What is a 350 bored 0.40 over?

Discussion in 'The Garage' started by CHEVYDADDY, Oct 28, 2008.

Joined:
Sep 12, 2008
Messages:
125
0
Location:
BARDSTOWN KY
a motor yeah i got ya there! wht would it equal or close to what?
i have a short block together needs some cleaning and have heads together need some cleaning wht should i use to clan and how should i go about doing it? wire brush our spary gunk and wip off or even water??

2. Duntz001/2 ton statusPremium MemberGMOTM Winner

Joined:
Jul 22, 2007
Messages:
1,452
1
Location:
Greenup, Ky
358 is a .40 over 350

3. shaun891/2 ton status

Joined:
Aug 7, 2005
Messages:
1,957
1
Location:
center of CT..ish
ya, just some engine degreaser/kerosene/diesel would work good with a wire brush and lots of scrubbing,i would somehow tape or block off the cylinders to keep and the flying crap out of them.

Joined:
Nov 20, 2007
Messages:
9,860
103
Location:
Roseland VA/PtPleasant NJ
I always thought it was a 357?

5. 80' 4271/2 ton statusPremium Member

Joined:
Nov 14, 2006
Messages:
3,902
277
Location:
actually .40 is 423.316
.040 is 356.880

6. 1977k53/4 ton statusVendor

Joined:
May 26, 2003
Messages:
9,844
27
(4.040in/2)^2 * 3.14 = 12.819 in^2

12.819*3.48 = 44.610 in^3

44.610 in^3 * 8 cylinders = 356.88 in^3

7. 4X4HIGH1 ton statusPremium MemberGMOTM Winner

Joined:
Dec 14, 2001
Messages:
21,986
25
Location:
Pleasanton, CA.
Bore x Bore x Storke x .7854 x number of cylinders = CI. 350 .040" over is a 356.88 or 357.

Joined:
Sep 12, 2008
Messages:
125
0
Location:
BARDSTOWN KY
what is suggestable horse power for 357?
can a 350 motor be borad to a 400? how much would it take?

9. buffblazer1/2 ton status

Joined:
Jan 5, 2005
Messages:
2,397
0
Location:
for horsepower its gonna all depend on your set up.

cam
roller or hydro lifters
inkake
carb
serp set up or stock
any emissions

lots of stuff play into how much horsepower your gonna make with a .40 motor

mine is .40 with flat top pistons, stock heads with hydro lifters, comp cams extream 4x4 cam, performer intake and 600cfm edlebrock carb with headers and a regular v belt set up with no emissions. is that similar to what your gonna be running?

Joined:
Sep 12, 2008
Messages:
125
0
Location:
BARDSTOWN KY
yes i traded ariding lawn mower for a short block all together and matching heads i have to clean both but not sure on all details sounds goods

11. 4X4HIGH1 ton statusPremium MemberGMOTM Winner

Joined:
Dec 14, 2001
Messages:
21,986
25
Location:
Pleasanton, CA.
Power is made in the head and cam selection. Most 350's stock put out around 180-210hp.

No, you cannot bore a 350 block out to make a 400. A 400 bore is 4.125".

Joined:
Sep 12, 2008
Messages:
125
0
Location:
BARDSTOWN KY
no emissions
600 cfm
v-belt
heads 626862 (didnt write it down)

Joined:
Sep 12, 2008
Messages:
125
0
Location:
BARDSTOWN KY

14. rob h1/2 ton statusPremium Member

Joined:
Sep 13, 2008
Messages:
1,932
8
Location:
frackville,pa
i took a 74 350 and had it bored .040, decked, maged, line honed, i bought a crane 535 lift cam, comp 1.6 thought 1.7 but no 1.6 roller rockers, domed keithblack pistons 12:1, eagle crank and rods, and bowtie heads with 2.055 stainless valves, comp springs,titanium retainers. melling oil pump, elelbrock rpm airgap intake, holley 750 dp jetted down , holley red fuel pump, all arp bolts, summit 7 qt pan, mallory unilite dist, taylor wires, 1 5/8 primary tubes on headman headers, 3inch ball flanges and 3inch all the way out the back....and ill tell ya its an animal behind my 465 with 456 gears..i have no idea the horsepower range but with 37s i can go 30 and stand on it and burn em off in 3rd gear..

Last edited: Oct 29, 2008
15. Wasatch K51/2 ton status

Joined:
Feb 10, 2008
Messages:
183
0
Location:
Park City, UT
I think the 400 blocks from the factory did not have cooling passages between the cylinders and that's why they could be bored to 4.125.

If you tried that with a 350 block the cylinder wall thickness would be too thin after boring.

Joined:
Oct 19, 2006
Messages:
4,529
4
Location:
Maryland

17. 6.2Blazer1/2 ton status

Joined:
Feb 24, 2000
Messages:
4,649
8
Location:
Ohio
First of all, it's 0.040" overbore, or "40-thousands" of an inch not 0.40" (almost 1/2 inch).

A .040" overbore motor will make the same power as a .030" overbore motor, an .060" overbore motor, or a one with no overbore, assuming everything else is equal.....any power difference between them is more likely because of a difference in tolerances of other components. Doing an overbore on an engine is not a performance modification, it's simply done to clean up the cylinders from years of wear and tear when you rebuild it. It's kind of like turning down a brake rotor, you do it because it gives you a nice smooth surface again not because it makes it work better than a new un-turned rotor.

Sorry for the slight rant, but this is just one of my pet-peeves.

18. jt5121/2 ton statusPremium MemberGMOTM Winner

Joined:
Oct 19, 2006
Messages:
4,529
4
Location:
Maryland
rant away man, i hear you . I used to run a motorcycle shop and it would drive me nuts when people would come in asking about how much it would cost to put a "powerband" in their bike. Generally it was people that owned older 4-strokes and had just ridden a 2-stroke for the first time. trying to explain exactly what a "powerband " was and the difference between a 2-stroke and a 4 was enough to drive you nuts!

oh, i think the correct answer to "what is a 0.40 over 350?" ........scrap!

19. 4xcrazy3/4 ton status

Joined:
Oct 31, 2003
Messages:
9,458
2
Location:
Olympia/Lacey, Washington
got any of those "powerbands" for my .030 overbored 350?

Joined:
Dec 14, 2001
Messages:
21,986