327 or 350? Which should I get
Thread Starter
Junior Member
Joined: Aug 2004
Posts: 70
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From: New Berlin, WI
Car: 91 Pontiac Firebird
Engine: 305 soon 350
Transmission: T5
327 or 350? Which should I get
Okay, I have a 305 TBI and I will be using the TBI on the new motor. I have a choice between two motors, a 327 and a 350.
350 Includes
-Rebuilt Heads
-65,xxx-75,xxx miles on block
327 Includes
-Rebuilt Heads
-Bored .20 over just enough to clean the cylinder wall
-New Pistons
-Reground Cam, and Crank
Some other stuff but can't think right now.
What would I be better off doing for power wise high and low end power. I hear different things about the two motors but I don't know what's true and what's not, so some one fill me in.
Thanks,
Dan
350 Includes
-Rebuilt Heads
-65,xxx-75,xxx miles on block
327 Includes
-Rebuilt Heads
-Bored .20 over just enough to clean the cylinder wall
-New Pistons
-Reground Cam, and Crank
Some other stuff but can't think right now.
What would I be better off doing for power wise high and low end power. I hear different things about the two motors but I don't know what's true and what's not, so some one fill me in.
Thanks,
Dan
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From: Gardnerville, Nv.
Car: 00 Camaro SS
Engine: 5.7
Transmission: 6 speed
327's are good high reving motors.It just depends on what it'll be used for.My uncle runs 327's on an oval track.If your using it for street then I would stick with the 350.
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Joined: Jul 2003
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From: Grand Rapids, MI
Car: Z28
Engine: Sb2.2 406
Transmission: Jerico 4 speed
Axle/Gears: Ford 9" 3.60
350.
-De-cubing is only good for when you run something where cubes are limited.
-More cubes = more power.
-revving has very little to do with this as either way TBI heads are being used.
Aside from the less than obvious, there's the obvious. You can't grind a crank with a 3.48" stroke (350 crank) down to a 3.25" stroke (327 crank).
And just to make sure, not trying to insult your intelligence, but unless you have a different block, you can't make a 4.0xx bore out of a 3.7xx bore.
-De-cubing is only good for when you run something where cubes are limited.
-More cubes = more power.
-revving has very little to do with this as either way TBI heads are being used.
Aside from the less than obvious, there's the obvious. You can't grind a crank with a 3.48" stroke (350 crank) down to a 3.25" stroke (327 crank).
And just to make sure, not trying to insult your intelligence, but unless you have a different block, you can't make a 4.0xx bore out of a 3.7xx bore.
Last edited by Stekman; Sep 8, 2004 at 01:47 AM.
Joined: Mar 2000
Posts: 43,187
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Inadequate data.
If the choice you make now is what you are going to run forever, with no other changes allowed, it's impossible to know which is the better engine. There were simply too many 327's and 350's made with so many different combinations that it's impossible to say which is better. It is altogether possible the 327 will make more power, depending upon which heads and cam each has.
However...
If this isn't necessarily the final destination, the 350 is the only choice. Cam & heads are fairly simple to change out.
If the choice you make now is what you are going to run forever, with no other changes allowed, it's impossible to know which is the better engine. There were simply too many 327's and 350's made with so many different combinations that it's impossible to say which is better. It is altogether possible the 327 will make more power, depending upon which heads and cam each has.
However...
If this isn't necessarily the final destination, the 350 is the only choice. Cam & heads are fairly simple to change out.
Junior Member
Joined: Apr 2004
Posts: 36
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From: Pittsburgh, PA
Car: 1987 Z28
Engine: 305 TPI
Transmission: 700R4
Its a good battle
I'd say if its an automatic car - Definate 350
If its a 5-speed (or 6) - 327 For sure
If the car is geared right, both motors would rock.
At this point, its personal taste.
I went the complete opposite route, I'm building a 302 for my 85 Z28. If its gonna be a 5.0L, why not make it badass?
Just my $.02
Good luck either way, better than a 305.
I'd say if its an automatic car - Definate 350
If its a 5-speed (or 6) - 327 For sure
If the car is geared right, both motors would rock.
At this point, its personal taste.
I went the complete opposite route, I'm building a 302 for my 85 Z28. If its gonna be a 5.0L, why not make it badass?
Just my $.02
Good luck either way, better than a 305.
Thread Starter
Junior Member
Joined: Aug 2004
Posts: 70
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From: New Berlin, WI
Car: 91 Pontiac Firebird
Engine: 305 soon 350
Transmission: T5
It is a 5 spd, but I have the stock rear end one wheel wonder, but I might be getting a 3:73 posi rear end. How would this work and would you still say get the 327?
Thanks,
Dan
Thanks,
Dan
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Thread Starter
Junior Member
Joined: Aug 2004
Posts: 70
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From: New Berlin, WI
Car: 91 Pontiac Firebird
Engine: 305 soon 350
Transmission: T5
He's asking 250, I guess he got the motor in a trade or something, he has some 455's laying around too which he would take 600 for but I dont wana go that high..
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Joined: Apr 2004
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From: Pittsburgh, PA
Car: 1987 Z28
Engine: 305 TPI
Transmission: 700R4
Nice thing about the 327 is that is doesn't produce as much torque as the 350 does. Its a great benifit to those who don't have a WC (World Class) T5. I'm more of a short stroke fan, though that could be a neverending arguement (along with the difference of EFI over a Carb).
A 327 powered 3rd gen isn't the typical either, gets tiresome seeing that damn near EVERYONE has a 350 in their car. Give the competition something different.

