Opinions on swapping out original 327 350 with crate big block on a 67 coupe.
11-25-2018, 12:10 PM
#1
Racer
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Opinions on swapping out original 327 350 with crate big block on a 67 coupe.
I have an original 327 350 #'s matching in my 67. Thinking of swapping out for a crate big block. Would appreciate any help on what size motor, if it makes sense, how it would affect value etc. Thanks.
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11-25-2018, 08:37 PM
Le Mans Master
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Well, I was gonna stay out of this.................................and I probably should.........................but here goes anyway. I have a matching number 67 coupe, 327-350 engine, 4 speed. I purchased the car in 2006 and enjoyed it for a couple years as a nice small block driver. I had always wanted a big block Corvette so in 2008 I decided to go all out and build an L-88 tribute car. I found a new ZL-1 aluminum block and all new GM components (heads, crank, rods, pistons) for about the same money, and probably a little less than what I would spend on the iron block and 67 aluminum heads.
Everything was a direct bolt in and I have the power of a big block with the weight of a small block. I kept every piece, every nut and bolt I removed in the conversion and it could easily be converted back to a 100% matching number car in a few days. Ten years later and I have no regrets in making the change and I don't feel it devalued my car in any way. I know some may disagree and I appreciate and respect your philosophy on this topic. I'm not getting any younger and I have enjoyed the car since I made the conversion. I'm not a "show circuit" kinda guy but I appreciate those who are. To each his own.
I guess my point is / was.................................it's your car. Enjoy it the best way you can.
Thanks,
Rex
Everything was a direct bolt in and I have the power of a big block with the weight of a small block. I kept every piece, every nut and bolt I removed in the conversion and it could easily be converted back to a 100% matching number car in a few days. Ten years later and I have no regrets in making the change and I don't feel it devalued my car in any way. I know some may disagree and I appreciate and respect your philosophy on this topic. I'm not getting any younger and I have enjoyed the car since I made the conversion. I'm not a "show circuit" kinda guy but I appreciate those who are. To each his own.
I guess my point is / was.................................it's your car. Enjoy it the best way you can.
Thanks,
Rex
11-25-2018, 12:18 PM
#2
Le Mans Master
Will detract from value in my opinion. 327/350 HP was a very well balanced engine package and desirable in a 67. Why are you thinking of the change out if I may ask?
11-25-2018, 12:21 PM
#3
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Buy a car with a BB in it if that's what you want. You'll pay a premium for then engine and parts to install and lose another premium in loss of value to the car.
11-25-2018, 12:31 PM
#4
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If it were my car and I wanted more power I would stroke the original engine. This will do two things, replaced the standard/weak rods the GM used and give you the added cubic inches of the stroked engine. I would balance and blue print the engine and add aluminum heads. The aluminum heads will allow for lower octane gas to be used with yours 11 to 1 compression. With the above things done you should have a pretty bulletproof engine that is still the original matching numbers.
11-25-2018, 12:51 PM
#5
I had a '66 Convertible, with PB that had an engine swap from a 327 to a 502 BB.
Mechanically it didn't take too much for the SB to BB engine swap (Radiator, Engine, Bell Housing, Clutch, Electric "Fuel Pump, Distributor for Mechanical Tach and exhaust. The Trans and Differential were strong enough for the 500 HP & Ft/Lb of torque (before 50 years of use). There were no modifications that could not be undone.
The 502 was reliable and fun in the '66, but I found the added clutch force due to the high HP/Torque was a negative, but I think you could go with a hydraulic clutch that would reduce effort. It also had 3" side pipes so the BB could breath, and the noise would rattle your fillings, so there was a lot of Wow when I started it up and ear plugs when I drove it.
I would say the car with the original 327 would have been a 45K-50K car, and I sold it for the same money with the BB 502.
If your car is paid for and you want to swap out the engine, do it.
Phil
Mechanically it didn't take too much for the SB to BB engine swap (Radiator, Engine, Bell Housing, Clutch, Electric "Fuel Pump, Distributor for Mechanical Tach and exhaust. The Trans and Differential were strong enough for the 500 HP & Ft/Lb of torque (before 50 years of use). There were no modifications that could not be undone.
