I'm getting my rebuild for my 305 asap but there is a back log of 2 months for TWR pistons!! However, I have found a place that has a set 040 over.

What I want to know is, can I bore the block out that much and most importantly, can I run a supercharger with it? The reason I'm asking is that someone said the walls may be too thin and I'm planning on a D1sc next year at 12-15psig.

Thanks for the help.

Rob

 

I always thought that you could bore any block up to .60 over. But I could be wrong.

------------------
"Rice burners are like tampons...Every pu$$y has to have one"
'86 IROC
T-TOPS, TINTED WINDOWS, BRAKE LIGHT BLACKOUTS
GM GOODWRENCH 350
EDELBROCK TES HEADERS
3" Hooker CatBack w/Aero Chamber muffler
EDELBROCK 600CFM CARB.
KN AIRFILTER
ACCEL HEI DISTRIBUTOR
160* Stat, just switched to 180* b/c of winter coming and going to college in the mts.
3:73 Posi
Rebuilt 700R4
B&M Megashifter, 5" Autometer Tach w/shift lite

 

Nearly all of them will safely go to .040". You'll probably be OK.

------------------
"So many Mustangs, so little time..."
ICON Motorsports

 

BUY A 350! Don't be stupid with your money
www.sdpc2000.com
Longblock
10067353 $1300 (two piece rear, flat tappet)

12513151 $1500 (one piece roller)
http://www.sdpc2000.com/cart.asp?act...id=128&pid=105
it actually costs less to rebuild a 350 than a 305.

------------------
355 c.i.
Dart 180 Heads
Lunati 224/224 cam
Harland Sharp 1.5 rockers
Performer RPM Manifold
Holley 600 cfm double pumper
Hooker Super Competition Headers
Flowmaster Exhaust
Competition Engineering Sub-frame connectors
Super T-10
GM posi 3.42 rear
Hurst Roll Control
13.9@102

 

ok i'm getting a little tired of hearing about buy a 350... if people want to rebuild there 305's let them! theres nothing wrong with a 305 and i just had my shortblock rebuilt for 600 bucks, sure SOME 350 parts are cheaper, but it's all the same damn thing, besides who wants to be like everyone else? seeing as how most people ditched there 305's, i personally like my 305 and people tell me that it must be a 350.

 

AMEN!!!

------------------
1987 Black 305 TPI 5spd IROC, seems to be fully loaded, but can't find RPO codes.

AIM: IROC 5spd
http://www.geocities.com/chevy5spdiroc/87Roc.htm

 

THATS A BIG NEGATIVE ON THAT 0.40

THOSE ENGINES ONLY GO 0.30 MAX.

ANY MORE AND YOUR GONNA HAVE PROBLEMS.

PAL

 

Only reason a 305 wont go .040 is if there was core shift when the block was cast, the walls are plenty thick enough to handle .040.

That said, dont bore it .040 because you cant find pistons. Find a different manufacturer or supplier that has the right size ones in stock, there is no need to overbore more than you absolutely have to mainly because if there is a problem (I have seen it happen too) then you are screwed.

 

i agree dont go .40 over, i just had mine done .20 over that way if it needs it again i can go .30

 

if you couldn't bore it that much then there wouldn't be pistons for it in every catalog. Most people start with .030 so they can do another .030 in the future = .060

------------------

-Tas
'89 Formula WS-6

305, TBI, 700R4, P.A.W. 14x3 open element with K&N, Milodon 160* thermo, functional Formula hood, cross-flow Flowmaster, '99z28 rear pipes and tips, Hooker 1-5/8" 50 state legal headers, Dynomax 3" I pipe (PN 44063 and 43248)
Super GRK_Taz World
F-Body Dual Exaust
EFI & Intake Options
AOL IM: superGRtaz

Got Beach?

 

First off, there will be no problem going 40 over.
Second off, they dont sell 70 over pistons for 350's because they cant take it.
Third off, if there is a problem, the machine shop should know about it and tell you.
Fourth off, Dont go that big just because of the pistons, you'll regret it later when you cant go any bigger on the next rebuild.

------------------
You have walked onto the biggest baddest dog porch and you will be dealt with accordingly.

I'd rather be historically accurate than politically correct!

 

Absolutley nowhere can get me 305 pistons 30 over!!! It's F@#king unbelievable!!! I can't use my car!!

 

www.partsamerica.com

Sealed Power forged .030 over p/n L2487F-30, $59.99 each (dished - flat tops don't seem to be available .030 over).

Sealed Power hypereutectic .030 over p/n H534P-30, flat-top, $20.99 each.

If you want to SC, then the forged dished might be the way to go. If staying NA, then the hypereutectics.

------------------
82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R4. 2.93 limited slip. 2-1/2" cat-back, ZZ3 intake, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 CC system w/'87 LB9 block, ZZ3 cam, ported World 305 heads, Hooker 2055 headers, 3" Catco cat & 3" catback, restalled TC, Spohn SFCs).
57 Bel Air, my 1st car. '66 396, 9.7 CR forged TRWs, Weiand Action+, Holley 750VS w/4150 conversion, GK 270 cam, Magnum rockers, Jacobs Omnipack, 1-3/4" Hedders & 3" Warlocks, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, MegaShifter, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Idles smooth @ 600 RPM in D. Best 15.02/95.06 @ 5800' Bandimere (corrected 13.93/102.4 @ sea level).

 

http://www.enginekits.com/ They have .030 over pistons here, and pretty reasonable rebuild kits including a 335 stroker kit. My Dad owns a machine shop and does all of the rebuilding and machining for every dealer and garage in a 50 mile radius. 305s and 350s can both be bored .010, .020, .030, .040, and even .060 over with no problems. You can run a supercharger at 9.5:1 compression, and I wouldn't go any higher than that on compression regardless of how much you bore it to avoid heat problems. The only 305 I've ever seen overheat due to boring was one Dad bored .260 over. The only reason we even tried this was to see if a 305 could be turned into a 350. We didn't get into any water jackets at .260 over, and we ran the motor at 210 degrees with no overheating but couldn't get it any cooler running 8.5:1. I don't suggest boring any more than you have to, buy the pistons you need. Boring doesn't get you much power, and really isn't worth the trouble unless you need to get the cylinder reshaped.