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[C2] Engine number help

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Old Dec 29, 2017 | 10:05 AM
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Default Engine number help

Gents

Looking at a 67 327 with NOM. Production date is Dec 28,1966

Block is 3858174 Stamped F0429YS and heads are D286 3917291

Seller states 350HP but I am confused because the thermostat housing is the 300HP style not the larger L79 housing. Aluminum manifold with temp sensor on passenger side of housing looks right.

My question is how can I determine if 300 or 350 HP

Randy

Last edited by 66RBS; Dec 29, 2017 at 12:27 PM. Reason: Added last sentence
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Old Dec 29, 2017 | 01:50 PM
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Originally Posted by 66RBS
Gents

Looking at a 67 327 with NOM. Production date is Dec 28,1966

Block is 3858174 Stamped F0429YS and heads are D286 3917291

Seller states 350HP but I am confused because the thermostat housing is the 300HP style not the larger L79 housing. Aluminum manifold with temp sensor on passenger side of housing looks right.

My question is how can I determine if 300 or 350 HP

Randy
The thermostat housing could have been changed. A lot can happen in 50 years. IF the engine is basically untampered with look at the balancer and the carb. Other than that if I remember correctly I think all other things are internal such as pistons and cam.

Last edited by 68hemi; Dec 29, 2017 at 01:51 PM.
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Old Dec 29, 2017 | 02:46 PM
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3858174 = 1964-67 327, F0429YS = 1966 220HP 327, C-10 to C- 35 truck.
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Old Dec 29, 2017 | 03:21 PM
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Originally Posted by 1snake
3858174 = 1964-67 327, F0429YS = 1966 220HP 327, C-10 to C- 35 truck.
The Op stated it is a NOM car, it sounds to me like the seller is saying the engine in the car is supposed to be built to 350 h.p. specs.
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Old Dec 29, 2017 | 07:11 PM
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Originally Posted by 68hemi
The thermostat housing could have been changed. A lot can happen in 50 years. IF the engine is basically untampered with look at the balancer and the carb. Other than that if I remember correctly I think all other things are internal such as pistons and cam.
So are there different diameters and or thickness balancer for 300HP vs. 350HP?
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Old Dec 29, 2017 | 07:18 PM
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Originally Posted by 66RBS
So are there different diameters and or thickness balancer for 300HP vs. 350HP?
Yes. The 300 got the 6” and 350 got a 8”
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Old Dec 29, 2017 | 07:19 PM
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Originally Posted by 66RBS
So are there different diameters and or thickness balancer for 300HP vs. 350HP?
I believe the 300 h.p. used a 6 3/4" and the 350/365/375 h.p. used an 8". If I am wrong certainly someone here will correct me.

Last edited by 68hemi; Jan 1, 2018 at 11:52 PM.
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Old Dec 29, 2017 | 07:40 PM
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I would say that if you know it is a non original motor car, to not be too concerned with these details as it does not add or take away from the cars value. Does it feel like it has good power & sound good, go for it. That value has been lost with the original motor, so make sure the price of the car reflects that loss of value.

With that said, consiter the motor a blank canvas, what horsepower would you like it to have, because you have the freedom to build it to what you want it to be, without worrying about originality & there is a certian freedom in that, a freedom you dont have if it was an original motor car.
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Old Dec 29, 2017 | 07:51 PM
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Originally Posted by 66RBS

My question is how can I determine if 300 or 350 HP

Randy
Again, that engine started life as a 220HP truck engine. What it is now is anyone's guess. What the seller is telling you can only be proven by a complete dis-assembly.
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