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96DXCivic
96DXCivic HalfDork
2/17/10 7:14 p.m.

What makes the 350 a better performance engine then the 305 engine other then the bigger displacement?

Stealthtercel
Stealthtercel Reader
2/17/10 7:18 p.m.

I believe some 305s got less robust internal parts, but I think it's mostly just displacement. Car Craft is your uber-source for this recurring debate.

SkinnyG
SkinnyG Reader
2/17/10 7:29 p.m.

A larger bore allows larger valves or at least less valve shrouding.

96DXCivic
96DXCivic HalfDork
2/17/10 7:32 p.m.

So what kinda power can a 305 get?

belteshazzar
belteshazzar SuperDork
2/17/10 7:35 p.m.

not enough

ncjay
ncjay Reader
2/17/10 7:42 p.m.

Like many Chevy engines, there are crap parts and decent high performance parts from the factory. Year of manufacture has much to do with it. In general, early 80s 305 head are crap compared to a 350 head. It helps to be able to identify the different heads to know the good from the bad. Nearly everything else is identical from 305 to 350.

Spinout007
Spinout007 GRM+ Memberand HalfDork
2/17/10 7:45 p.m.

If you're looking for uber easy power, go with a 350 if you're looking for something different,and a big pain to get decent power out of, go with the 305.

neon4891
neon4891 SuperDork
2/17/10 7:49 p.m.

Smaller bore KILLS the air flow. I have seen this debate way too many time(I subscribe to CC). The only use for a 305 is if it came stock in your vehicle of choise and you are running it till it dies or have your built 350(or whatever) ready to install. This goes for ANY and ALL sub 4" bore 1st gen SBCs.

Raze
Raze Reader
2/17/10 8:16 p.m.

I think the 305/350 debate comes up once a year, starts off slow and after a day blows wide open, and a day later dies, because as exciting as it 'might' be, i'd say this group is liberal in our car 'thoughts' but conservative in deed, we would all love to drive a TVR to be different, but for practicality's sake we end up with a Miata...

pres589
pres589 Reader
2/17/10 8:31 p.m.
96DXCivic wrote: What makes the 350 a better performance engine then the 305 engine other then the bigger displacement?

Is it just me, or does this get asked about once a month here?

Woody
Woody GRM+ Memberand SuperDork
2/17/10 8:37 p.m.
Raze wrote: We would all love to drive a TVR to be different, but for practicality's sake we end up with a Miata...

That's a fairly profound observation right there.

96DXCivic
96DXCivic HalfDork
2/17/10 9:05 p.m.

I was just wondering because I have seen a bunch really cheap. How much power can you get with a intake manifold and 4 barrel swap plus header?

petegossett
petegossett GRM+ Memberand SuperDork
2/17/10 9:13 p.m.
Woody wrote:
Raze wrote: We would all love to drive a TVR to be different, but for practicality's sake we end up with a Miata...
That's a fairly profound observation right there.

...and describes me to a T.

FWIW I have a 305 TBI in my 88 1/2-ton and it's a total dog. Seriously, 0-60 must be ~15-seconds, and I can't blame it on age or mileage, as the drivetrain only has 30k on it.

patgizz
patgizz GRM+ Memberand SuperDork
2/17/10 9:23 p.m.

as cheap as you can find a 305, you can find a 350 for the same price if you look.

small bore limits valve size that limits airflow that takes less advantage of breathing mods and it all stacks up from there.

great appliance engine, i've had several over 220k miles. they run forever even when i try to kill them.

Appleseed
Appleseed Dork
2/18/10 12:18 a.m.

Like everyone else said, bad performance engine. great appliance engine. We had one snap a crank on an angle between #2 and #3 mains. Locked it together in such a way that we were able to drive it for 6 days while we dug us up another crank.

914Driver
914Driver SuperDork
2/18/10 6:53 a.m.

Wheels 777 gave me some tips on how to make real power with a 305, you might want to contact him.

Dan

Gimp
Gimp GRM+ Memberand Dork
2/18/10 8:11 a.m.
914Driver wrote: Wheels 777 gave me some tips on how to make real power with a 305, you might want to contact him. Dan

What's "real power"?

zomby woof
zomby woof HalfDork
2/18/10 9:02 a.m.

There are some circle track classes up here that run 305's, and they find a way to make them work. The valves are smaller. I'm not sure about the late model stuff, but the better 80's heads had a 1.84 intake/1.5 exhaust, and those motors went OK. It's no 350, but if you're not looking to make big power, then the 305 will work, especially in a light application.

itsarebuild
itsarebuild GRM+ Memberand New Reader
2/18/10 9:56 a.m.

i remember reading an old car craft article where they got 280 HP out of a 305 but it was at the edge of being streetable. that was before vortec heads though so there may be more potential. i'm with the rest of the group though when they say a 350 is worth the extra money. (which usually is couple hundred dollars at best)

njansenv
njansenv Reader
2/18/10 11:05 a.m.

With the LS1 and variants around, the "old" 350's are pretty darn cheap. I hear great things about the "Vortec" 350 found in the mid-late 90's Chevy trucks.
Word is the heads flow quite well...

Nathan

EricM
EricM Dork
2/18/10 11:45 a.m.

like mentioned earlier, a 350 with the Vortec heads and a few other tweeks and you can't go wrong.

305 Suitable for anchoring a boat.

Raze
Raze Reader
2/18/10 11:54 a.m.
EricM wrote: ...305 Suitable for anchoring a boat.

I resent that, my yacht is not a 'boat'...

Gearheadotaku
Gearheadotaku GRM+ Memberand HalfDork
2/18/10 5:15 p.m.

It's all about what you have, what you want to do, and how much you're willing to spend. Early 90's TPI 305 w/the G92 cam went pretty good. 230HP and 300lbs. The TPI 350 was 245 HP and 345 lbs, so not much different. Add the fact that 305's had a 5-speed and 3.42 gear vs. auto and 2.73, it came down to the better driver.

iceracer
iceracer HalfDork
2/18/10 5:47 p.m.

Didn't some of the IROC's have 305's ?

DILYSI Dave
DILYSI Dave SuperDork
2/18/10 6:25 p.m.
iceracer wrote: Didn't some of the IROC's have 305's ?

Mine did. 1985 IROC with the 5.0 HO. Electronic quadrajet topping 165 horses of daisy-pulling power...

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