulleys and brackets. The car has a/c and power steering so I picked up some original big block 'vette a/c compressor mounting brackets on ebay today and bought a power steering pump and alternator bracket kit from Zip corvette parts today too. I also scored an original big block 3 groove water pump pulley on ebay today for 100 bucks which sounds like a lot of money but its cheap compared to what the corvette supply places want for them. However, I haven't yet bought the crankshaft pulley and the power steering pump pulley because I have a feeling that I don't have to buy corvette specific pulleys for the crank and power steering pump, am I correct? Zip wants a whopping 229 bucks for a '65-early '69 crank pulley and 107.50 for a '65-'74 power steering pump pulley. They also list a late '69-'74 crank pulley for a more reasonable 53.50. Whats the difference between the '65-early '69 crank pulley and the late '69-'74 crank pulley? The power steering and alternator bracket kit I bought is the one listed for '65-'69 cars. They have one listed for '70-'74 cars too for the same price but since my car is a '69 I got the kit for '65-'69 cars. I'm assuming that the difference between them is because of the smog pump that came on the later cars? I'm not sure on that one though because my assembly manual shows the smog pump on the '69 even though mine doesn't have one. Do I have to use the 229 dollar '65-'69 crank pulley with the 65-69 alternator and power steering brackets or can I get away with using the 53.50 dollar '70-'74 crank pulley? Did all big block vettes use the short water pump or did they switch to the long water pump in '70? I think they all used the short water pump and if that's the case then I should be able to use the cheaper '70-'74 crank pulley, correct? I'm not building a "must be correct" show car, I just want to do the conversion as cheaply as possible. Also, I see that an idler pulley was used on the diagrams in my assembly manual but is it necessary on cars without a smog pump? Zip lists it as being used on '69-'74 cars with A/C and they want 144 bucks for it. Was there an idler pulley on the big block '65-'68 cars with A/C or is it only used on '69-'74 cars? Do I need that idler pulley? The belt diagrams in my assembly manual only show diagrams with the smog pump, it doesn't show any diagrams without it, and it shows the idler pulley as being all by itself, its not "idling" on the a/c, power steering, or alternator belt. My car isn't going to have a smog pump on it so I'm at a loss as to what I need as far as pulleys and brackets go now. Does anyone have some pics of a big block vette engine with A/C and power steering but no smog pump so that I can see what pulleys and brackets were used on it? I just ordered the 65-69 bracket kit today, I can call them first thing Monday morning and switch it to the 70-74 bracket kit if necessary.
Here is the '65-'69 power steering and alternator bracket kit:
http://www.zip-corvette.com/65-69-39...mount-kit.html
Here is the '70-'74 power steering and alternator bracket kit:
http://www.zip-corvette.com/70-74-45...mount-kit.html
Here is the 229 dollar '65-early '69 crank pulley:
http://www.zip-corvette.com/65-69e-3...le-groove.html
Here is the much cheaper 53.50 dollar late '69-'74 crank pulley:
http://www.zip-corvette.com/69l-74-4...le-groove.html
Here is the '69-'74 idler pulley:
http://www.zip-corvette.com/69-74-42...er-pulley.html
By the way, here's a 25 dollar crank pulley I found on e-bay for big blocks w/short water pumps but for some reason it says that it cant be used on corvettes even though it looks just like the late '69-'74 vette pulley from Zip, can anyone tell me why it wont work?:
http://www.ebay.com/itm/401174223035
Also, I found a two groove power steering pump pulley on e-bay that fits the early style power steering pumps that have the keyway on the shaft for 33 bucks, can I use this one instead of the expensive 107 dollar pulley from Zip?:
http://www.ebay.com/itm/322207493331
Also, what front springs should I get for a vette with an all iron big block with a/c?
By the way, here is the exhaust system I want to put on it, is there something better out there for around the same cost?:
http://www.ebay.com/itm/Maximizer-Ma...lWmpOH&vxp=mtr
Any help would be GREATLY appreciated!
