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I'm planning on swapping my 307 to a 454. This process will take me prob 2- 3yrs and I'm planning on swapping the engine last. My question to you all since I'll have to completely change everything in my car to support the 454 ,from my current 307 stock setup . Is what would be the correct order in doing things? Forgot to mention my ultimate goal is to have 600hp .
 

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I'm planning on swapping my 307 to a 454. This process will take me prob 2- 3yrs and I'm planning on swapping the engine last. My question to you all since I'll have to completely change everything in my car to support the 454 ,from my current 307 stock setup . Is what would be the correct order in doing things? Forgot to mention my ultimate goal is to have 600hp .
Never had a project like this.. i just can tell you to achieve 600hp from a 454 you reach this goal the most cost effective way with some treated 049/781 heads (2.19/1.88 valves) or just directly go with some aftermarket heads.. and i would go with a dual plane. With 781/049s probably with an air-gap rpm. With alloy heads maybe with non-air gap rpm... & hyd. roller cam of course..

here are two good articles:

Rectangle Vs. Oval Port Big-Block Head Test - Car Craft Magazine

Big-Block Heads Shootout - The Big O Vs. The Big R - Super Chevy Magazine
 

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To create a proper list, there are a few questions. Do you plan on changing out parts as you drive the car for that 2-3yrs? Are you going to just buy the parts and store them until the swap, so you need the order of steps then? Are you also changing out the Trans and Rear-end (or just the Gearing)? What do you have now for those? What percentage of HWY and City driving? How far do you want the list to cover? Just the Swap on the front end parts or the entire car/suspension to use 600hp?

Mike
 

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Get your suspension and brakes in order first if you haven't already done that yet. What rear end does your car have now? If your car has a 10-bolt, you'll probably want to think about upgrading to a different rear end.

Stuff like your cooling system, your transmission (will you be keeping your current transmission or swapping this out too?), possibly your driveshaft depending on your transmission choice, your exhaust, and all the other odds and ends should be done when you do the swap. There's no point in doing any of that until your 454 is ready to go in.
 

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Just for the engine change issues ONLY, it will more or less be a direct swap.
Remember, Chevelles were built for, and came with a big block.
Now, with that said, NOTHING, NOTHING, NOTHING interchanges between a small block and a big block------------------except maybe the oil in the pan.
You need all the accessory items for a BB, starting with the engine frame mounts, pulleys, exhaust manifolds (or headers), air cond brackets, alternator brackets, PS pump brackets, etc, etc, etc, NOTHING from the 307 will fit the 454.
Then, you go from there. Suspension, brakes, replace the 10bolt with a 12bolt, stronger transmission, etc.
 

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Just for the engine change issues ONLY, it will more or less be a direct swap.
Remember, Chevelles were built for, and came with a big block.
Now, with that said, NOTHING, NOTHING, NOTHING interchanges between a small block and a big block------------------except maybe the oil in the pan.
You need all the accessory items for a BB, starting with the engine frame mounts, pulleys, exhaust manifolds (or headers), air cond brackets, alternator brackets, PS pump brackets, etc, etc, etc, NOTHING from the 307 will fit the 454.
Then, you go from there. Suspension, brakes, replace the 10bolt with a 12bolt, stronger transmission, etc.
One thing will work between the 307 and the 454. You can keep the same engine stands and mounts and save yourself the hassle of having to change the stands on the frame.

Keep the 307 engine stands on the frame and you can use 307 engine mounts on the 454 (I recommend the polyurethane ones.) If you swap the stands on the frame, you will have to swap the mounts on the engine.

But, using a 307 engine stand and 307 engine mount will keep the engine in the same place as a 454 engine stand and 454 engine mount. 307 engine stands/mounts are tall/skinny. non-307 engine stands/mounts are short/fat. I've still never heard a good reason on why the 307 got a special set of engine stands/mounts.
 

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One thing will work between the 307 and the 454. You can keep the same engine stands and mounts and save yourself the hassle of having to change the stands on the frame.

Keep the 307 engine stands on the frame and you can use 307 engine mounts on the 454 (I recommend the polyurethane ones.) If you swap the stands on the frame, you will have to swap the mounts on the engine.

But, using a 307 engine stand and 307 engine mount will keep the engine in the same place as a 454 engine stand and 454 engine mount. 307 engine stands/mounts are tall/skinny. non-307 engine stands/mounts are short/fat. I've still never heard a good reason on why the 307 got a special set of engine stands/mounts.
WHOA - heads up! The 307 frame mounts/stands will work, but they are NOT the same as those for a 454. All 6 cylinder and 307 frame mounts are taller than those used for all other small blocks and big blocks - those mounts are actually lower.

Why did GM do that? I've never heard the reasoning.

Personally, I've used the taller frame mounts (307 mounts) with no problem on a big block - no issues. As far as I know, the engine mounts are all the same fitment between 307 and all other small/big blocks - but don't quote me on that! Looking at Energy Suspension, it appears they only sell one part number for both small and big block Chevelles.

