350/454 swap
Thread Starter
Intermediate
Joined: Jan 2015
Posts: 45
Likes: 1
From: Killeen Texas
350/454 swap
Ive had my 77 for about 2 weeks now. After going thru and doing some maintenance and tune ups I was going to get a valve job. Pulled the heads and found a messed up cylinder. Went to a local shop to get some prices. The guy said he knew of a full 454 for the same price itd cost to machine it. Jumped on it for only $350. 
Its all stock from intake to oil pan and flexplate to water pump, including exhaust manifolds, brackets, and gaskets. After researching, everyone says that Ill need new exhaust, pulleys, brackets, and springs. What is the best budget headers? Do block huggers hook straight to the exhaust pipe? For the pulleys and brackets, since I have the original brackets do those fit or are there different ones? Do the pulleys or the fan from the 350 fit the 454? Springs are last one the list, but Im not sure what to upgrade them to.
Its all stock from intake to oil pan and flexplate to water pump, including exhaust manifolds, brackets, and gaskets. After researching, everyone says that Ill need new exhaust, pulleys, brackets, and springs. What is the best budget headers? Do block huggers hook straight to the exhaust pipe? For the pulleys and brackets, since I have the original brackets do those fit or are there different ones? Do the pulleys or the fan from the 350 fit the 454? Springs are last one the list, but Im not sure what to upgrade them to.
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
Headers- Hedman 2", painted, jegs/summit = $250
Springs- O Reilys auto sells Moog big block replacement springs= $69
Small block brackets and pullies will not work on the BB. You can buy all that stuff new (repro) from the Vette parts vendors, but get ready to pay...it ain't cheap. You'll spend $1k easy on repro brackets/pullies.
The fan should work from the 350. (7 blade with thermal clutch).
You'll have to have new exhaust ran to connect to the headers.
This swap is not as cheap as you think it will be. It is worth it if you want a big block, but definitely not budget.
Junk yard/swap meet/ebay parts can help you keep the cost down some.
I made the swap, I bought all new/repro stuff, I spent a fortune... But I love it when I pop the hood and see those fat valve covers.
Good luck.
Springs- O Reilys auto sells Moog big block replacement springs= $69
Small block brackets and pullies will not work on the BB. You can buy all that stuff new (repro) from the Vette parts vendors, but get ready to pay...it ain't cheap. You'll spend $1k easy on repro brackets/pullies.
The fan should work from the 350. (7 blade with thermal clutch).
You'll have to have new exhaust ran to connect to the headers.
This swap is not as cheap as you think it will be. It is worth it if you want a big block, but definitely not budget.
Junk yard/swap meet/ebay parts can help you keep the cost down some.
I made the swap, I bought all new/repro stuff, I spent a fortune... But I love it when I pop the hood and see those fat valve covers.
Good luck.
Thread Starter
Intermediate
Joined: Jan 2015
Posts: 45
Likes: 1
From: Killeen Texas
I read that the brackets and pulleys were expensive, but are the original 454 brackets ok to use? I pulled the A/C so thats not included, but can i use the same alternator and power steering ( just with new pulleys). I was going to try to match them up and see if they fit (crank pulley too)
I didnt exactly mean budget, lol. Although I do want it kind of cheap so I can drive it for now. I have another 454 that Im building but thatll be awhile before I get it completed. This is more to have it ready for a big block when the time comes.
I didnt exactly mean budget, lol. Although I do want it kind of cheap so I can drive it for now. I have another 454 that Im building but thatll be awhile before I get it completed. This is more to have it ready for a big block when the time comes.
Melting Slicks
Joined: Apr 2006
Posts: 2,084
Likes: 14
From: Airdrie Alberta
I made the swap, I bought all new/repro stuff, I spent a fortune... But I love it when I pop the hood and see those fat valve covers.
I used my 350 engine mounts, upper rad hose, starter.
I tried messing with the 350 pulley's but had clearance problems. I have seen much cheaper repos on line that i would like to investigate
My springs had been upgraded to 460lb during my resto and I just swapped in a new Dewitts rad so no cooling issues
My 454 has Aluminum heads, intake, water pump so the weight isn't too much more than the 350
Like they say it wasn't cheap but its going to be a blast!
Thread Starter
Intermediate
Joined: Jan 2015
Posts: 45
Likes: 1
From: Killeen Texas
I used my 350 engine mounts, upper rad hose, starter.
I tried messing with the 350 pulley's but had clearance problems. I have seen much cheaper repos on line that i would like to investigate
My springs had been upgraded to 460lb during my resto and I just swapped in a new Dewitts rad so no cooling issues
My 454 has Aluminum heads, intake, water pump so the weight isn't too much more than the 350
Like they say it wasn't cheap but its going to be a blast!