Here is the '65-'69 power steering and alternator bracket kit:
http://www.zip-corvette.com/65-69-39...mount-kit.html
Here is the '70-'74 power steering and alternator bracket kit:
http://www.zip-corvette.com/70-74-45...mount-kit.html
Here is the 229 dollar '65-early '69 crank pulley:
http://www.zip-corvette.com/65-69e-3...le-groove.html
Here is the much cheaper 53.50 dollar late '69-'74 crank pulley:
http://www.zip-corvette.com/69l-74-4...le-groove.html
Here is the '69-'74 idler pulley:
http://www.zip-corvette.com/69-74-42...er-pulley.html
By the way, here's a 25 dollar crank pulley I found on e-bay for big blocks w/short water pumps but for some reason it says that it cant be used on corvettes even though it looks just like the late '69-'74 vette pulley from Zip, can anyone tell me why it wont work?:
http://www.ebay.com/itm/401174223035
Also, I found a two groove power steering pump pulley on e-bay that fits the early style power steering pumps that have the keyway on the shaft for 33 bucks, can I use this one instead of the expensive 107 dollar pulley from Zip?:
http://www.ebay.com/itm/322207493331
Also, what front springs should I get for a vette with an all iron big block with a/c?
By the way, here is the exhaust system I want to put on it, is there something better out there for around the same cost?:
http://www.ebay.com/itm/Maximizer-Ma...lWmpOH&vxp=mtr
Any help would be GREATLY appreciated!
Last edited by TheGreek!; 08-28-2016 at 07:42 AM.
#4
Race Director
I've had good luck a couple of times by getting the GM part number off the pic of the original Corvette part on eBay and then searching the part number. If it isn't Corvette specific, you can almost always find it cheaper.
#5
Safety Car
I've not done a bbc swap on a vette, but if I ever blow up my 400" I'll build a big block for it. I'm interested in what you come up with on your issues. Nothing wrong with an ls, but just for nothing I'd do a big block before an ls, nostalgia and no computers I guess.
#7
My 427 Crank pulley looks like this one
http://www.zip-corvette.com/69l-74-4...le-groove.html
http://www.zip-corvette.com/69l-74-4...le-groove.html
By the way, I discovered that the idler pulley was added so that the first belt could be adjustable, before they added the idler pulley there was no way to adjust the first belt. All the first belt does is drive the water pump, it doesn't drive any accessories.
Last edited by TheGreek!; 08-28-2016 at 03:04 PM.
#8
Le Mans Master
I did the SB to BB swap on my 71', I pretty much bought all of the repro stuff (brackets/pulleys) for a 71' LS5 with PS and AC.. Everything fit/worked pretty well. The PS pump mounting bracket did need some tweaking to get the belt alignment right. I used the cast iron PS pulley, 3 groove water pump pulley. I did add the tensioner for the deadman belt.
This setup isn't the cheapest but it works, looks correct and been pretty reliable for 18k miles now.
If you search my user name, I have a SB-BB swap thread I documented everything on. Lots of pics/info. It's way back from 08 I think.
A couple pics for reference..
This setup isn't the cheapest but it works, looks correct and been pretty reliable for 18k miles now.
If you search my user name, I have a SB-BB swap thread I documented everything on. Lots of pics/info. It's way back from 08 I think.
A couple pics for reference..
Last edited by ajrothm; 08-28-2016 at 03:28 PM.