But yes, I'd jump all over the 327 for a 5-speed car. A warmed over 327 would wake up that car. Being me (crazy, right?), I'd put a mild cam in the 327, bolt it up and call it a day.
I agree with the idea of putting the 350 on the side as project motor, but then you could always destroke the 350
A 327 powered 3rd gen isn't the typical either, gets tiresome seeing that damn near EVERYONE has a 350 in their car. Give the competition something different.

But yes, I'd jump all over the 327 for a 5-speed car. A warmed over 327 would wake up that car. Being me (crazy, right?), I'd put a mild cam in the 327, bolt it up and call it a day.
I agree with the idea of putting the 350 on the side as project motor, but then you could always destroke the 350
Last edited by OneLongProject; Sep 11, 2004 at 02:50 AM.
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From: Saskatoon, SK, Canada
Car: '83 Z28, '07 Charger SRT8
Engine: 454ci, 6.1 Hemi
Transmission: TH350, A5
Axle/Gears: 2.73 posi, 3.06 posi
If they are stock, any 327 motor you find will be a pre-smog motor, whereas almost any carb'd 350 you find will be a smog motor.
Take that as you want
Take that as you want
Joined: Sep 2004
Posts: 2,777
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From: Casselberry, FLA
Car: 88 V6 'bird/89TBI bird/85 T/A
Engine: 2.8/TBI/TPI
Transmission: V8 T-5/700R4 x2
Axle/Gears: 3.42 open/2.73 open/ 3.27 9 bolt
No replacement for displacement!!
68-70 350s are non smog.
68-70 350s are non smog. TGO Supporter

Joined: Apr 2004
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From: Massachusetts
Car: 91 Z28 & 21 Hellcat Challenger
Engine: L98, Hemi 6.2
Originally posted by KrisW
No replacement for displacement!!
68-70 350s are non smog.
No replacement for displacement!!
68-70 350s are non smog. Junior Member
Joined: Apr 2004
Posts: 36
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From: Pittsburgh, PA
Car: 1987 Z28
Engine: 305 TPI
Transmission: 700R4
Actually the powerbands are different.
The 350 would have much more low end torque.
The 327 would have better mid range and upper RPM power.
Both have a 4" bore
350 having the longer stroke (3.48")
327 having a shorter stroke (3.25")
Its like comparing a 350 Chevy to a 383.
Different strokes.
The downside to the 327 is that it doesn't have as much grunt off the line.
Once it gets going, thats another story.
Thats just my
The 350 would have much more low end torque.
The 327 would have better mid range and upper RPM power.
Both have a 4" bore
350 having the longer stroke (3.48")
327 having a shorter stroke (3.25")
Its like comparing a 350 Chevy to a 383.
Different strokes.
The downside to the 327 is that it doesn't have as much grunt off the line.
Once it gets going, thats another story.
Thats just my
Thread Starter
Junior Member
Joined: Aug 2004
Posts: 70
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From: New Berlin, WI
Car: 91 Pontiac Firebird
Engine: 305 soon 350
Transmission: T5
Okay, I might have a 350 crate motor with 15,000 miles on it. It is a 480 or 580 horse motor, but I'm kinda scared on putting it in my car. The guy said he could reinforce the frames by welding in square beams blah blah, and as far as the rear end I'm scared for that I have the stock one wheel wonder so I don't know what to put in it. As far as the tranny I have the second edittion T5, I guess it's supposd to be stronger than the older T5's before 1990. So my questions to all the smart people on here
is what would i Have to do to keep this car running and get as much power as possible without turning my car into a tin can.
Thanks Guys,
Dan
is what would i Have to do to keep this car running and get as much power as possible without turning my car into a tin can.Thanks Guys,
Dan
Actually the powerbands are different.
The 350 would have much more low end torque.
The 327 would have better mid range and upper RPM power.
The 350 would have much more low end torque.
The 327 would have better mid range and upper RPM power.
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From: Carson, CA
Car: '88 GTA, 90 Formula
Engine: 5.7 TPI, fed growth hormones
Transmission: 700r4 4u2?
Axle/Gears: 9bolt
You guys are mostly generalizing, but there is not enough information here. Which heads do the respective engines have? Will the 327 run on modern pump gas? What application and year is the reground cam from? Are these PU truck engines, or Corvette engines that are rebuilt? Huge differences between the two.
If both are comprable applications, the 350 would have the edge just by displacement, but not by much. If the 327 is a Hi Po motor and the 350 is not, obviously the 327 is the way to go. Check the heads for casting numbers so you know what you're getting. There were a LOT of different tuning and head combos on both engines that would easily make differences of over 100 HP per application. You need more info.
Do either come with a manual trans, or any type of flywheel?
Troy
So Cal
If both are comprable applications, the 350 would have the edge just by displacement, but not by much. If the 327 is a Hi Po motor and the 350 is not, obviously the 327 is the way to go. Check the heads for casting numbers so you know what you're getting. There were a LOT of different tuning and head combos on both engines that would easily make differences of over 100 HP per application. You need more info.
Do either come with a manual trans, or any type of flywheel?
Troy
So Cal
There were a LOT of different tuning and head combos on both engines that would easily make differences of over 100 HP per application
Senior Member
Joined: Dec 2000
Posts: 640
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From: El Paso Texas
Car: 86 z28
Engine: Hyd. roller 498
Transmission: 700r4
Axle/Gears: 12 bolt 3.90 gears
Also keep in mind that a high revvin engine will require expensive parts to prevent catastrophic failure.
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