Just a heads up the factory frame mounts are not all the same.
 

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Used the same on a Chevelle no issues. Tried it on a 68 Camaro several months ago with the stock hood and it didn't work as in too high. Though I prefer a Poly mount on one side and solid on the other.

Mike
 
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WHOA - heads up! The 307 frame mounts/stands will work, but they are NOT the same as those for a 454. All 6 cylinder and 307 frame mounts are taller than those used for all other small blocks and big blocks - those mounts are actually lower.

Why did GM do that? I've never heard the reasoning.

Personally, I've used the taller (307 mounts) with no problem on a big block - no issues.

Just a heads up they are NOT the same.
Correct, and I never said they were the same.

Use the 307 frame stand and the 307 engine mount and you are good. Use the non-307 frame stand and the non-307 engine mount and you are good. Try to intermix the 307 frame stand and non-307 engine mount, or the non-307 frame stand and 307 engine mount and you are not good.

So, since the OP has a 307 frame stand, he should simply use the 307 engine mount on his 454 and he will be good.
 

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Planning on 600 HP you want the correct engine mount frame stands and motor mounts for a BBC, IIRC they have a locking type deal in case the mount breaks, I used Energy Suspension mounts every where possible, and while the engine is out of your way do all your front suspension, brake lines that run under the engine if you need to change this is the best time, new brakes, radiator, all this was probably already said but why 2-3 yrs? :unsure: unless you're doing other stuff too? mines been going on 12 yrs. ? LOL
 

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Planning on 600 HP you want the correct engine mount frame stands and motor mounts for a BBC, IIRC they have a locking type deal in case the mount breaks, I used Energy Suspension mounts every where possible
Yup. And they make the 307 style engine mounts with the safe interlocking now which is why I recommended the polyurethane ones as they are interlocking.
 

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I did the same swap on a 71 Nova (307 to 454) in a weekend, then changed the other pieces as I went along. Easy swap. Nothing needed suspension wise except big block springs. I even kept the TH350, which handled the extra power just fine.

And just to mess with Tom a little bit :) a 307 and a 454 do/can use the same distributor and the same starter, and possibly a couple of the same pulleys.
 

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Not trying to bust anyone's balls, but would there be any valid reason the keep the 50+ year old 307 mounts in a swap like this? The cost of new mounts and frame stands is a drop in the bucket considering everything else that would need to be done here. If it were me, big block frame stands and new mounts would be a given.
 
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I didn't know about the 307 locking mounts, the 307 stands are taller IIRC so would that put the engine closer to the hood?, my Malibu was a 307 PG car and had those stands but I replaced them for fear of motor mount breaking and height
 

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I kept the 307 frame stands, and used new 307 mounts when I did my swap. My 454 however was only very slightly modified from stock, nowhere near 600hp. The poly mounts are likely best for the OP's needs.

This was in my "broke-ass college kid" days. I used the 307 clutch fan also - bolted right to the 454 water pump.
 
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What type of driving do you plan on doing that you need 600HP? What is your budget to do it right, upgrading most all components. I had the same delima a few years back and I sold the SB car and bought a SS BB car, almost an even trade. My Vette has 400HP that I never have a need for. . . . . . . .just an old guy talkin that has been there done that.
 

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I didn't know about the 307 locking mounts, the 307 stands are taller IIRC so would that put the engine closer to the hood?, my Malibu was a 307 PG car and had those stands but I replaced them for fear of motor mount breaking and height
No, the 307 frame stands are taller, but the engine mounts are shorter. The engine winds up in the same place.

Still haven't heard a good reason for why the 307 had tall frame stands and short engine mounts, but all other V8 engines had short frame stand and taller engine mount.

shrug

(Also, this only applies to the Chevelle - other cars like Camaro or Nova, they did different things so your results may vary on those...)
 

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Not trying to bust anyone's balls, but would there be any valid reason the keep the 50+ year old 307 mounts in a swap like this? The cost of new mounts and frame stands is a drop in the bucket considering everything else that would need to be done here. If it were me, big block frame stands and new mounts would be a given.
I agree, toss the 50 year old 307 engine mounts and get new ones. But, why replace the frame stands if they are in good shape? If it were a 350 swap to a 454, I wouldn't replace the frame stands there either if they were in good shape, especially as the 350 and 454 used the same frame stand. I would replace the engine mounts though.

Edit: Added the link to the two engine mounts.


 

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Don't forget the 3 inch exhaust all the way back, maybe upgrade the 1310 U joints you have there, turbo 400 if going auto, 12 bolt like they said above, how about some cooling upgrades, disc brakes would be good especially if you have front drums. The problem with some of these big leap engine upgrades is the ancillary stuff is just as expensive as the motor.
 

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And if you put a fun cam in there don't forget about a fun torque convertor and better wheel studs in the upgraded axels, BTDT ;)
 
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