#9
I've decided to convert my '69 to a big block. The 350 in the car is not the original engine and its tired and worn out. Converting the car to a big block isn't going to hurt its value because its not original anyway. I want to do the job as right as possible so that I wont have any issues with the conversion but I'm in a pickle as far as what to get for engine pulleys and brackets. The car has a/c and power steering so I picked up some original big block 'vette a/c compressor mounting brackets on ebay today and bought a power steering pump and alternator bracket kit from Zip corvette parts today too. I also scored an original big block 3 groove water pump pulley on ebay today for 100 bucks which sounds like a lot of money but its cheap compared to what the corvette supply places want for them. However, I haven't yet bought the crankshaft pulley and the power steering pump pulley because I have a feeling that I don't have to buy corvette specific pulleys for the crank and power steering pump, am I correct? Zip wants a whopping 229 bucks for a '65-early '69 crank pulley and 107.50 for a '65-'74 power steering pump pulley. They also list a late '69-'74 crank pulley for a more reasonable 53.50. Whats the difference between the '65-early '69 crank pulley and the late '69-'74 crank pulley? The power steering and alternator bracket kit I bought is the one listed for '65-'69 cars. They have one listed for '70-'74 cars too for the same price but since my car is a '69 I got the kit for '65-'69 cars. I'm assuming that the difference between them is because of the smog pump that came on the later cars? I'm not sure on that one though because my assembly manual shows the smog pump on the '69 even though mine doesn't have one. Do I have to use the 229 dollar '65-'69 crank pulley with the 65-69 alternator and power steering brackets or can I get away with using the 53.50 dollar '70-'74 crank pulley? Did all big block vettes use the short water pump or did they switch to the long water pump in '70? I think they all used the short water pump and if that's the case then I should be able to use the cheaper '70-'74 crank pulley, correct? I'm not building a "must be correct" show car, I just want to do the conversion as cheaply as possible. Also, I see that an idler pulley was used on the diagrams in my assembly manual but is it necessary on cars without a smog pump? Zip lists it as being used on '69-'74 cars with A/C and they want 144 bucks for it. Was there an idler pulley on the big block '65-'68 cars with A/C or is it only used on '69-'74 cars? Do I need that idler pulley? The belt diagrams in my assembly manual only show diagrams with the smog pump, it doesn't show any diagrams without it, and it shows the idler pulley as being all by itself, its not "idling" on the a/c, power steering, or alternator belt. My car isn't going to have a smog pump on it so I'm at a loss as to what I need as far as pulleys and brackets go now. Does anyone have some pics of a big block vette engine with A/C and power steering but no smog pump so that I can see what pulleys and brackets were used on it? I just ordered the 65-69 bracket kit today, I can call them first thing Monday morning and switch it to the 70-74 bracket kit if necessary.
Here is the '65-'69 power steering and alternator bracket kit:
http://www.zip-corvette.com/65-69-39...mount-kit.html
Here is the '70-'74 power steering and alternator bracket kit:
http://www.zip-corvette.com/70-74-45...mount-kit.html
Here is the 229 dollar '65-early '69 crank pulley:
http://www.zip-corvette.com/65-69e-3...le-groove.html
Here is the much cheaper 53.50 dollar late '69-'74 crank pulley:
http://www.zip-corvette.com/69l-74-4...le-groove.html
Here is the '69-'74 idler pulley:
http://www.zip-corvette.com/69-74-42...er-pulley.html
By the way, here's a 25 dollar crank pulley I found on e-bay for big blocks w/short water pumps but for some reason it says that it cant be used on corvettes even though it looks just like the late '69-'74 vette pulley from Zip, can anyone tell me why it wont work?:
http://www.ebay.com/itm/401174223035
Also, I found a two groove power steering pump pulley on e-bay that fits the early style power steering pumps that have the keyway on the shaft for 33 bucks, can I use this one instead of the expensive 107 dollar pulley from Zip?:
http://www.ebay.com/itm/322207493331
Also, what front springs should I get for a vette with an all iron big block with a/c?
By the way, here is the exhaust system I want to put on it, is there something better out there for around the same cost?:
http://www.ebay.com/itm/Maximizer-Ma...lWmpOH&vxp=mtr
Any help would be GREATLY appreciated!
Here is the '65-'69 power steering and alternator bracket kit:
http://www.zip-corvette.com/65-69-39...mount-kit.html
Here is the '70-'74 power steering and alternator bracket kit:
http://www.zip-corvette.com/70-74-45...mount-kit.html
Here is the 229 dollar '65-early '69 crank pulley:
http://www.zip-corvette.com/65-69e-3...le-groove.html
Here is the much cheaper 53.50 dollar late '69-'74 crank pulley:
http://www.zip-corvette.com/69l-74-4...le-groove.html
Here is the '69-'74 idler pulley:
http://www.zip-corvette.com/69-74-42...er-pulley.html
By the way, here's a 25 dollar crank pulley I found on e-bay for big blocks w/short water pumps but for some reason it says that it cant be used on corvettes even though it looks just like the late '69-'74 vette pulley from Zip, can anyone tell me why it wont work?:
http://www.ebay.com/itm/401174223035
Also, I found a two groove power steering pump pulley on e-bay that fits the early style power steering pumps that have the keyway on the shaft for 33 bucks, can I use this one instead of the expensive 107 dollar pulley from Zip?:
http://www.ebay.com/itm/322207493331
Also, what front springs should I get for a vette with an all iron big block with a/c?