I tried messing with the 350 pulley's but had clearance problems. I have seen much cheaper repos on line that i would like to investigate
My springs had been upgraded to 460lb during my resto and I just swapped in a new Dewitts rad so no cooling issues
My 454 has Aluminum heads, intake, water pump so the weight isn't too much more than the 350
Like they say it wasn't cheap but its going to be a blast!
Le Mans Master
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
Hi, I did the swap in my 77 and went with the Dewitts radiator too, works great.
I used a long water pump with the alt on the right
side. Plenty of room to work with the ps of the left. I like it, lots of fun and it all fits under the stock 77 hood. Good luck with your swap.
I used a long water pump with the alt on the right
side. Plenty of room to work with the ps of the left. I like it, lots of fun and it all fits under the stock 77 hood. Good luck with your swap.
Melting Slicks
Joined: Apr 2006
Posts: 2,084
Likes: 14
From: Airdrie Alberta
but does the fan fit under the stock fan shroud? Your air cleaner looks like it sits kind of high, does it fit under the stock hood or did you replace it?
I am running a performer intake on mine , drop base air filter, Qjet & 3" filter element was hitting the hood. Changing to a 2"X 14" element the hood closes.....i'm still playing around with it and just changed to a Quick Fuel 750 carb
Is yours Automatic or 4 speed?
Thread Starter
Intermediate
Joined: Jan 2015
Posts: 45
Likes: 1
From: Killeen Texas
Mines an automatic. It was a stock L48, but it seems that Bubba had some fun with it. I had an Edelbrock Performer intake and a Holley 650 carb and I couldnt fit in a stock air filter. I was worried about having the same problem on the 454, but the intake looks lower.
What kind of headers did you use?
John65, that looks awesome.
Looking at these just makes me even more excited. You guys are great. Thanks
What kind of headers did you use?
John65, that looks awesome.
Looking at these just makes me even more excited. You guys are great. Thanks
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Melting Slicks
Joined: Apr 2006
Posts: 2,084
Likes: 14
From: Airdrie Alberta
I used the painted steel 2" Headman headers. I had to massage them a bit on the right side by the frame rail and they are a snug fit by the steering box...not sure if my fitment issues is due to raised exhaust ports on my aluminum heads.
The rest of my exhaust consists of the factory 2 1/2" with stainless Magnaflow mufflers, has a nice rumble but not excessive for cruising
http://www.summitracing.com/int/part...model/corvette
The rest of my exhaust consists of the factory 2 1/2" with stainless Magnaflow mufflers, has a nice rumble but not excessive for cruising
http://www.summitracing.com/int/part...model/corvette
Pro
Joined: Dec 2004
Posts: 534
Likes: 2
From: Connecticut
my fan was just touching the rad so i put a flex fan on to get it running. I find the flex fan is too noisy and sounds like a dump truck reving at 10,000rpm so i'm going to find some bbc pulley's and put the stock clutch fan on. For the fan shrould i removed the extension that was on mine.
I am running a performer intake on mine , drop base air filter, Qjet & 3" filter element was hitting the hood. Changing to a 2"X 14" element the hood closes.....i'm still playing around with it and just changed to a Quick Fuel 750 carb
Is yours Automatic or 4 speed?
I am running a performer intake on mine , drop base air filter, Qjet & 3" filter element was hitting the hood. Changing to a 2"X 14" element the hood closes.....i'm still playing around with it and just changed to a Quick Fuel 750 carb
Is yours Automatic or 4 speed?
Drifting
Joined: Aug 2004
Posts: 1,883
Likes: 124
From: Lubbock TX
If the engine you bought is stock, your compression will be something short of 8:1. At least get that taken care of an install a decent cam before you drop it in or you'll get tired of looking at smallblock car's tail lights.
No need for 2" headers, either - 1 3/4" are plenty for up to around 650hp. Headers that are too large don't scavenge nearly as well due to lower velocity.
It's possible to use early 90's smallblock serpentine brackets with adapters, probably the least expensive route.
No need for 2" headers, either - 1 3/4" are plenty for up to around 650hp. Headers that are too large don't scavenge nearly as well due to lower velocity.
It's possible to use early 90's smallblock serpentine brackets with adapters, probably the least expensive route.
Melting Slicks
Joined: Apr 2006
Posts: 2,084
Likes: 14
From: Airdrie Alberta
Could you post a picture of your radiator and fan setup?