The 502 was reliable and fun in the '66, but I found the added clutch force due to the high HP/Torque was a negative, but I think you could go with a hydraulic clutch that would reduce effort. It also had 3" side pipes so the BB could breath, and the noise would rattle your fillings, so there was a lot of Wow when I started it up and ear plugs when I drove it.
I would say the car with the original 327 would have been a 45K-50K car, and I sold it for the same money with the BB 502.
If your car is paid for and you want to swap out the engine, do it.
Phil
Last edited by 856666; 11-25-2018 at 01:01 PM.
11-25-2018, 01:26 PM
#6
Le Mans Master
If you do Swap I believe there is a difference in motor mounts that is often overlooked. Check it out. Hood clearence also ???
Last edited by Vette5311; 11-25-2018 at 01:27 PM.
11-25-2018, 01:34 PM
#7
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seems like a mistake. sell your car and buy one of the many NOM BB cars out there for sale
11-25-2018, 01:47 PM
#8
Yes and Yes to engine mounts and hood clearance - I had a 65/66 BB hood and needed the extra room for the air cleaner
A set of Headers too!!!
Phil
A set of Headers too!!!
Phil
Last edited by 856666; 11-25-2018 at 03:14 PM.
11-25-2018, 01:56 PM
#9
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It would make a nice car a car that would not appeal to me at all, and it would decrease the value by a bunch. If you want more power, mothball the original engine and install a crate small block with 500 HP. Then prepare to upgrade everything else on the car to match the power. If your current car bugs you, sell it to someone who would appreciate it (there are a lot of us out here) and buy a big block car that is real or fake, whatever. I personally MUCH prefer the small block Sting Rays over the big block cars...much better cars to actually drive.
11-25-2018, 02:58 PM
#10
Another reason to keep the existing car and change the engine and updating the components (keeping the original units) is the existing car has family linkage, and or is well sorted out and familiar. Selling it and purchasing another vehicle is a hassle the owner my not want to experience, and means the owner would have to start all over, lots of unknowns.
11-25-2018, 03:08 PM
#11
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If it were my car and I wanted more power I would stroke the original engine. This will do two things, replaced the standard/weak rods the GM used and give you the added cubic inches of the stroked engine. I would balance and blue print the engine and add aluminum heads. The aluminum heads will allow for lower octane gas to be used with yours 11 to 1 compression. With the above things done you should have a pretty bulletproof engine that is still the original matching numbers.
Last edited by 68hemi; 11-25-2018 at 03:11 PM.
11-25-2018, 05:25 PM
#12
Advanced
Matching numbers vs nom always detracts value, how much you’ll lose depends on how much money you put in the swap.
I think the 327 is big enough, more so if it is the 350hp engine in a fiberglass two seater.
I myself have been a victim of “bigger is better” more than a couple of times, you’d think by now I should know better but I always seem to find an excuse to go big again only to regret it later.
There are many reasons to regret it, but to me it is mainly: better handling, easier to enjoy on a longer drive, cleaner looking engine bay, better mileage and the most important easier to work on.
I think it would be unreasonable to swap. Maybe just do some mods to improve on the original engine?
I think the 327 is big enough, more so if it is the 350hp engine in a fiberglass two seater.
I myself have been a victim of “bigger is better” more than a couple of times, you’d think by now I should know better but I always seem to find an excuse to go big again only to regret it later.
There are many reasons to regret it, but to me it is mainly: better handling, easier to enjoy on a longer drive, cleaner looking engine bay, better mileage and the most important easier to work on.
I think it would be unreasonable to swap. Maybe just do some mods to improve on the original engine?
11-25-2018, 06:10 PM
#13
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I'm on the other side of the fence. I'd say go for it. You can always switch back, there are no permanent changes need made. If you go BB , use alum heads ,water pump, and intake that way the weight diff is only about 100#. you will need a BB hood also. Make sure the rest of the drivetrain is up to snuff. Surely not cheap , but a fun project to make a very fun car. You will LOVE the BB torque.