By the way, here is the exhaust system I want to put on it, is there something better out there for around the same cost?:
http://www.ebay.com/itm/Maximizer-Ma...lWmpOH&vxp=mtr
Any help would be GREATLY appreciated!
Any short water pump 2 groove crank pulley will work. As has been stated and shown the first belt goes directly from crank to water pump so their is no way to tighten it, and yes it does drive the accessories in a way because other stuff is driven off just the water pump, so that belt has a lot of stress on it.
I have a extra idler pulley, PS pump with pulley and brackets, and alt bracket setup left
over. Too bad you didn't do a shout out before you bought all your parts.
Anyway it is a pretty easy conversion. I found exhaust manifolds on Ebay that were original 69, not cheap reproductions, and Flowmaster makes a nice stainless exhaust kit that bolts on to factory manifolds.
I used a LS-6 intake so the factory hood clears with square port heads. The distributors are the same so you will still have your tach drive.
PM me if you want that idler I am going to put it on eBay.
#10
First off let me just say I HATE YOU! Now that I have that off my chest, I have been looking for a 3 groove pulley, and you found one for a 100 bucks! OK just kidding about the I hate you part. Good job on scoring one of those.
Any short water pump 2 groove crank pulley will work. As has been stated and shown the first belt goes directly from crank to water pump so their is no way to tighten it, and yes it does drive the accessories in a way because other stuff is driven off just the water pump, so that belt has a lot of stress on it.
I have a extra idler pulley, PS pump with pulley and brackets, and alt bracket setup left
over. Too bad you didn't do a shout out before you bought all your parts.
Anyway it is a pretty easy conversion. I found exhaust manifolds on Ebay that were original 69, not cheap reproductions, and Flowmaster makes a nice stainless exhaust kit that bolts on to factory manifolds.
I used a LS-6 intake so the factory hood clears with square port heads. The distributors are the same so you will still have your tach drive.
PM me if you want that idler I am going to put it on eBay.
Any short water pump 2 groove crank pulley will work. As has been stated and shown the first belt goes directly from crank to water pump so their is no way to tighten it, and yes it does drive the accessories in a way because other stuff is driven off just the water pump, so that belt has a lot of stress on it.
I have a extra idler pulley, PS pump with pulley and brackets, and alt bracket setup left
over. Too bad you didn't do a shout out before you bought all your parts.
Anyway it is a pretty easy conversion. I found exhaust manifolds on Ebay that were original 69, not cheap reproductions, and Flowmaster makes a nice stainless exhaust kit that bolts on to factory manifolds.
I used a LS-6 intake so the factory hood clears with square port heads. The distributors are the same so you will still have your tach drive.
PM me if you want that idler I am going to put it on eBay.
#11
Burning Brakes
Since it's not original anyway why not use a March kit, works much better and cost about the same.
I used this kit (I don't have A/C), but they also have kits with A/C:
https://www.summitracing.com/int/par...0560/overview/
/Karsten
I used this kit (I don't have A/C), but they also have kits with A/C:
https://www.summitracing.com/int/par...0560/overview/
/Karsten
The following users liked this post:
AirBusPilot (04-01-2018)
#12
Since it's not original anyway why not use a March kit, works much better and cost about the same.
I used this kit (I don't have A/C), but they also have kits with A/C:
https://www.summitracing.com/int/par...0560/overview/
/Karsten
I used this kit (I don't have A/C), but they also have kits with A/C:
https://www.summitracing.com/int/par...0560/overview/
/Karsten
#13
I did the SB to BB swap on my 71', I pretty much bought all of the repro stuff (brackets/pulleys) for a 71' LS5 with PS and AC.. Everything fit/worked pretty well. The PS pump mounting bracket did need some tweaking to get the belt alignment right. I used the cast iron PS pulley, 3 groove water pump pulley. I did add the tensioner for the deadman belt.
This setup isn't the cheapest but it works, looks correct and been pretty reliable for 18k miles now.