Dewitts direct fit
This is with 350 pulleys shimmed to fit. I'm worried about balance issues and don't like the noisy fan so i'm going to find proper bbc pulleys and use the stock fan
Racer
Joined: Apr 2010
Posts: 352
Likes: 1
From: Central NJ
I did a 468 swap on my 74 a while back and I came across a lot of things people did not mention needed to be changed (or made...depending on how you approach things)
I did not get to read all the posts so forgive me if I am repeating any information. IIRC you will need:
Pulleys/Belts
Water pump (different shaft size)
2 Power steering hoses (can't remember which 2)
Radiator is different but if you're not upgrading the motor the stock small block one will do temporarily
Wiring is different but can easily modify the stock harness
Fuel pump is different but will be fine if you're not pushing a bunch of power
I cannot speak for ac or emissions because I deleted both of those.
I know I'm missing a few small things but I hope that helps
I did not get to read all the posts so forgive me if I am repeating any information. IIRC you will need:
Pulleys/Belts
Water pump (different shaft size)
2 Power steering hoses (can't remember which 2)
Radiator is different but if you're not upgrading the motor the stock small block one will do temporarily
Wiring is different but can easily modify the stock harness
Fuel pump is different but will be fine if you're not pushing a bunch of power
I cannot speak for ac or emissions because I deleted both of those.
I know I'm missing a few small things but I hope that helps
Thread Starter
Intermediate
Joined: Jan 2015
Posts: 45
Likes: 1
From: Killeen Texas
I already ordered the pulleys so I guess the serpentine is out, lol. Still looking for headers and its a toss up between shortys and block huggers. Im looking at cams and there are sooo many to choose from. I was looking at a Comp Cam Thumpr, anyone familiar with it? They seem to emphasize the idle and not so much the power.
http://www.summitracing.com/parts/cc...make/chevrolet
http://www.summitracing.com/parts/cc...make/chevrolet
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
I had a 383 sb built and hated it, I swapped it for a 454 that has oval post heads and perhaps a mild cam, auto tranny,
We swapped the 383 out and the 454 in and I drove the car home 100 miles the next day...hard? nope....
We swapped the 383 out and the 454 in and I drove the car home 100 miles the next day...hard? nope....
Thread Starter
Intermediate
Joined: Jan 2015
Posts: 45
Likes: 1
From: Killeen Texas
So far Ive ordered the BBC long water pump pulleys and a set of shorty headers. Am I correct in assuming that if they fit a '73 with a big block it should fit fine in a '77? I dont have an air pump and removed the A/C compressor, so with that setup I think the alternator is on the pass. side and P/S on drivers side, but Im having a real hard time finding the V-belts. After looking at comp cams I found the Xtreme Energy cam kit that fits well with the stock motor/torque converter, and has a rough idle.
http://www.summitracing.com/parts/cca-k11-242-3
That and new main/rod bearings and rings for peace of mind, and I think Ill be ready to put it in.
http://www.summitracing.com/parts/cca-k11-242-3
That and new main/rod bearings and rings for peace of mind, and I think Ill be ready to put it in.
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
So far Ive ordered the BBC long water pump pulleys and a set of shorty headers. Am I correct in assuming that if they fit a '73 with a big block it should fit fine in a '77? I dont have an air pump and removed the A/C compressor, so with that setup I think the alternator is on the pass. side and P/S on drivers side, but Im having a real hard time finding the V-belts. After looking at comp cams I found the Xtreme Energy cam kit that fits well with the stock motor/torque converter, and has a rough idle.
http://www.summitracing.com/parts/cca-k11-242-3
That and new main/rod bearings and rings for peace of mind, and I think Ill be ready to put it in.
http://www.summitracing.com/parts/cca-k11-242-3
That and new main/rod bearings and rings for peace of mind, and I think Ill be ready to put it in.
You can't just replace the rings without prepping the cylinders.
Drifting
Joined: Jan 2011
Posts: 1,853
Likes: 81
From: Hamilton Virginia
So far Ive ordered the BBC long water pump pulleys and a set of shorty headers. Am I correct in assuming that if they fit a '73 with a big block it should fit fine in a '77? I dont have an air pump and removed the A/C compressor, so with that setup I think the alternator is on the pass. side and P/S on drivers side, but Im having a real hard time finding the V-belts. After looking at comp cams I found the Xtreme Energy cam kit that fits well with the stock motor/torque converter, and has a rough idle.
http://www.summitracing.com/parts/cca-k11-242-3
That and new main/rod bearings and rings for peace of mind, and I think Ill be ready to put it in.
http://www.summitracing.com/parts/cca-k11-242-3
That and new main/rod bearings and rings for peace of mind, and I think Ill be ready to put it in.
Last edited by scrappy76; Jan 22, 2015 at 09:26 AM. Reason: add