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11-25-2018, 06:19 PM
#15
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a properly tuned L79 with the right rear gear can tare up a BB. so either his is wore out and running like a three legged dog or he is no driver
11-25-2018, 06:25 PM
#16
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It's not as hard of a swap as people like to make it. It will bolt to stock mounts, bellhousing etc. Might have to change flywheel depending on if you use an internal or externally balanced engine. There are many clutches out there like the Centerforce dual friction that can handle the power and have easy pedal effort. No reason for that to change. if you select a block with a fuel pump mount you can just use a mechanical pump for simplicity. I've done it while using the small block radiator and shroud and it worked OK. Or get an aftermarket aluminum one that fits stock core support with more capacity. You can use headers or manifolds....I'd use headers for the power difference. You can juggle brackets without much issue. The stock small block coils will compress a little but not the end of the world. Won't go any lower than a set of 550's will take it anyway. If you decide you want stronger springs they are less than $100 a set. Hood clearance is a tight one so you'll need to handle that and correct intake to make it all work.
One of the best deals going is to get a 496" from VortecPro. He builds incredible engines (I've been to his shop and seen his work as well as seen the results) for great prices. I've sent several people to him and all have been pleased. You'll get better parts and much better performance than a typical mass produced crate engine will supply.
If you decide on a small block...there are quite a few 500+ HP versions based on 400" platforms. I did a 388" for a buddy with some decent heads and solid roller cam quite a few years ago. He flogs it constantly..but it has good forged pistons/crank/rods in it along with aluminum heads. You can idle it away from a light with the Muncie and 3.36's and scream it past 7000 RPM any time you want. I'd prefer an aftermarket block like a Dart or a Blueprint if building a strong one.
But as mentioned...that instant big block torque is a thing of beauty to enjoy!
JIM
One of the best deals going is to get a 496" from VortecPro. He builds incredible engines (I've been to his shop and seen his work as well as seen the results) for great prices. I've sent several people to him and all have been pleased. You'll get better parts and much better performance than a typical mass produced crate engine will supply.
If you decide on a small block...there are quite a few 500+ HP versions based on 400" platforms. I did a 388" for a buddy with some decent heads and solid roller cam quite a few years ago. He flogs it constantly..but it has good forged pistons/crank/rods in it along with aluminum heads. You can idle it away from a light with the Muncie and 3.36's and scream it past 7000 RPM any time you want. I'd prefer an aftermarket block like a Dart or a Blueprint if building a strong one.
But as mentioned...that instant big block torque is a thing of beauty to enjoy!
JIM
11-25-2018, 06:31 PM
#17
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A friend of mine had a dart-block based 427 CID small block done recently for his '68 Camaro. Lighter than the stock 327, and it dyno'ed at 578 HP and 561 foot pounds of torque, all under 6,000 rpm. Not bad for a gen-1 small block.
11-25-2018, 06:31 PM
#18
"I have an original 327 350 #'s matching in my 67. Thinking of swapping out for a crate big block. Would appreciate any help on what size motor, if it makes sense, how it would affect value etc. Thanks."
The OP didn't give a reason for wanting the swap (performance, needs rebuild, etc) or the condition of the L79, so it could these reasons, or he wants a BB and he has the money to fund the swap.
Phil
The OP didn't give a reason for wanting the swap (performance, needs rebuild, etc) or the condition of the L79, so it could these reasons, or he wants a BB and he has the money to fund the swap.
Phil
11-25-2018, 06:58 PM
#20
Melting Slicks
I can't think of a good reason to put a big block in it except possibly bragging rights. If it gets driven much, I would definitely pull the original motor for safe keeping but stay with a small block. You can get all the performance you can use and keep the car better balanced. I pulled my original L79 and built a 500+ HP 406 and love it. There are many options for small blocks and many with warranties.
Last edited by 65air_coupe; 11-25-2018 at 07:01 PM.