If you search my user name, I have a SB-BB swap thread I documented everything on. Lots of pics/info. It's way back from 08 I think.
A couple pics for reference..
This setup isn't the cheapest but it works, looks correct and been pretty reliable for 18k miles now.
If you search my user name, I have a SB-BB swap thread I documented everything on. Lots of pics/info. It's way back from 08 I think.
A couple pics for reference..
#14
Le Mans Master
You can see in the first pic the PS pump pulley looks **** eyed and the belt looks crooked... Yeah the repro PS bracket was not 100% true.. It took a few attempts at straightening it out to get it all to line up right with correct belt alignment. Not a huge deal, just a pain in the ***.
#15
First off let me just say I HATE YOU! Now that I have that off my chest, I have been looking for a 3 groove pulley, and you found one for a 100 bucks! OK just kidding about the I hate you part. Good job on scoring one of those.
Any short water pump 2 groove crank pulley will work. As has been stated and shown the first belt goes directly from crank to water pump so their is no way to tighten it, and yes it does drive the accessories in a way because other stuff is driven off just the water pump, so that belt has a lot of stress on it.
I have a extra idler pulley, PS pump with pulley and brackets, and alt bracket setup left
over. Too bad you didn't do a shout out before you bought all your parts.
Anyway it is a pretty easy conversion. I found exhaust manifolds on Ebay that were original 69, not cheap reproductions, and Flowmaster makes a nice stainless exhaust kit that bolts on to factory manifolds.
I used a LS-6 intake so the factory hood clears with square port heads. The distributors are the same so you will still have your tach drive.
PM me if you want that idler I am going to put it on eBay.
Any short water pump 2 groove crank pulley will work. As has been stated and shown the first belt goes directly from crank to water pump so their is no way to tighten it, and yes it does drive the accessories in a way because other stuff is driven off just the water pump, so that belt has a lot of stress on it.
I have a extra idler pulley, PS pump with pulley and brackets, and alt bracket setup left
over. Too bad you didn't do a shout out before you bought all your parts.
Anyway it is a pretty easy conversion. I found exhaust manifolds on Ebay that were original 69, not cheap reproductions, and Flowmaster makes a nice stainless exhaust kit that bolts on to factory manifolds.
I used a LS-6 intake so the factory hood clears with square port heads. The distributors are the same so you will still have your tach drive.
PM me if you want that idler I am going to put it on eBay.
I have a 3 groove pulley for the WP, just sitting now. I installed a March system on my LS-5, that I just rebuilt. I have the front of the motor, newer water pump, all the pulleys, the old A/C compressor, a newer Sanden compressor that was never charged with Freon, alternator, power steering pump, the block that goes on the A/C compressor, crank pulley....have I missed anything? I'd be willing to part with this stuff too
#16
#17
I have a 3 groove pulley for the WP, just sitting now. I installed a March system on my LS-5, that I just rebuilt. I have the front of the motor, newer water pump, all the pulleys, the old A/C compressor, a newer Sanden compressor that was never charged with Freon, alternator, power steering pump, the block that goes on the A/C compressor, crank pulley....have I missed anything? I'd be willing to part with this stuff too
I will buy it if you want to sell it.
The following users liked this post:
Bandit54 (08-29-2016)
#18
#19
Melting Slicks
The alternator pulley is different as well, wrong pulley may line up but will probably give you trouble getting the standard belt tight enough before running out of adjustment.
http://www.zip-corvette.com/66-74-al...FcVahgodF00KTA
#20
Are you aware there are two different size arbors on big block water pumps? The early ones, up until mid 70, maybe 71, had a 5/8" arbor. Later went to larger, think it may have been 3/4". You'll need to match the pump to your pulley, center hole on the pulley, smaller is correct for early big blocks.
The alternator pulley is different as well, wrong pulley may line up but will probably give you trouble getting the standard belt tight enough before running out of adjustment.
http://www.zip-corvette.com/66-74-al...FcVahgodF00KTA
The alternator pulley is different as well, wrong pulley may line up but will probably give you trouble getting the standard belt tight enough before running out of adjustment.
http://www.zip-corvette.com/66-74-al...FcVahgodF00KTA